WO2017047311A1

WO2017047311A1 - Photoelectric transducer and production method for same

Info

Publication number: WO2017047311A1
Application number: PCT/JP2016/073872
Authority: WO
Inventors: 雄太松本; 親扶岡本; 潤斉藤
Original assignee: シャープ株式会社
Priority date: 2015-09-18
Filing date: 2016-08-16
Publication date: 2017-03-23

Abstract

A photoelectric transducer (1) comprises: a first non-crystalline semiconductor layer (17) that is of a first conductivity type, and is provided upon a second surface (11b) of a semiconductor substrate (11); and a first non-crystalline semiconductor region (16) that is of a second conductivity type different from the first conductivity type, and is provided upon the second surface (11b). The first non-crystalline semiconductor layer (17) includes a first impurity that is of the first conductivity type. The first non-crystalline semiconductor region (16) includes the first impurity and a second impurity that is of the second conductivity type. The first non-crystalline semiconductor layer (17) and the first non-crystalline semiconductor region (16) constitute a single continuous and extending layer. As a result, the photoelectric transducer (1) has improved characteristics and reliability.

Description

Photoelectric conversion element and manufacturing method thereof

This application claims the benefit of priority to Japanese Patent Application Nos. 2015-185468 and 2015-185470 filed on Sep. 18, 2015. Include all of the content in this document.

One embodiment of the present invention relates to a photoelectric conversion element and a method for manufacturing the photoelectric conversion element.

A photoelectric conversion element that converts light energy such as sunlight into electrical energy is known (for example, see Patent Document 1). Patent Document 1 describes a method for manufacturing a photoelectric conversion element including a step of patterning a p-type amorphous semiconductor layer and an n-type amorphous semiconductor layer formed on a substrate by etching.

JP 2012-28718 A

However, a part of the surface of the substrate is exposed by etching the n-type amorphous semiconductor layer formed on the substrate. Contaminants may adhere to the exposed substrate surface. In addition, the surface of the substrate may be roughened by the etching of the n-type amorphous semiconductor layer. Therefore, there has been a problem that the characteristics and reliability of the photoelectric conversion element deteriorate.

One embodiment of the present invention has been made in view of the above problems, and an object thereof is to provide a photoelectric conversion element having improved characteristics and reliability and a method for manufacturing the photoelectric conversion element.

The photoelectric conversion element according to the first aspect of the present invention is provided on a semiconductor substrate having a first surface and a second surface opposite to the first surface, and on the second surface. A first amorphous semiconductor layer having a conductivity type; and a first amorphous semiconductor region provided on the second surface and having a second conductivity type different from the first conductivity type. The first amorphous semiconductor layer includes a first impurity having a first conductivity type. The first amorphous semiconductor region includes a first impurity and a second impurity having a second conductivity type. The first amorphous semiconductor layer and the first amorphous semiconductor region constitute one layer that extends continuously.

A photoelectric conversion element according to a second aspect of the present invention includes a semiconductor substrate having a first surface and a second surface opposite to the first surface, and a tunnel dielectric layer provided on the second surface A first amorphous semiconductor layer having a first conductivity type, and a second conductivity different from the first conductivity type, provided on the tunnel dielectric layer. And a first amorphous semiconductor region having a mold. The first amorphous semiconductor layer includes a first impurity having a first conductivity type. The first amorphous semiconductor region includes a first impurity and a second impurity having a second conductivity type. The first amorphous semiconductor layer and the first amorphous semiconductor region constitute one layer that extends continuously.

In the method for manufacturing a photoelectric conversion element according to the third aspect of the present invention, a first conductive material is formed on a second surface of a semiconductor substrate having a first surface and a second surface opposite to the first surface. Forming a first amorphous semiconductor layer having a mold. The first amorphous semiconductor layer includes a first impurity having a first conductivity type. The method for manufacturing a photoelectric conversion element according to the third aspect of the present invention further includes forming a first amorphous semiconductor region having the second conductivity type in the first amorphous semiconductor layer. The formation of the first amorphous semiconductor region in the first amorphous semiconductor layer means that a part of the first amorphous semiconductor layer has a second conductivity type different from the first conductivity type. Doping with a second impurity.

According to a fourth aspect of the present invention, there is provided a method for manufacturing a photoelectric conversion element comprising: forming a tunnel dielectric layer on a second surface of a semiconductor substrate having a first surface and a second surface opposite to the first surface. Forming a first amorphous semiconductor layer having a first conductivity type on the tunnel dielectric layer. The first amorphous semiconductor layer includes a first impurity having a first conductivity type. The method for manufacturing a photoelectric conversion element according to the fourth aspect of the present invention further includes forming a first amorphous semiconductor region having the second conductivity type in the first amorphous semiconductor layer. The formation of the first amorphous semiconductor region in the first amorphous semiconductor layer means that a part of the first amorphous semiconductor layer has a second conductivity type different from the first conductivity type. Doping with a second impurity.

According to the photoelectric conversion element of the first and second aspects of the present invention, a photoelectric conversion element having improved characteristics and reliability can be provided.

According to the method for manufacturing a photoelectric conversion element of the third and fourth aspects of the present invention, it is possible to provide a method for manufacturing a photoelectric conversion element having improved characteristics and reliability.

7 is a schematic plan view of a photoelectric conversion element according to Embodiments 1 to 7. FIG. FIG. 2 is a schematic cross-sectional view of the photoelectric conversion element according to Embodiments 1 to 3 along a cross-sectional line II-II shown in FIG. It is a schematic sectional drawing which shows 1 process in the manufacturing method of the photoelectric conversion element which concerns on Embodiment 1 to Embodiment 6 and Embodiment 8 to Embodiment 13. FIG. FIG. 7 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 3 in the method for manufacturing the photoelectric conversion element according to Embodiment 1 to Embodiment 6 and Embodiment 8 to Embodiment 13. FIG. 5 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 4 in the method for manufacturing the photoelectric conversion element according to Embodiment 1 to Embodiment 6. FIG. 6 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 5 in the method for manufacturing the photoelectric conversion element according to Embodiment 1 to Embodiment 6. It is a schematic sectional drawing which shows the next process of the process shown in FIG. 6 in the manufacturing method of the photoelectric conversion element which concerns on Embodiment 1 to Embodiment 6. FIG. FIG. 8 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 7 in the method for manufacturing the photoelectric conversion element according to Embodiment 1 to Embodiment 6. FIG. 9 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 8 in the method for manufacturing the photoelectric conversion element according to Embodiment 1. FIG. 9 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 8 in the method for manufacturing the photoelectric conversion element according to Embodiment 2 and Embodiment 5. FIG. 11 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 10 in the method for manufacturing a photoelectric conversion element according to Embodiment 2. FIG. 9 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 8 in the method for manufacturing the photoelectric conversion element according to Embodiment 3 and Embodiment 6. FIG. 13 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 12 in the method for manufacturing the photoelectric conversion element according to Embodiment 3. FIG. 7 is a schematic cross-sectional view of the photoelectric conversion element according to any of Embodiments 4 to 6 along a cross-sectional line XIV-XIV shown in FIG. FIG. 9 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 8 in the method for manufacturing a photoelectric conversion element according to Embodiment 4. FIG. 11 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 10 in the method for manufacturing the photoelectric conversion element according to Embodiment 5. FIG. 13 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 12 in the method for manufacturing the photoelectric conversion element according to Embodiment 6. FIG. 8 is a schematic cross-sectional view of the photoelectric conversion element according to Embodiment 7 taken along a cross-sectional line XVIII-XVIII shown in FIG. It is a schematic plan view of the photoelectric conversion element according to Embodiments 8 to 14. FIG. 20 is a schematic cross-sectional view of the photoelectric conversion element according to any of Embodiments 8 to 10 along a cross-sectional line XX-XX shown in FIG. It is a schematic sectional drawing which shows the next process of the process shown in FIG. 4 in the manufacturing method of the photoelectric conversion element which concerns on Embodiment 8 to Embodiment 13. FIG. FIG. 22 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 21 in the method for manufacturing the photoelectric conversion element according to the eighth to thirteenth embodiments. FIG. 23 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 22 in the method for manufacturing the photoelectric conversion element according to the eighth to thirteenth embodiments. FIG. 24 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 23 in the method for manufacturing the photoelectric conversion element according to the eighth to thirteenth embodiments. It is a schematic sectional drawing which shows the next process of the process shown in FIG. 24 in the manufacturing method of the photoelectric conversion element which concerns on Embodiment 8 to Embodiment 13. FIG. FIG. 26 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 25 in the method for manufacturing a photoelectric conversion element according to Embodiment 8. It is a schematic sectional drawing which shows the next process of the process shown in FIG. 25 in the manufacturing method of the photoelectric conversion element which concerns on Embodiment 9 and Embodiment 12. FIG. FIG. 28 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 27 in the method for manufacturing the photoelectric conversion element according to Embodiment 9. It is a schematic sectional drawing which shows the next process of the process shown in FIG. 25 in the manufacturing method of the photoelectric conversion element which concerns on Embodiment 10 and Embodiment 13. FIG. FIG. 30 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 29 in the method for manufacturing the photoelectric conversion element according to Embodiment 10. FIG. 20 is a schematic cross sectional view of the photoelectric conversion element according to any of the eleventh to thirteenth embodiments, taken along a sectional line XXXI-XXXI shown in FIG. FIG. 26 is a schematic sectional view showing a step subsequent to the step shown in FIG. 25 in the method for manufacturing the photoelectric conversion element according to the eleventh embodiment. FIG. 28 is a schematic sectional view showing a step subsequent to the step shown in FIG. 27 in the method for manufacturing a photoelectric conversion element according to the twelfth embodiment. FIG. 30 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 29 in the method for manufacturing the photoelectric conversion element according to Embodiment 13. FIG. 20 is a schematic cross sectional view of the photoelectric conversion element according to Embodiment 14 taken along a cross sectional line XXXV-XXXV shown in FIG.

Hereinafter, embodiments of the present invention will be described. The same components are denoted by the same reference numerals, and description thereof will not be repeated.

(Embodiment 1)
With reference to FIG.1 and FIG.2, the photoelectric conversion element 1 which concerns on Embodiment 1 is demonstrated. The photoelectric conversion element 1 of the present embodiment includes a semiconductor substrate 11, a first amorphous semiconductor layer 17, a first amorphous semiconductor region 16, a first electrode 19, and a second electrode 18. And mainly.

The semiconductor substrate 11 may be an n-type or p-type semiconductor substrate. In the present embodiment, an n-type single crystal silicon substrate is used as the semiconductor substrate 11. The semiconductor substrate 11 has a first surface 11a and a second surface 11b opposite to the first surface 11a. The first surface 11a of the semiconductor substrate 11 may be a light incident surface. The first surface 11a and the second surface 11b of the semiconductor substrate 11 have a first direction (for example, x direction) and a second direction (for example, y direction) that intersects the first direction (for example, x direction). Direction). The thickness direction of the semiconductor substrate 11 is a third direction (for example, z direction) that intersects the first direction (for example, x direction) and the second direction (for example, y direction).

The photoelectric conversion element 1 according to the present embodiment may include a second amorphous semiconductor layer 15 having i-type on the second surface 11 b of the semiconductor substrate 11. An i-type is formed between the first amorphous semiconductor layer 17 and the second surface 11b of the semiconductor substrate 11 and between the first amorphous semiconductor region 16 and the second surface 11b of the semiconductor substrate 11. A second amorphous semiconductor layer 15 may be provided. Specifically, the second amorphous semiconductor layer 15 may be in contact with the second surface 11 b of the semiconductor substrate 11. In the present embodiment, an i-type amorphous silicon film is used as the second amorphous semiconductor layer 15. In the second amorphous semiconductor layer 15 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the second surface 11 b of the semiconductor substrate 11. Recombination can be suppressed. The i-type second amorphous semiconductor layer 15 can improve the passivation characteristics of the photoelectric conversion element 1.

In this specification, “amorphous semiconductor” means not only an amorphous semiconductor in which dangling bonds of atoms constituting the semiconductor are not terminated with hydrogen, but also hydrogenated amorphous silicon and the like. Also included is an amorphous semiconductor in which dangling bonds of atoms constituting the semiconductor are terminated with hydrogen. In this specification, “i-type semiconductor” is not only a completely intrinsic semiconductor but also a sufficiently low concentration (the n-type impurity concentration is less than 1 × 10 ¹⁵ / cm ³ and the p-type impurity concentration is 1 × 10 Also included is a semiconductor mixed with n-type or p-type impurities of less than ¹⁵ / cm ³ .

The photoelectric conversion element 1 of the present embodiment includes the first amorphous semiconductor layer 17 having the first conductivity type on the second surface 11b of the semiconductor substrate 11. Specifically, the first amorphous semiconductor layer 17 having the first conductivity type may be provided on the surface of the second amorphous semiconductor layer 15 opposite to the semiconductor substrate 11. The first amorphous semiconductor layer 17 includes a first impurity having the first conductivity type. The first amorphous semiconductor layer 17 may be a p-type or n-type amorphous semiconductor layer. The first impurity may be a p-type impurity such as boron or an n-type impurity such as phosphorus. In the present embodiment, the first impurity is a p-type impurity such as boron, and the first amorphous semiconductor layer 17 is a p-type amorphous silicon film.

The photoelectric conversion element 1 according to the present embodiment is provided in the first amorphous semiconductor layer 17 and includes a first amorphous semiconductor region 16 having a second conductivity type different from the first conductivity type. Prepare. The photoelectric conversion element 1 of the present embodiment is provided on the second surface 11b of the semiconductor substrate 11 and includes a first amorphous semiconductor region 16 having a second conductivity type different from the first conductivity type. Prepare. The first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 constitute one layer that extends continuously. The surfaces of the first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 on the side opposite to the semiconductor substrate 11 may constitute one surface extending continuously.

The first amorphous semiconductor region 16 includes a first impurity having a first conductivity type and a second impurity having a second conductivity type different from the first conductivity type. The first amorphous semiconductor region 16 contains the second impurity having the second conductivity type more than the first impurity having the first conductivity type. Region 16 as a whole has the second conductivity type. The first amorphous semiconductor region 16 may be an n-type or p-type amorphous semiconductor region. The second impurity may be an n-type impurity such as phosphorus or a p-type impurity such as boron. In the present embodiment, the second impurity is an n-type impurity such as phosphorus, and the first amorphous semiconductor region 16 is an n-type amorphous silicon region. The first amorphous semiconductor region 16 may be provided in a stripe shape extending in the second direction (for example, the y direction).

The concentration of the first impurity in the first amorphous semiconductor region 16 is the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged, that is, the first May be constant in the direction (for example, the x direction). In this specification, the concentration of the first impurity in the first amorphous semiconductor region 16 is such that the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged. Is constant in the first amorphous semiconductor region 16 in the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged. It means that the variation in the concentration of the impurity is within 30% of the average concentration of the first impurity in the first amorphous semiconductor region 16 in this direction.

The concentration of the first impurity in the first amorphous semiconductor region 16 may be substantially the same as the concentration of the first impurity in the first amorphous semiconductor layer 17. In the present specification, the concentration of the first impurity in the first amorphous semiconductor region 16 is substantially the same as the concentration of the first impurity in the first amorphous semiconductor layer 17. The difference between the average concentration of the first impurity in one amorphous semiconductor region 16 and the average concentration of the first impurity in the first amorphous semiconductor layer 17 is the first concentration in the first amorphous semiconductor layer 17. It is within 20% of the average concentration of one impurity.

The concentration of the second impurity in the first amorphous semiconductor region 16 is the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged, that is, the first May be constant in the direction (for example, the x direction). In this specification, the concentration of the second impurity in the first amorphous semiconductor region 16 is such that the first amorphous semiconductor region 16 and the first amorphous semiconductor layer 17 are alternately arranged. Is constant in the second amorphous silicon region 16 in the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged. The variation in the impurity concentration is within 30% of the average concentration of the second impurity in the first amorphous semiconductor region 16 in this direction.

The photoelectric conversion element 1 of the present embodiment includes a first electrode 19 that is electrically connected to the first amorphous semiconductor layer 17. The first electrode 19 may be provided on the second surface 11 b of the semiconductor substrate 11. More specifically, the first electrode 19 may be provided on the first amorphous semiconductor layer 17. The first electrode 19 may be provided in a stripe shape extending in the second direction (for example, the y direction). A metal electrode may be exemplified as the first electrode 19. In the present embodiment, silver (Ag) is used as the first electrode 19. In the present embodiment, the first electrode 19 may be a p-type electrode.

The photoelectric conversion element 1 of this embodiment includes a second electrode 18 that is electrically connected to the first amorphous semiconductor region 16. The second electrode 18 may be provided on the second surface 11 b of the semiconductor substrate 11. More specifically, the second electrode 18 may be provided on the first amorphous semiconductor region 16. The second electrode 18 may be provided in a stripe shape extending in the second direction (for example, the y direction). A metal electrode may be exemplified as the second electrode 18. In the present embodiment, silver (Ag) is used as the second electrode 18. In the present embodiment, the second electrode 18 may be an n-type electrode.

In the photoelectric conversion element 1 of the present embodiment, the semiconductor substrate 11 and the first amorphous semiconductor layer 17 are heterojunction through the second amorphous semiconductor layer 15, and the semiconductor substrate 11 and the first amorphous semiconductor layer 17 are connected. The amorphous semiconductor region 16 is heterojunction with the second amorphous semiconductor layer 15. Therefore, the photoelectric conversion element 1 has improved passivation characteristics and a high open circuit voltage V _OC . According to the photoelectric conversion element 1 of the present embodiment, the efficiency of converting light energy into electrical energy can be improved.

In the photoelectric conversion element 1 of the present embodiment, the first surface 11a of the semiconductor substrate 11 may include an uneven structure. Light enters the photoelectric conversion element 1 from the first surface 11a side. By providing the concavo-convex structure on the first surface 11a of the semiconductor substrate 11 that is the light incident surface, reflection of incident light on the first surface 11a of the semiconductor substrate 11 can be suppressed, and more Light can enter the photoelectric conversion element 1. The efficiency of converting light energy into electric energy in the photoelectric conversion element 1 can be improved.

The photoelectric conversion element 1 of the present embodiment may include an i-type third amorphous semiconductor layer 12 on the first surface 11 a of the semiconductor substrate 11. By providing the i-type third amorphous semiconductor layer 12 on the first surface 11 a of the semiconductor substrate 11, the passivation characteristics on the first surface 11 a of the semiconductor substrate 11 can be improved.

The photoelectric conversion element 1 of the present embodiment may include a fourth amorphous semiconductor layer 13 having the same conductivity type as the semiconductor substrate 11 on the first surface 11 a of the semiconductor substrate 11. Specifically, a fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 may be provided on the third amorphous semiconductor layer 12 having i type. The fourth amorphous semiconductor layer 13 can be an n-type or p-type amorphous semiconductor layer. In the present embodiment, an n-type amorphous silicon film is used as the fourth amorphous semiconductor layer 13.

The fourth amorphous semiconductor layer 13 having the same conductivity type as the semiconductor substrate 11 may function as a surface electric field layer. When light enters the photoelectric conversion element 1, carriers are generated in the semiconductor substrate 11. The fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 generates an electric field in the vicinity of the first surface 11a of the semiconductor substrate 11, and an energy band is generated in the vicinity of the first surface 11a of the semiconductor substrate 11. Curve. Carriers approaching the first surface 11 a of the semiconductor substrate 11 are pushed back into the semiconductor substrate 11 by the electric field and the curvature of the energy band. Therefore, recombination of carriers on the first surface 11a of the semiconductor substrate 11 can be suppressed.

A dielectric layer 14 may be provided on the first surface 11 a of the semiconductor substrate 11. The dielectric layer 14 may be composed of a single layer or a plurality of layers. Examples of the material of the dielectric layer 14 include silicon nitride (SiN _x ) and silicon oxide (SiO _x ). The dielectric layer 14 may function as an antireflection film. The dielectric layer 14 may function as a passivation film.

An example of a method for manufacturing the photoelectric conversion element 1 of the present embodiment will be described below with reference to FIGS.

Referring to FIG. 3, a semiconductor substrate 11 having a first surface 11a and a second surface 11b opposite to the first surface 11a is prepared. With reference to FIG. 4, an uneven structure may be formed on first surface 11 a of semiconductor substrate 11. For example, the first surface 11a of the semiconductor substrate 11 which is an n-type single crystal silicon substrate is anisotropically etched using potassium hydroxide (KOH), whereby the first surface 11a of the semiconductor substrate 11 is uneven. A structure may be formed.

Referring to FIG. 5, i-type third amorphous semiconductor layer 12 may be formed on first surface 11 a of semiconductor substrate 11. A fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 may be formed on the first surface 11 a of the semiconductor substrate 11. Specifically, a fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 may be formed on the i-type third amorphous semiconductor layer 12. A method for forming the third amorphous semiconductor layer 12 and the fourth amorphous semiconductor layer 13 is not particularly limited, and may be, for example, a plasma chemical vapor deposition (CVD) method.

Referring to FIG. 6, dielectric layer 14 may be formed on first surface 11 a of semiconductor substrate 11. Specifically, the dielectric layer 14 may be formed on the fourth amorphous semiconductor layer 13 having the same conductivity type as the semiconductor substrate 11. The formation method of the dielectric layer 14 is not particularly limited, but may be, for example, a plasma chemical vapor deposition (CVD) method.

Referring to FIG. 7, an i-type second amorphous semiconductor layer 15 may be formed on the second surface 11 b of the semiconductor substrate 11. Referring to FIG. 8, first amorphous semiconductor layer 17 having the first conductivity type is formed on second surface 11 b of semiconductor substrate 11. Specifically, the first amorphous semiconductor layer 17 having the first conductivity type is formed on the second amorphous semiconductor layer 15 having the i type. The first amorphous semiconductor layer 17 includes a first impurity having the first conductivity type. A method for forming the second amorphous semiconductor layer 15 and the first amorphous semiconductor layer 17 is not particularly limited, and may be, for example, a plasma chemical vapor deposition (CVD) method.

Referring to FIG. 9, the first amorphous semiconductor region 16 having the second conductivity type is formed in the first amorphous semiconductor layer 17. The formation of the first amorphous semiconductor region 16 in the first amorphous semiconductor layer 17 means that a second portion different from the first conductivity type is formed in a part of the first amorphous semiconductor layer 17. Doping with a second impurity having a conductivity type. The first amorphous semiconductor region 16 includes a first impurity having a first conductivity type and a second impurity having a second conductivity type different from the first conductivity type. The first amorphous semiconductor region 16 contains the second impurity having the second conductivity type more than the first impurity having the first conductivity type. Region 16 as a whole has the second conductivity type.

The concentration of the first impurity in the first amorphous semiconductor region 16 is constant in the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged. Also good. The concentration of the first impurity in the first amorphous semiconductor region 16 may be substantially the same as the concentration of the first impurity in the first amorphous semiconductor layer 17. The first amorphous semiconductor region 16 may exist over the entire thickness of the first amorphous semiconductor layer 17.

Doping the second impurity in part of the first amorphous semiconductor layer 17 may include ion implantation of the second impurity in part of the first amorphous semiconductor layer 17. That is, the second impurity may be doped into part of the first amorphous semiconductor layer 17 by ion implantation. Specifically, by irradiating a part of the first amorphous semiconductor layer 17 with the ion beam 21 of the second impurity, the second impurity is applied to a part of the first amorphous semiconductor layer 17. It may be doped. Thus, the first amorphous semiconductor region 16 having the second conductivity type may be formed in the first amorphous semiconductor layer 17.

In order to prevent the second impurity from being doped in the other part of the first amorphous semiconductor layer 17 when the second impurity is doped in a part of the first amorphous semiconductor layer 17, A mask 22 having an opening corresponding to a part of the first amorphous semiconductor layer 17 and covering the other part of the first amorphous semiconductor layer 17 may be used.

After a part of the first amorphous semiconductor layer 17 is doped with the second impurity, the first impurity contained in the first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 are added to the first amorphous semiconductor layer 17. In order to activate the second impurity contained, the first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 may be annealed. Then, a first electrode 19 that is electrically connected to the first amorphous semiconductor layer 17 is formed on the second surface 11 b of the semiconductor substrate 11. Specifically, the first electrode 19 is formed on the first amorphous semiconductor layer 17. A second electrode 18 that is electrically connected to the first amorphous semiconductor region 16 is formed on the second surface 11 b of the semiconductor substrate 11. Specifically, the second electrode 18 is formed on the first amorphous semiconductor region 16. Thus, the photoelectric conversion element 1 of the present embodiment shown in FIGS. 1 and 2 can be manufactured.

The effect of the photoelectric conversion element 1 of this Embodiment and its manufacturing method is demonstrated.
The photoelectric conversion element 1 of the present embodiment is provided on a semiconductor substrate 11 having a first surface 11a and a second surface 11b opposite to the first surface 11a, and the second surface 11b, A first amorphous semiconductor layer 17 having a first conductivity type and a first amorphous semiconductor having a second conductivity type different from the first conductivity type, provided on the second surface 11b Region 16. The first amorphous semiconductor layer 17 includes a first impurity having the first conductivity type. The first amorphous semiconductor region 16 includes a first impurity and a second impurity having a second conductivity type. The first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 constitute one layer that extends continuously.

A structure that can be manufactured without exposing the second surface 11b of the semiconductor substrate 11 after the first amorphous semiconductor layer 17 is formed on the second surface 11b of the semiconductor substrate 11 is described in this embodiment. The photoelectric conversion element 1 is provided. A structure that can be manufactured without contamination of the second surface 11b of the semiconductor substrate 11 or roughening of the second surface 11b of the semiconductor substrate 11 due to etching of the amorphous semiconductor layer is described in this embodiment. The photoelectric conversion element 1 is provided. The photoelectric conversion element 1 of the present embodiment has improved characteristics and reliability.

In the photoelectric conversion element 1 of the present embodiment, the first amorphous semiconductor region 16 may exist over the entire thickness of the first amorphous semiconductor layer 17. The distance between the first amorphous semiconductor region 16 and the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the second conductivity type of the first amorphous semiconductor region 16 are the first. A single amorphous semiconductor region 16 can be collected with higher efficiency. According to the photoelectric conversion element 1 of the present embodiment, the efficiency of converting light energy into electrical energy can be improved.

In the photoelectric conversion element 1 of the present embodiment, the concentration of the first impurity in the first amorphous semiconductor region 16 is such that the first amorphous semiconductor region 16 and the first amorphous semiconductor layer 17 are the same. It may be constant in the alternately arranged directions. After the first amorphous semiconductor layer 17 is formed on the second surface 11b of the semiconductor substrate 11, a structure that can be manufactured without exposing the second surface 11b of the semiconductor substrate 11 is formed in the photoelectric conversion element 1. Has. The photoelectric conversion element 1 of the present embodiment has improved characteristics and reliability.

In the photoelectric conversion element 1 of the present embodiment, the first amorphous semiconductor layer 17 and the second surface 11 b of the semiconductor substrate 11 and the first amorphous semiconductor region 16 and the second of the semiconductor substrate 11 are used. An i-type second amorphous semiconductor layer 15 may be further provided between the first surface 11b and the first surface 11b. In the second amorphous semiconductor layer 15 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the second surface 11 b of the semiconductor substrate 11. Recombination can be suppressed. According to the photoelectric conversion element 1 of the present embodiment, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

The photoelectric conversion element 1 according to the present embodiment is provided on the second surface 11b of the semiconductor substrate 11, and the first electrode 19 electrically connected to the first amorphous semiconductor layer 17 and the semiconductor A second electrode 18 that is provided on the second surface 11 b of the substrate 11 and electrically connected to the first amorphous semiconductor region 16 may be further provided. In the photoelectric conversion element 1 of the present embodiment, the first electrode 19 and the second electrode 18 are not provided on the first surface 11a side of the semiconductor substrate 11 which is a light incident surface. Light incident on the photoelectric conversion element 1 is not blocked by the first electrode 19 and the second electrode 18. According to the photoelectric conversion element 1 of the present embodiment, a high short-circuit current J _SC can be obtained, and the efficiency of converting light energy into electric energy can be improved.

The photoelectric conversion element 1 of the present embodiment may further include a dielectric layer 14 on the first surface 11a of the semiconductor substrate 11. When the dielectric layer 14 functions as an antireflection film, the dielectric layer 14 can cause more light to enter the photoelectric conversion element 1. According to the photoelectric conversion element 1 of the present embodiment, the efficiency of converting light energy into electrical energy can be improved. When the dielectric layer 14 functions as a passivation film, the carrier generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 is the first dielectric layer 14 of the semiconductor substrate 11. It is possible to suppress recombination on the surface 11a. According to the photoelectric conversion element 1 of the present embodiment, the efficiency of converting light energy into electrical energy can be improved.

The photoelectric conversion element 1 of the present embodiment may further include a third amorphous semiconductor layer 12 having i-type on the first surface 11 a of the semiconductor substrate 11. In the third amorphous semiconductor layer 12 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the first surface 11 a of the semiconductor substrate 11. Recombination can be suppressed. According to the photoelectric conversion element 1 of the present embodiment, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

The photoelectric conversion element 1 of the present embodiment may further include a fourth amorphous semiconductor layer 13 having the same conductivity type as the semiconductor substrate 11 on the first surface 11 a of the semiconductor substrate 11. The fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 has the first surface 11 a of the semiconductor substrate 11 among the carriers generated in the semiconductor substrate 11 when light enters the photoelectric conversion element 1. The carrier approaching can be pushed back into the semiconductor substrate 11. The fourth amorphous semiconductor layer 13 can suppress recombination of this carrier on the first surface 11 a of the semiconductor substrate 11. According to the photoelectric conversion element 1 of the present embodiment, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

In the photoelectric conversion element 1 of the present embodiment, the first surface 11a of the semiconductor substrate 11 may include an uneven structure. By providing the concavo-convex structure on the first surface 11 a of the semiconductor substrate 11 that is the light incident surface, more light can be incident into the photoelectric conversion element 1. According to the photoelectric conversion element 1 of the present embodiment, the efficiency of converting light energy into electrical energy can be improved.

The manufacturing method of the photoelectric conversion element 1 according to the present embodiment includes the first surface 11a and the second surface 11b of the semiconductor substrate 11 having the second surface 11b opposite to the first surface 11a. Forming a first amorphous semiconductor layer 17 having one conductivity type. The first amorphous semiconductor layer 17 includes a first impurity having the first conductivity type. The method for manufacturing the photoelectric conversion element 1 according to the present embodiment further includes forming the first amorphous semiconductor region 16 having the second conductivity type in the first amorphous semiconductor layer 17. The formation of the first amorphous semiconductor region 16 in the first amorphous semiconductor layer 17 means that a second portion different from the first conductivity type is formed in a part of the first amorphous semiconductor layer 17. Doping with a second impurity having a conductivity type.

After the first amorphous semiconductor layer 17 is formed on the second surface 11b of the semiconductor substrate 11, the photoelectric conversion element 1 can be manufactured without exposing the second surface 11b of the semiconductor substrate 11. The photoelectric conversion element 1 can be manufactured without the contaminants adhering to the second surface 11b of the semiconductor substrate 11 or the second surface 11b of the semiconductor substrate 11 being roughened by etching of the amorphous semiconductor layer. According to the method for manufacturing the photoelectric conversion element 1 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

In the method for manufacturing the photoelectric conversion element 1 of the present embodiment, the first amorphous semiconductor region 16 may exist over the entire thickness of the first amorphous semiconductor layer 17. The distance between the first amorphous semiconductor region 16 and the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the second conductivity type of the first amorphous semiconductor region 16 are the first. A single amorphous semiconductor region 16 can be collected with higher efficiency. According to the manufacturing method of the photoelectric conversion element 1 of the present embodiment, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

In the method for manufacturing the photoelectric conversion element 1 of the present embodiment, the concentration of the first impurity in the first amorphous semiconductor region 16 is the same as that of the first amorphous semiconductor region 16 and the first amorphous semiconductor layer. It may be constant in a direction in which 17 and 17 are alternately arranged. After the first amorphous semiconductor layer 17 is formed on the second surface 11b of the semiconductor substrate 11, the photoelectric conversion element 1 can be manufactured without exposing the second surface 11b of the semiconductor substrate 11. According to the method for manufacturing the photoelectric conversion element 1 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

In the method for manufacturing the photoelectric conversion element 1 according to the present embodiment, the first amorphous semiconductor layer 17 is formed on the second surface 11 b of the semiconductor substrate 11 before the first amorphous semiconductor layer 17 is formed on the second surface 11 b of the semiconductor substrate 11. In addition, an i-type second amorphous semiconductor layer 15 may be further formed. In the second amorphous semiconductor layer 15 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the second surface 11 b of the semiconductor substrate 11. Recombination can be suppressed. According to the manufacturing method of the photoelectric conversion element 1 of this Embodiment, the photoelectric conversion element with which the passivation characteristic and the efficiency which converts light energy into electrical energy were improved can be manufactured.

In the method for manufacturing the photoelectric conversion element 1 of the present embodiment, doping a second impurity into a part of the first amorphous semiconductor layer 17 causes a part of the first amorphous semiconductor layer 17 to be doped. Ion implantation of the second impurity may be included. According to the method for manufacturing the photoelectric conversion element 1 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

In the method for manufacturing the photoelectric conversion element 1 according to the present embodiment, the first electrode 19 that is electrically connected to the first amorphous semiconductor layer 17 is formed on the second surface 11 b of the semiconductor substrate 11. And forming a second electrode 18 electrically connected to the first amorphous semiconductor region 16 on the second surface 11 b of the semiconductor substrate 11. According to the method of manufacturing the photoelectric conversion element 1 of the present embodiment, the first electrode 19 and the second electrode 18 are photoelectric elements that are not provided on the first surface 11a side of the semiconductor substrate 11 that is the light incident surface. The conversion element 1 can be manufactured. Light incident on the photoelectric conversion element 1 is not blocked by the first electrode 19 and the second electrode 18. According to the method for manufacturing the photoelectric conversion element 1 of the present embodiment, a photoelectric conversion element having a high short-circuit current J _SC and improved efficiency in converting light energy into electric energy can be manufactured.

The method for manufacturing the photoelectric conversion element 1 according to the present embodiment may further include forming the dielectric layer 14 on the first surface 11 a of the semiconductor substrate 11. When the dielectric layer 14 functions as an antireflection film, the dielectric layer 14 can cause more light to enter the photoelectric conversion element 1. According to the manufacturing method of the photoelectric conversion element 1 of the present embodiment, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured. When the dielectric layer 14 functions as a passivation film, the carrier generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 is the first dielectric layer 14 of the semiconductor substrate 11. It is possible to suppress recombination on the surface 11a. According to the manufacturing method of the photoelectric conversion element 1 of the present embodiment, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

The method for manufacturing the photoelectric conversion element 1 of the present embodiment may further include forming the third amorphous semiconductor layer 12 having i-type on the first surface 11 a of the semiconductor substrate 11. In the third amorphous semiconductor layer 12 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the first surface 11 a of the semiconductor substrate 11. Recombination can be suppressed. According to the manufacturing method of the photoelectric conversion element 1 of this Embodiment, the photoelectric conversion element with which the passivation characteristic and the efficiency which converts light energy into electrical energy were improved can be manufactured.

The manufacturing method of the photoelectric conversion element 1 according to the present embodiment further includes forming the fourth amorphous semiconductor layer 13 having the same conductivity type as the semiconductor substrate 11 on the first surface 11 a of the semiconductor substrate 11. You may prepare. The fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 has the first surface 11 a of the semiconductor substrate 11 among the carriers generated in the semiconductor substrate 11 when light enters the photoelectric conversion element 1. The carrier approaching can be pushed back into the semiconductor substrate 11. The fourth amorphous semiconductor layer 13 can suppress recombination of this carrier on the first surface 11 a of the semiconductor substrate 11. According to the manufacturing method of the photoelectric conversion element 1 of this Embodiment, the photoelectric conversion element with which the passivation characteristic and the efficiency which converts light energy into electrical energy were improved can be manufactured.

The method for manufacturing the photoelectric conversion element 1 according to the present embodiment may further include forming a concavo-convex structure on the first surface 11 a of the semiconductor substrate 11. By forming a concavo-convex structure on the first surface 11 a of the semiconductor substrate 11, which is the light incident surface, more light can be incident into the photoelectric conversion element 1. According to the manufacturing method of the photoelectric conversion element 1 of the present embodiment, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

(Embodiment 2)
With reference to FIG. 1 to FIG. 8, FIG. 10, and FIG. The photoelectric conversion element 1 of the present embodiment has a configuration similar to that of the photoelectric conversion element 1 of the first embodiment. Although the manufacturing method of the photoelectric conversion element 1 of this Embodiment is fundamentally equipped with the process similar to the manufacturing method of the photoelectric conversion element 1 of Embodiment 1, it differs in the following points.

In the method for manufacturing the photoelectric conversion element 1 according to the first embodiment, the second impurity is doped in part of the first amorphous semiconductor layer 17 by the ion implantation method. On the other hand, in the method for manufacturing the photoelectric conversion element 1 of the present embodiment, doping the second impurity into a part of the first amorphous semiconductor layer 17 means that the first amorphous semiconductor layer 17 is doped. Forming the dopant-containing film 26 containing the second impurity thereon, and transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17. Good. More specifically, the formation of the dopant-containing film 26 containing the second impurity on the first amorphous semiconductor layer 17 means that the second amorphous semiconductor layer 17 is formed on the second amorphous semiconductor layer 17. A doping paste containing impurities may be applied. Transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 may include heat-treating the doping paste.

An example of a method for manufacturing the photoelectric conversion element 1 according to the present embodiment will be described below with reference to FIGS.

3 to 8, the third amorphous semiconductor layer 12, the fourth amorphous semiconductor layer 13, and the dielectric layer 14 are formed on the first surface 11 a of the semiconductor substrate 11. The second amorphous semiconductor layer 15 and the first amorphous semiconductor layer 17 having the first conductivity type are formed on the second surface 11 b of the semiconductor substrate 11.

Referring to FIG. 10, a dopant-containing film 26 containing a second impurity having the second conductivity type is formed on a part of the first amorphous semiconductor layer 17. Examples of the dopant-containing film 26 include a doping paste containing a second impurity having n type such as phosphorus and a doping paste containing a second impurity having p type such as boron. The doping paste including the second impurity having n-type may include a phosphorus compound, a silicon oxide precursor, a solvent, and a thickener. The doping paste containing the second impurity having p-type may include a boron compound, a silicon oxide precursor, a solvent, and a thickener. In the present embodiment, as the dopant-containing film 26, a doping paste containing an n-type second impurity such as phosphorus may be used. The doping paste may be applied on a part of the first amorphous semiconductor layer 17 by inkjet, screen printing, or the like.

Referring to FIG. 11, the dopant-containing film 26 is heat-treated so that the second impurity contained in the dopant-containing film 26 is transferred to a part of the first amorphous semiconductor layer 17. In the present embodiment, for example, the dopant-containing film 26 that is a doping paste is heat-treated at a temperature of 100 ° C. or more and 250 ° C. or less, and the second impurity contained in the dopant-containing film 26 that is a doping paste A part of the crystalline semiconductor layer 17 is doped. Thus, the first amorphous semiconductor region 16 having the second conductivity type can be formed in the first amorphous semiconductor layer 17 having the first conductivity type. The dopant-containing film 26 may be heat-treated using a heating furnace, or the dopant-containing film 26 may be heat-treated by irradiating the dopant-containing film 26 with laser light.

When the dopant-containing film 26 is heat-treated, the first impurity in the first amorphous semiconductor layer 17 and the second impurity in the first amorphous semiconductor region 16 can be activated. In order to further activate the first impurity in the first amorphous semiconductor layer 17 and the second impurity in the first amorphous semiconductor region 16, the first amorphous semiconductor layer 17 and the first impurity One amorphous semiconductor region 16 may be further annealed.

Then, the remaining dopant-containing film 26 is removed using a mixed solution of sulfuric acid and hydrogen peroxide solution, a mixed solution of hydrochloric acid and hydrogen peroxide solution, or hydrofluoric acid. Subsequently, the first electrode 19 and the second electrode 18 are formed on the second surface 11 b of the semiconductor substrate 11. Thus, the photoelectric conversion element 1 of the present embodiment shown in FIGS. 1 and 2 can be manufactured.

The manufacturing method of the photoelectric conversion element 1 of the present embodiment has the same effect as the manufacturing method of the photoelectric conversion element 1 of the first embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 1 according to the present embodiment, doping the second impurity into a part of the first amorphous semiconductor layer 17 may cause the part of the first amorphous semiconductor layer 17 to be doped. Forming a dopant-containing film 26 containing a second impurity at the same time, and transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17. . According to the method for manufacturing the photoelectric conversion element 1 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

In the method for manufacturing the photoelectric conversion element 1 of the present embodiment, the formation of the dopant-containing film 26 containing the second impurity on the first amorphous semiconductor layer 17 is the first amorphous semiconductor layer 17. A doping paste containing the second impurity may be applied on a part of the substrate. Transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 may include heat-treating the doping paste. That is, in the method for manufacturing the photoelectric conversion element 1 according to the present embodiment, doping the second impurity into a part of the first amorphous semiconductor layer 17 is a part of the first amorphous semiconductor layer 17. Applying a doping paste containing a second impurity on the part and heat-treating the doping paste may be included.

By using a doping paste as the dopant-containing film 26, the first amorphous semiconductor region 16 can be formed in the first amorphous semiconductor layer 17 with high pattern accuracy. By using a doping paste as the dopant-containing film 26, the dopant-containing film 26 can be formed on the first amorphous semiconductor layer 17 by inkjet, screen printing, or the like. According to the manufacturing method of the photoelectric conversion element 1 of this Embodiment, the photoelectric conversion element which has the improved characteristic and reliability can be manufactured at a cheap and simple process.

(Embodiment 3)
With reference to FIG. 1 to FIG. 8, FIG. 12, and FIG. The photoelectric conversion element 1 of the present embodiment has a configuration similar to that of the photoelectric conversion element 1 of the first embodiment. Although the manufacturing method of the photoelectric conversion element 1 of this Embodiment is fundamentally equipped with the process similar to the manufacturing method of the photoelectric conversion element 1 of Embodiment 1, it differs in the following points.

In the method for manufacturing the photoelectric conversion element 1 according to the first embodiment, the second impurity is doped in part of the first amorphous semiconductor layer 17 by the ion implantation method. On the other hand, in the method for manufacturing the photoelectric conversion element 1 of the present embodiment, doping the second impurity into a part of the first amorphous semiconductor layer 17 means that the first amorphous semiconductor layer 17 is doped. Forming the dopant-containing film 26 containing the second impurity thereon, and transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17. Good. More specifically, transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 irradiates a part of the dopant-containing film 26 with the laser beam 27. You may include that. That is, the second impurity may be doped into a part of the first amorphous semiconductor layer 17 by a laser doping method.

3 to 8, the third amorphous semiconductor layer 12, the fourth amorphous semiconductor layer 13, and the dielectric layer 14 are formed on the first surface 11 a of the semiconductor substrate 11. The second amorphous semiconductor layer 15 and the first amorphous semiconductor layer 17 are formed on the second surface 11 b of the semiconductor substrate 11.

Referring to FIG. 12, a dopant-containing film 26 containing a second impurity having the second conductivity type is formed on the first amorphous semiconductor layer 17. Examples of the dopant-containing film 26 may include phosphorus silicate glass (PSG), boron silicate glass (BSG), and polyboron film (PBF). In the present embodiment, phosphorus silicate glass (PSG) is used as the dopant-containing film 26.

Referring to FIG. 13, a part of the dopant-containing film 26 is irradiated with laser light 27 to transfer the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17. . In the present embodiment, a part of the dopant-containing film 26 is locally heated by irradiating a part of the dopant-containing film 26 with the laser light 27. Of the first amorphous semiconductor layer 17, only the region corresponding to the portion irradiated with the laser light 27 is doped with the second impurity contained in the dopant-containing film 26. Thus, the first amorphous semiconductor region 16 having the second conductivity type can be formed in the first amorphous semiconductor layer 17 having the first conductivity type.

By irradiating a part of the dopant-containing film 26 with the laser beam 27, a part of the dopant-containing film 26 and a part of the first amorphous semiconductor layer 17 are locally heated. When a part of the dopant-containing film 26 is irradiated with the laser beam 27, the second impurity in the first amorphous semiconductor region 16 can be activated.

Then, the remaining dopant-containing film 26 is removed using a mixed solution of sulfuric acid and hydrogen peroxide solution, a mixed solution of hydrochloric acid and hydrogen peroxide solution, or hydrofluoric acid. In order to further activate the first impurity in the first amorphous semiconductor layer 17 and the second impurity in the first amorphous semiconductor region 16, the first amorphous semiconductor layer 17 and The first amorphous semiconductor region 16 may be further annealed. Subsequently, the first electrode 19 and the second electrode 18 are formed on the second surface 11 b of the semiconductor substrate 11. Thus, the photoelectric conversion element 1 of the present embodiment shown in FIGS. 1 and 2 can be manufactured.

In the method for manufacturing the photoelectric conversion element 1 according to the present embodiment, shifting the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 is one of the dopant-containing films 26. Irradiation of the laser beam 27 to the part may be included. That is, the second impurity may be doped into a part of the first amorphous semiconductor layer 17 by a laser doping method. The laser doping method can diffuse the dopant in a shorter time than the method of diffusing the dopant using a heating furnace. According to the manufacturing method of the photoelectric conversion element 1 of this Embodiment, the photoelectric conversion element which has the improved characteristic and reliability can be manufactured at a cheap and simple process.

(Embodiment 4)
With reference to FIG.1 and FIG.14, the photoelectric conversion element 2 of Embodiment 4 is demonstrated. The photoelectric conversion element 2 of the present embodiment is basically the same as the photoelectric conversion element 1 of the first embodiment, but differs in the following points.

The photoelectric conversion element 2 according to the present embodiment is provided in the second amorphous semiconductor layer 15 and further includes a second amorphous semiconductor region 46 having the second conductivity type. The second amorphous semiconductor layer 15 and the second amorphous semiconductor region 46 are provided on the second surface 11 b of the semiconductor substrate 11. The second amorphous semiconductor layer 15 and the second amorphous semiconductor region 46 constitute one layer extending continuously. The second amorphous semiconductor region 46 includes a second impurity having the second conductivity type. The second amorphous semiconductor region 46 is in contact with the first amorphous semiconductor region 16. The second amorphous semiconductor region 46 may exist over the entire thickness of the second amorphous semiconductor layer 15. The second amorphous semiconductor region 46 may or may not be in contact with the second surface 11b of the semiconductor substrate 11.

In the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged, that is, in the first direction (for example, the x direction), the second amorphous semiconductor region 46 may have substantially the same width as the first amorphous semiconductor region 16. In the present specification, the second amorphous semiconductor region 46 has substantially the same width as the first amorphous semiconductor region 16 because the first amorphous semiconductor region 16 and the first amorphous semiconductor region 16 The difference between the width of the second amorphous semiconductor region 46 and the width of the first amorphous semiconductor region 16 in the direction in which the porous semiconductor layers 17 are alternately arranged is the first amorphous semiconductor layer 17 in this direction. It means that it is within 20% of the width of the semiconductor region 16. The width of the first amorphous semiconductor region 16 is such that the first direction of the region having the second impurity concentration of 80% or more of the average concentration of the second impurity in the first amorphous semiconductor region 16 is set. It is defined by the length in (for example, x direction). The width of the second amorphous semiconductor region 46 is the first direction of the region having the second impurity concentration of 80% or more of the average concentration of the second impurity in the second amorphous semiconductor region 46. It is defined by the length in (for example, x direction).

The concentration of the second impurity in the second amorphous semiconductor region 46 is the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged, that is, the first May be constant in the direction (for example, the x direction). In this specification, the concentration of the second impurity in the second amorphous semiconductor region 46 is such that the first amorphous semiconductor region 16 and the first amorphous semiconductor layer 17 are alternately arranged. Is constant in the second amorphous semiconductor region 46 in the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged. The variation in the impurity concentration is within 30% of the average concentration of the second impurity in the second amorphous semiconductor region 46 in this direction.

The second amorphous semiconductor region 46 may have a second impurity concentration substantially the same as that of the first amorphous semiconductor region 16. In the present specification, the second amorphous semiconductor region 46 has the second impurity concentration substantially the same as that of the first amorphous semiconductor region 16. The difference between the average concentration of the second impurity and the average concentration of the second impurity in the first amorphous semiconductor region 16 is the average concentration of the second impurity in the first amorphous semiconductor region 16. It means within 30%.

A method for manufacturing the photoelectric conversion element 2 according to Embodiment 4 will be described with reference to FIGS. The manufacturing method of the photoelectric conversion element 2 of the present embodiment is basically the same as the manufacturing method of the photoelectric conversion element 1 of the first embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 2 according to the present embodiment, the second amorphous semiconductor layer 15 is doped with the second impurity, and the second amorphous semiconductor layer 15 is filled with the second impurity. An amorphous semiconductor region 46 may be further formed. The second amorphous semiconductor region 46 includes a second impurity having the second conductivity type. The second amorphous semiconductor region 46 is in contact with the first amorphous semiconductor region 16. Specifically, doping part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 with the second impurity may cause the first amorphous semiconductor layer 17 to be doped. The second impurity may be ion-implanted into part of the first amorphous semiconductor layer 15 and part of the second amorphous semiconductor layer 15.

Referring to FIG. 15, the first amorphous semiconductor region 16 is formed in the first amorphous semiconductor layer 17 and the second amorphous semiconductor layer 15 has the second conductivity type. The formation of the second amorphous semiconductor region 46 means that a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 have a second conductivity type. Doping with two impurities. In other words, by doping a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 with the second impurity having the second conductivity type, The first amorphous semiconductor region 16 is formed in the amorphous semiconductor layer 17, and the second amorphous semiconductor region 46 having the second conductivity type is formed in the second amorphous semiconductor layer 15. Is formed.

Specifically, doping part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 with the second impurity may cause the first amorphous semiconductor layer 17 to be doped. And second ion implantation of a second impurity into a part of the second amorphous semiconductor layer 15. That is, the second impurity may be doped into part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 by ion implantation. Specifically, by irradiating a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 with the ion beam 21 of the second impurity, the first non-crystalline semiconductor layer 17 is irradiated. A part of the crystalline semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 may be doped with the second impurity. Thus, in one step of irradiating the ion beam 21 of the second impurity, the second impurity is applied to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15. Can be doped.

When the second impurity is doped into a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15, another part of the first amorphous semiconductor layer 17 is changed. In order to prevent the second impurity and other portions of the second amorphous semiconductor layer 15 from being doped with the second impurity, an opening corresponding to a part of the first amorphous semiconductor layer 17 is provided. A mask 22 that covers other portions of one amorphous semiconductor layer 17 may be used.

The first amorphous semiconductor layer 17 includes a first impurity after the second amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 are doped with the second impurity. In order to activate the first impurity and the second impurity contained in the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46, the first amorphous semiconductor layer 17 and the first amorphous semiconductor layer 17 are activated. The amorphous semiconductor region 16 and the second amorphous semiconductor region 46 may be annealed.

Then, the first electrode 19 that is electrically connected to the first amorphous semiconductor layer 17 is formed on the second surface 11 b of the semiconductor substrate 11. Specifically, the first electrode 19 is formed on the first amorphous semiconductor layer 17. A second electrode 18 that is electrically connected to the first amorphous semiconductor region 16 is formed on the second surface 11 b of the semiconductor substrate 11. Specifically, the second electrode 18 is formed on the first amorphous semiconductor region 16. Thus, the photoelectric conversion element 2 of the present embodiment shown in FIGS. 1 and 14 can be manufactured.

The photoelectric conversion element 2 and its manufacturing method of the present embodiment have the same effects as the photoelectric conversion element 1 of the first embodiment and its manufacturing method, but are different in the following points.

The photoelectric conversion element 2 according to the present embodiment may be provided in the second amorphous semiconductor layer 15 and further include a second amorphous semiconductor region 46 having the second conductivity type. The second amorphous semiconductor region 46 may contain a second impurity having the second conductivity type. The second amorphous semiconductor region 46 may be in contact with the first amorphous semiconductor region 16. In the photoelectric conversion element 2 according to the present embodiment, the semiconductor substrate 11 includes an amorphous semiconductor region having the second conductivity type, which includes the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46, and the semiconductor substrate 11. The distance can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, the second amorphous semiconductor region 46 and the second amorphous semiconductor region 46 have the second. The carriers corresponding to the conductivity types of the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46 can be collected with higher efficiency. According to the photoelectric conversion element 2 of the present embodiment, the efficiency of converting light energy into electrical energy can be improved.

In the method for manufacturing the photoelectric conversion element 2 according to the present embodiment, the second amorphous semiconductor layer 15 is doped with the second impurity, and the second amorphous semiconductor layer 15 is filled with the second impurity. An amorphous semiconductor region 46 may be further formed. The second amorphous semiconductor region 46 may contain a second impurity having the second conductivity type. The second amorphous semiconductor region 46 may be in contact with the first amorphous semiconductor region 16. According to the method for manufacturing the photoelectric conversion element 2 of the present embodiment, the amorphous semiconductor region having the second conductivity type composed of the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46, and The distance from the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, the second amorphous semiconductor region 46 and the second amorphous semiconductor region 46 have the second. The carriers corresponding to the conductivity types of the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46 can be collected with higher efficiency. According to the manufacturing method of the photoelectric conversion element 2 of the present embodiment, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

In the method for manufacturing the photoelectric conversion element 2 according to the present embodiment, the second impurity is doped into a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15. Ion implantation of a second impurity into part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 may be included. In one step of irradiating the ion beam 21 of the second impurity, a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 are doped with the second impurity. obtain. According to the method for manufacturing the photoelectric conversion element 2 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(Embodiment 5)
With reference to FIG. 3 to FIG. 8, FIG. 10, FIG. 14, and FIG. The photoelectric conversion element 2 of the present embodiment has the same configuration as the photoelectric conversion element 2 of the fourth embodiment. The manufacturing method of the photoelectric conversion element 2 of the present embodiment basically includes the same steps as the manufacturing method of the photoelectric conversion element 2 of the fourth embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 2 of Embodiment 4, the second impurity is introduced into part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 by ion implantation. It was doped. On the other hand, in the manufacturing method of the photoelectric conversion element 2 according to the present embodiment, a part of the first amorphous semiconductor layer 17 and the first A part of the second amorphous semiconductor layer 15 is doped with the second impurity.

Specifically, a dopant-containing film 26 containing a second impurity is formed on the first amorphous semiconductor layer 17. Then, the second impurity contained in the dopant-containing film 26 is transferred to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15. More specifically, the formation of the dopant-containing film 26 containing the second impurity on the first amorphous semiconductor layer 17 means that the second amorphous semiconductor layer 17 is formed on the second amorphous semiconductor layer 17. A doping paste containing impurities may be applied. Transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 means that the doping paste is heat-treated. May be included.

An example of a method for manufacturing the photoelectric conversion element 2 of the present embodiment will be described below with reference to FIGS. 3 to 8, FIG. 10, and FIG.

3 to 8, the third amorphous semiconductor layer 12, the fourth amorphous semiconductor layer 13, and the dielectric layer 14 are formed on the first surface 11 a of the semiconductor substrate 11. The second amorphous semiconductor layer 15 and the first amorphous semiconductor layer 17 are formed on the second surface 11 b of the semiconductor substrate 11. Referring to FIG. 10, a dopant-containing film 26 containing a second impurity having the second conductivity type is formed on part of the first amorphous semiconductor layer 17. The dopant-containing film 26 may be a doping paste containing a second impurity having the second conductivity type.

Referring to FIG. 16, the dopant-containing film 26 is heat-treated so that the second impurity contained in the dopant-containing film 26 is part of the first amorphous semiconductor layer 17 and the second amorphous semiconductor layer 15. To some of them. In one step of heat-treating the dopant-containing film 26, a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 may be doped with the second impurity. The photoelectric conversion element of the present embodiment except that the second impurity is transferred to a part of the second amorphous semiconductor layer 15 in addition to a part of the first amorphous semiconductor layer 17. The manufacturing method 2 is the same as the manufacturing method of the photoelectric conversion element 1 of the second embodiment.

The manufacturing method of the photoelectric conversion element 2 of the present embodiment has the effect of the manufacturing method of the photoelectric conversion element 2 of the fourth embodiment and the effect of the manufacturing method of the photoelectric conversion element 1 of the second embodiment.

In the method of manufacturing the photoelectric conversion element 2 of the present embodiment, doping a second impurity into a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 Forming a dopant-containing film 26 containing a second impurity on the first amorphous semiconductor layer 17, and applying the second impurity contained in the dopant-containing film 26 to one of the first amorphous semiconductor layer 17 And transition to a part of the second amorphous semiconductor layer 15. In one step of transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15, A part of the crystalline semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 may be doped with the second impurity.

In the method for manufacturing the photoelectric conversion element 2 of the present embodiment, the formation of the dopant-containing film 26 containing the second impurity on the first amorphous semiconductor layer 17 is the first amorphous semiconductor layer 17. A doping paste containing the second impurity may be applied on a part of the substrate. Transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 means that the doping paste is heat-treated. May be included. In one step of heat-treating the dopant-containing film 26 (doping paste), a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 are doped with the second impurity. obtain. According to the method for manufacturing the photoelectric conversion element 2 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(Embodiment 6)
With reference to FIG. 3 to FIG. 8, FIG. 12, FIG. 14, and FIG. The photoelectric conversion element 2 of the present embodiment has the same configuration as the photoelectric conversion element 2 of the fourth embodiment. The manufacturing method of the photoelectric conversion element 2 of the present embodiment basically includes the same steps as the manufacturing method of the photoelectric conversion element 2 of the fourth embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 2 of Embodiment 4, the second impurity is introduced into part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 by ion implantation. It was doped. On the other hand, in the method for manufacturing the photoelectric conversion element 2 according to the present embodiment, as in the method for manufacturing the photoelectric conversion element 1 according to Embodiment 3, one of the first amorphous semiconductor layers 17 is formed by laser doping. The second impurity is doped into the portion and part of the second amorphous semiconductor layer 15.

Specifically, a dopant-containing film 26 containing a second impurity is formed on the first amorphous semiconductor layer 17. Then, by irradiating a part of the dopant-containing film 26 with the laser beam 27, a second impurity is introduced into a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15. It may be doped.

An example of a method for manufacturing the photoelectric conversion element 2 of the present embodiment will be described below with reference to FIGS. 3 to 8, 12, and 17.

Referring to FIG. 12, a dopant-containing film 26 containing a second impurity having the second conductivity type is formed on the first amorphous semiconductor layer 17. The dopant-containing film 26 may be a doping paste containing a second impurity having the second conductivity type. Referring to FIG. 17, a part of the dopant-containing film 26 is irradiated with a laser beam 27, and the second impurity contained in the dopant-containing film 26 is changed into a part of the first amorphous semiconductor layer 17 and the second impurity. To a part of the amorphous semiconductor layer 15. In one step of irradiating a part of the dopant-containing film 26 with the laser beam 27, a second impurity is added to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15. Can be doped. The photoelectric conversion element of the present embodiment except that the second impurity is transferred to a part of the second amorphous semiconductor layer 15 in addition to a part of the first amorphous semiconductor layer 17. The manufacturing method 2 is the same as the manufacturing method of the photoelectric conversion element 1 of the third embodiment.

The manufacturing method of the photoelectric conversion element 2 of the present embodiment has the effect of the manufacturing method of the photoelectric conversion element 2 of the fourth embodiment and the effect of the manufacturing method of the photoelectric conversion element 1 of the third embodiment. In the method for manufacturing the photoelectric conversion element 2 according to the present embodiment, the second impurity contained in the dopant-containing film 26 is part of the first amorphous semiconductor layer 17 and the second amorphous semiconductor layer 15. The transition to the portion may include irradiating a part of the dopant-containing film 26 with the laser beam 27. In one step of irradiating a part of the dopant-containing film 26 with the laser beam 27, a second impurity is added to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15. Can be doped. According to the method for manufacturing the photoelectric conversion element 2 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(Embodiment 7)
With reference to FIG. 18, the photoelectric conversion element 3 of Embodiment 7 is demonstrated. Although the photoelectric conversion element 3 of this Embodiment is equipped with the structure similar to the photoelectric conversion element 1 of Embodiment 1, it differs in the following points.

The photoelectric conversion element 3 of the present embodiment does not include the second amorphous semiconductor layer 15. The first amorphous semiconductor layer 17 is provided on the second surface 11 b of the semiconductor substrate 11 and is in direct contact with the second surface 11 b of the semiconductor substrate 11. The first amorphous semiconductor region 16 may be in direct contact with the second surface 11 b of the semiconductor substrate 11. The first amorphous semiconductor region 16 may exist over the entire thickness of the first amorphous semiconductor layer 17. The first amorphous semiconductor region 16 may or may not be in contact with the second surface 11b of the semiconductor substrate 11.

The manufacturing method of the photoelectric conversion element 3 of the present embodiment is the same as the manufacturing method of the photoelectric conversion element 1 of Embodiments 1 to 3, except that the second amorphous semiconductor layer 15 is formed. It is the same. Specifically, in the method of manufacturing the photoelectric conversion element 3 according to the present embodiment, forming the first amorphous semiconductor layer 17 on the second surface 11 b of the semiconductor substrate 11 Forming the first amorphous semiconductor layer 17 in direct contact with the second surface 11b.

The photoelectric conversion element 3 and the manufacturing method thereof according to the present embodiment have the same effects as the photoelectric conversion element 1 and the manufacturing method thereof according to the first to third embodiments, but are different in the following points.

In the photoelectric conversion element 3 of the present embodiment, the first amorphous semiconductor layer 17 may be in direct contact with the second surface 11b of the semiconductor substrate 11. Since the first amorphous semiconductor layer 17 is in direct contact with the second surface 11b of the semiconductor substrate 11, the distance between the first amorphous semiconductor layer 17 and the semiconductor substrate 11, and the first amorphous semiconductor The distance between the first amorphous semiconductor region 16 provided in the layer 17 and the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the first conductivity type of the first amorphous semiconductor layer 17 are first One amorphous semiconductor layer 17 can be collected with higher efficiency. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the second conductivity type of the first amorphous semiconductor region 16 are the first. A single amorphous semiconductor region 16 can be collected with higher efficiency. According to the photoelectric conversion element 3 of the present embodiment, the efficiency of converting light energy into electric energy can be improved.

In the method for manufacturing the photoelectric conversion element 3 according to the present embodiment, the formation of the first amorphous semiconductor layer 17 on the second surface 11 b of the semiconductor substrate 11 means that the second surface 11 b of the semiconductor substrate 11 is formed. It may also include forming the first amorphous semiconductor layer 17 in direct contact. Since the first amorphous semiconductor layer 17 is in direct contact with the second surface 11b of the semiconductor substrate 11, the distance between the first amorphous semiconductor layer 17 and the semiconductor substrate 11, and the first amorphous semiconductor The distance between the first amorphous semiconductor region 16 provided in the layer 17 and the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the first conductivity type of the first amorphous semiconductor layer 17 are first One amorphous semiconductor layer 17 can be collected with higher efficiency. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the second conductivity type of the first amorphous semiconductor region 16 are the first. A single amorphous semiconductor region 16 can be collected with higher efficiency. According to the manufacturing method of the photoelectric conversion element 3 of the present embodiment, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

(Embodiment 8)
With reference to FIG.19 and FIG.20, the photoelectric conversion element 5 which concerns on Embodiment 8 is demonstrated. The photoelectric conversion element 5 of the present embodiment includes a semiconductor substrate 11, a tunnel dielectric layer 20, a first amorphous semiconductor layer 17, a first amorphous semiconductor region 16, and a first electrode 19. And the second electrode 18 are mainly provided.

The semiconductor substrate 11 may be an n-type or p-type semiconductor substrate. In the present embodiment, an n-type single crystal silicon substrate is used as the semiconductor substrate 11. The semiconductor substrate 11 includes a first surface 11a, a second surface 11b opposite to the first surface 11a, a first side surface 11c connecting the first surface 11a and the second surface 11b, The first surface 11a and the second surface 11b are connected to each other, and the second side surface 11d is located opposite to the first side surface 11c. The first surface 11a of the semiconductor substrate 11 may be a light incident surface. The first surface 11a and the second surface 11b of the semiconductor substrate 11 have a first direction (for example, x direction) and a second direction (for example, y direction) that intersects the first direction (for example, x direction). Direction). The thickness direction of the semiconductor substrate 11 is a third direction (for example, z direction) that intersects the first direction (for example, x direction) and the second direction (for example, y direction).

The tunnel dielectric layer 20 is provided on at least the second surface 11 b of the semiconductor substrate 11. Specifically, the tunnel dielectric layer 20 may contact the second surface 11 b of the semiconductor substrate 11. The tunnel dielectric layer 20 is a dielectric layer having passivation characteristics such as a silicon oxide layer. The tunnel dielectric layer 20 suppresses recombination of carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 on the second surface 11 b of the semiconductor substrate 11. Can do. The tunnel dielectric layer 20 can improve the passivation characteristics of the photoelectric conversion element 5. The tunnel dielectric layer 20 uses carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 as the first amorphous semiconductor layer 17 and the first amorphous semiconductor. Tunnel to region 16. Therefore, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 can be efficiently collected.

The tunnel dielectric layer 20 may have a thickness of 0.2 nm to 5.0 nm, preferably 0.5 nm to 3.0 nm. The thickness of the tunnel dielectric layer 20 may be the length of the tunnel dielectric layer 20 in the third direction (eg, the z direction). The tunnel dielectric layer 20 having a thickness of 0.2 nm or more, preferably 0.5 nm or more can further improve the passivation characteristics of the photoelectric conversion element 5. The tunnel dielectric layer 20 having a thickness of 5.0 nm or less, preferably 3.0 nm or less, generates carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11. The tunnel can be more efficiently tunneled to the first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16. Carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 can be collected more efficiently.

The tunnel dielectric layer 20 may be further provided on the first surface 11 a of the semiconductor substrate 11. Therefore, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 can be suppressed from recombining on the first surface 11 a of the semiconductor substrate 11. The tunnel dielectric layer 20 may be further provided on the first side surface 11 c and the second side surface 11 d of the semiconductor substrate 11. Therefore, it is suppressed that the carriers generated in the semiconductor substrate 11 by the light incident from the first surface 11a side of the semiconductor substrate 11 are recombined on the first side surface 11c and the second side surface 11d of the semiconductor substrate 11. Can be done.

The photoelectric conversion element 5 of the present embodiment may include a second amorphous semiconductor layer 15 having i-type on the tunnel dielectric layer 20. A second amorphous semiconductor having i-type between the first amorphous semiconductor layer 17 and the tunnel dielectric layer 20 and between the first amorphous semiconductor region 16 and the tunnel dielectric layer 20. A layer 15 may be provided. Specifically, the second amorphous semiconductor layer 15 may be in contact with the tunnel dielectric layer 20. In the present embodiment, an i-type amorphous silicon film is used as the second amorphous semiconductor layer 15. In the second amorphous semiconductor layer 15 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the second surface 11 b of the semiconductor substrate 11. Recombination can be suppressed. The i-type second amorphous semiconductor layer 15 can improve the passivation characteristics of the photoelectric conversion element 5.

The photoelectric conversion element 5 of the present embodiment includes the first amorphous semiconductor layer 17 having the first conductivity type on the tunnel dielectric layer 20. Specifically, the first amorphous semiconductor layer 17 having the first conductivity type may be provided on the surface of the second amorphous semiconductor layer 15 opposite to the tunnel dielectric layer 20. . The first amorphous semiconductor layer 17 includes a first impurity having the first conductivity type. The first amorphous semiconductor layer 17 may be a p-type or n-type amorphous semiconductor layer. The first impurity may be a p-type impurity such as boron or an n-type impurity such as phosphorus. In the present embodiment, the first impurity is a p-type impurity such as boron, and the first amorphous semiconductor layer 17 is a p-type amorphous silicon film.

The photoelectric conversion element 5 of the present embodiment is provided in the first amorphous semiconductor layer 17 and includes a first amorphous semiconductor region 16 having a second conductivity type different from the first conductivity type. Prepare. The photoelectric conversion element 5 of the present embodiment is provided on the tunnel dielectric layer 20 and includes a first amorphous semiconductor region 16 having a second conductivity type different from the first conductivity type. The first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 constitute one layer that extends continuously. The surfaces of the first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 on the side opposite to the semiconductor substrate 11 may constitute one surface extending continuously.

The concentration of the first impurity in the first amorphous semiconductor region 16 is the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged, that is, the first May be constant in the direction (for example, the x direction). The concentration of the first impurity in the first amorphous semiconductor region 16 may be substantially the same as the concentration of the first impurity in the first amorphous semiconductor layer 17. The concentration of the second impurity in the first amorphous semiconductor region 16 is the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged, that is, the first May be constant in the direction (for example, the x direction).

The photoelectric conversion element 5 of the present embodiment includes a first electrode 19 that is electrically connected to the first amorphous semiconductor layer 17. The first electrode 19 may be provided on the second surface 11 b of the semiconductor substrate 11. More specifically, the first electrode 19 may be provided on the first amorphous semiconductor layer 17. The first electrode 19 may be provided in a stripe shape extending in the second direction (for example, the y direction). A metal electrode may be exemplified as the first electrode 19. In the present embodiment, silver (Ag) is used as the first electrode 19. In the present embodiment, the first electrode 19 may be a p-type electrode.

The photoelectric conversion element 5 of this embodiment includes a second electrode 18 that is electrically connected to the first amorphous semiconductor region 16. The second electrode 18 may be provided on the second surface 11 b of the semiconductor substrate 11. More specifically, the second electrode 18 may be provided on the first amorphous semiconductor region 16. The second electrode 18 may be provided in a stripe shape extending in the second direction (for example, the y direction). A metal electrode may be exemplified as the second electrode 18. In the present embodiment, silver (Ag) is used as the second electrode 18. In the present embodiment, the second electrode 18 may be an n-type electrode.

In the photoelectric conversion element 5 of the present embodiment, the semiconductor substrate 11 and the first amorphous semiconductor layer 17 are heterojunctioned via the second amorphous semiconductor layer 15 and the tunnel dielectric layer 20, and the semiconductor The substrate 11 and the first amorphous semiconductor region 16 are heterojunctioned via the second amorphous semiconductor layer 15 and the tunnel dielectric layer 20. Therefore, the photoelectric conversion element 5 having improved passivation characteristics and a high open circuit voltage V _OC can be obtained. In the photoelectric conversion element 5, the efficiency of converting light energy into electrical energy can be improved.

In the photoelectric conversion element 5 of the present embodiment, the first surface 11a of the semiconductor substrate 11 may include an uneven structure. Light enters the photoelectric conversion element 5 from the first surface 11a side. By providing the concavo-convex structure on the first surface 11a of the semiconductor substrate 11 that is the light incident surface, reflection of incident light on the first surface 11a of the semiconductor substrate 11 can be suppressed, and more Light can enter the photoelectric conversion element 5. The efficiency of converting light energy into electrical energy in the photoelectric conversion element 5 can be improved.

The photoelectric conversion element 5 of the present embodiment may include an i-type third amorphous semiconductor layer 12 on the first surface 11 a of the semiconductor substrate 11. By providing the i-type third amorphous semiconductor layer 12 on the first surface 11 a of the semiconductor substrate 11, the passivation characteristics on the first surface 11 a of the semiconductor substrate 11 can be improved.

The photoelectric conversion element 5 of the present embodiment may include a fourth amorphous semiconductor layer 13 having the same conductivity type as the semiconductor substrate 11 on the first surface 11a of the semiconductor substrate 11. Specifically, a fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 may be provided on the third amorphous semiconductor layer 12 having i type. The fourth amorphous semiconductor layer 13 can be an n-type or p-type amorphous semiconductor layer. In the present embodiment, an n-type amorphous silicon film is used as the fourth amorphous semiconductor layer 13. The fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 may function as a surface electric field layer. When light enters the photoelectric conversion element 5, carriers are generated in the semiconductor substrate 11. The fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 generates an electric field in the vicinity of the first surface 11a of the semiconductor substrate 11, and an energy band is generated in the vicinity of the first surface 11a of the semiconductor substrate 11. Curve. Carriers approaching the first surface 11 a of the semiconductor substrate 11 are pushed back into the semiconductor substrate 11 by the electric field and the curvature of the energy band. In the first surface 11a of the semiconductor substrate 11, recombination of carriers can be suppressed.

An example of a method for manufacturing the photoelectric conversion element 5 of the present embodiment will be described below with reference to FIGS. 3, 4, and 21 to 26.

Referring to FIG. 21, tunnel dielectric layer 20 is formed on second surface 11 b of semiconductor substrate 11. The tunnel dielectric layer 20 may be further formed on the first surface 11 a of the semiconductor substrate 11. The tunnel dielectric layer 20 may be further formed on the first side surface 11 c and the second side surface 11 d of the semiconductor substrate 11. In the present embodiment, tunnel dielectric layer 20 is formed on the entire surface of semiconductor substrate 11.

The tunnel dielectric layer 20 may be formed on at least the second surface 11b of the semiconductor substrate 11 by immersing at least the second surface 11b of the semiconductor substrate 11 in ozone water or hydrogen peroxide solution. The tunnel dielectric layer 20 may be formed on at least the second surface 11 b of the semiconductor substrate 11 by thermally oxidizing at least the second surface 11 b of the semiconductor substrate 11. The tunnel dielectric layer 20 may be formed on at least the second surface 11 b of the semiconductor substrate 11 by depositing the tunnel dielectric layer 20 on at least the second surface 11 b of the semiconductor substrate 11.

Referring to FIG. 22, i-type third amorphous semiconductor layer 12 may be formed on first surface 11 a of semiconductor substrate 11. A fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 may be formed on the first surface 11 a of the semiconductor substrate 11. Specifically, a fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 may be formed on the i-type third amorphous semiconductor layer 12. A method for forming the third amorphous semiconductor layer 12 and the fourth amorphous semiconductor layer 13 is not particularly limited, and may be, for example, a plasma chemical vapor deposition (CVD) method.

Referring to FIG. 23, dielectric layer 14 may be formed on first surface 11a of semiconductor substrate 11. Specifically, the dielectric layer 14 may be formed on the fourth amorphous semiconductor layer 13 having the same conductivity type as the semiconductor substrate 11. The formation method of the dielectric layer 14 is not particularly limited, but may be, for example, a plasma chemical vapor deposition (CVD) method.

Referring to FIG. 24, second amorphous semiconductor layer 15 having i-type may be formed on tunnel dielectric layer 20. Referring to FIG. 25, first amorphous semiconductor layer 17 having the first conductivity type is formed on tunnel dielectric layer 20. Specifically, the first amorphous semiconductor layer 17 having the first conductivity type is formed on the second amorphous semiconductor layer 15 having the i type. The first amorphous semiconductor layer 17 includes a first impurity having the first conductivity type. A method for forming the second amorphous semiconductor layer 15 and the first amorphous semiconductor layer 17 is not particularly limited, and may be, for example, a plasma chemical vapor deposition (CVD) method.

Referring to FIG. 26, the first amorphous semiconductor region 16 having the second conductivity type is formed in the first amorphous semiconductor layer 17. The formation of the first amorphous semiconductor region 16 in the first amorphous semiconductor layer 17 means that a second portion different from the first conductivity type is formed in a part of the first amorphous semiconductor layer 17. Doping with a second impurity having a conductivity type. The first amorphous semiconductor region 16 includes a first impurity having a first conductivity type and a second impurity having a second conductivity type different from the first conductivity type. The first amorphous semiconductor region 16 contains the second impurity having the second conductivity type more than the first impurity having the first conductivity type. Region 16 as a whole has the second conductivity type.

After a part of the first amorphous semiconductor layer 17 is doped with the second impurity, the first impurity contained in the first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 are added to the first amorphous semiconductor layer 17. In order to activate the second impurity contained, the first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 may be annealed. Then, a first electrode 19 that is electrically connected to the first amorphous semiconductor layer 17 is formed on the second surface 11 b of the semiconductor substrate 11. Specifically, the first electrode 19 is formed on the first amorphous semiconductor layer 17. A second electrode 18 that is electrically connected to the first amorphous semiconductor region 16 is formed on the second surface 11 b of the semiconductor substrate 11. Specifically, the second electrode 18 is formed on the first amorphous semiconductor region 16. In this way, the photoelectric conversion element 5 of the present embodiment shown in FIGS. 19 and 20 can be manufactured.

The effect of the photoelectric conversion element 5 of this Embodiment and its manufacturing method is demonstrated.
The photoelectric conversion element 5 of this embodiment includes a semiconductor substrate 11 having a first surface 11a and a second surface 11b opposite to the first surface 11a, and a tunnel provided on the second surface 11b. A dielectric layer 20 is provided on the tunnel dielectric layer 20, and is provided on the first amorphous semiconductor layer 17 having the first conductivity type, the tunnel dielectric layer 20, and the first conductive layer. And a first amorphous semiconductor region 16 having a second conductivity type different from the type. The first amorphous semiconductor layer 17 includes a first impurity having the first conductivity type. The first amorphous semiconductor region 16 includes a first impurity and a second impurity having a second conductivity type. The first amorphous semiconductor layer 17 and the first amorphous semiconductor region 16 constitute one layer that extends continuously.

The tunnel dielectric layer 20 suppresses recombination of carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 on the second surface 11 b of the semiconductor substrate 11. Can do. The photoelectric conversion element 5 of the present embodiment has improved passivation characteristics.

The tunnel dielectric layer 20 uses carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 as the first amorphous semiconductor layer 17 and the first amorphous semiconductor. Tunnel to region 16. According to the photoelectric conversion element 5 of the present embodiment, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 can be efficiently collected.

In the photoelectric conversion element 5 of the present embodiment, after the tunnel dielectric layer 20 and the first amorphous semiconductor layer 17 are formed on the second surface 11 b of the semiconductor substrate 11, the second of the semiconductor substrate 11 is formed. It has a structure that can be manufactured without exposing the surface 11b. A structure that can be manufactured without contamination of the second surface 11b of the semiconductor substrate 11 or roughening of the second surface 11b of the semiconductor substrate 11 due to etching of the amorphous semiconductor layer is described in this embodiment. The photoelectric conversion element 5 is provided. The photoelectric conversion element 5 of the present embodiment has improved characteristics and reliability.

In the photoelectric conversion element 5 of the present embodiment, the first amorphous semiconductor region 16 may exist over the entire thickness of the first amorphous semiconductor layer 17. The distance between the first amorphous semiconductor region 16 and the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the second conductivity type of the first amorphous semiconductor region 16 are the first. A single amorphous semiconductor region 16 can be collected with higher efficiency. According to the photoelectric conversion element 5 of the present embodiment, the efficiency of converting light energy into electric energy can be improved.

In the photoelectric conversion element 5 of the present embodiment, the concentration of the first impurity in the first amorphous semiconductor region 16 is such that the first amorphous semiconductor region 16 and the first amorphous semiconductor layer 17 are the same. It may be constant in the alternately arranged directions. A structure that can be manufactured without exposing the second surface 11b of the semiconductor substrate 11 after the tunnel dielectric layer 20 and the first amorphous semiconductor layer 17 are formed on the second surface 11b of the semiconductor substrate 11. Is provided with the photoelectric conversion element 5. The photoelectric conversion element 5 of the present embodiment has improved characteristics and reliability.

In the photoelectric conversion element 5 of the present embodiment, between the first amorphous semiconductor layer 17 and the tunnel dielectric layer 20 and between the first amorphous semiconductor region 16 and the tunnel dielectric layer 20, An i-type second amorphous semiconductor layer 15 may be further provided. In the second amorphous semiconductor layer 15 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the second surface 11 b of the semiconductor substrate 11. Recombination can be suppressed. According to the photoelectric conversion element 5 of the present embodiment, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

In the photoelectric conversion element 5 of the present embodiment, the tunnel dielectric layer 20 may have a thickness of 0.2 nm to 5.0 nm. The tunnel dielectric layer 20 having a thickness of 0.2 nm or more can further improve the passivation characteristics of the photoelectric conversion element 5. The tunnel dielectric layer 20 having a thickness of 5.0 nm or less is configured to cause carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 to be generated in the first amorphous semiconductor layer. 17 and the first amorphous semiconductor region 16 can be more efficiently tunneled. According to the photoelectric conversion element 5 of the present embodiment, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 can be collected more efficiently.

The photoelectric conversion element 5 according to the present embodiment is provided on the second surface 11b of the semiconductor substrate 11, and the first electrode 19 electrically connected to the first amorphous semiconductor layer 17 and the semiconductor A second electrode 18 that is provided on the second surface 11 b of the substrate 11 and electrically connected to the first amorphous semiconductor region 16 may be further provided. In the photoelectric conversion element 5 of the present embodiment, the first electrode 19 and the second electrode 18 are not provided on the first surface 11a side of the semiconductor substrate 11 which is a light incident surface. Light incident on the photoelectric conversion element 5 is not blocked by the first electrode 19 and the second electrode 18. According to the photoelectric conversion element 5 of the present embodiment, a high short-circuit current J _SC can be obtained, and the efficiency of converting light energy into electrical energy can be improved.

The photoelectric conversion element 5 of the present embodiment may further include a dielectric layer 14 on the first surface 11a of the semiconductor substrate 11. When the dielectric layer 14 functions as an antireflection film, the dielectric layer 14 can cause more light to enter the photoelectric conversion element 5. According to the photoelectric conversion element 5 of the present embodiment, the efficiency of converting light energy into electric energy can be improved. When the dielectric layer 14 functions as a passivation film, the carrier generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 is the first dielectric layer 14 of the semiconductor substrate 11. It is possible to suppress recombination on the surface 11a. According to the photoelectric conversion element 5 of the present embodiment, the efficiency of converting light energy into electric energy can be improved.

The photoelectric conversion element 5 according to the present embodiment may further include an i-type third amorphous semiconductor layer 12 on the first surface 11 a of the semiconductor substrate 11. In the third amorphous semiconductor layer 12 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the first surface 11 a of the semiconductor substrate 11. Recombination can be suppressed. According to the photoelectric conversion element 5 of the present embodiment, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

The photoelectric conversion element 5 of the present embodiment may further include a fourth amorphous semiconductor layer 13 having the same conductivity type as the semiconductor substrate 11 on the first surface 11 a of the semiconductor substrate 11. The fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 has the first surface 11 a of the semiconductor substrate 11 among the carriers generated in the semiconductor substrate 11 when light enters the photoelectric conversion element 5. The carrier approaching can be pushed back into the semiconductor substrate 11. The fourth amorphous semiconductor layer 13 can suppress recombination of this carrier on the first surface 11 a of the semiconductor substrate 11. According to the photoelectric conversion element 5 of the present embodiment, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

In the photoelectric conversion element 5 of the present embodiment, the first surface 11a of the semiconductor substrate 11 may include an uneven structure. By providing a concavo-convex structure on the first surface 11 a of the semiconductor substrate 11, which is the light incident surface, more light can be incident into the photoelectric conversion element 5. According to the photoelectric conversion element 5 of the present embodiment, the efficiency of converting light energy into electric energy can be improved.

In the method of manufacturing the photoelectric conversion element 5 according to the present embodiment, the tunnel dielectric is formed on the second surface 11b of the semiconductor substrate 11 having the first surface 11a and the second surface 11b opposite to the first surface 11a. Forming a body layer 20 and forming a first amorphous semiconductor layer 17 having a first conductivity type on the tunnel dielectric layer 20. The first amorphous semiconductor layer 17 includes a first impurity having the first conductivity type. The method for manufacturing the photoelectric conversion element 5 according to the present embodiment further includes forming the first amorphous semiconductor region 16 having the second conductivity type in the first amorphous semiconductor layer 17. The formation of the first amorphous semiconductor region 16 in the first amorphous semiconductor layer 17 means that a second portion different from the first conductivity type is formed in a part of the first amorphous semiconductor layer 17. Doping with a second impurity having a conductivity type.

The tunnel dielectric layer 20 suppresses recombination of carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 on the second surface 11 b of the semiconductor substrate 11. Can do. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element having improved passivation characteristics can be manufactured.

The tunnel dielectric layer 20 uses carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 as the first amorphous semiconductor layer 17 and the first amorphous semiconductor. Tunnel to region 16. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric that can efficiently collect carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11. A conversion element can be manufactured.

In the method for manufacturing the photoelectric conversion element 5 of the present embodiment, the second surface 11b of the semiconductor substrate 11 is covered with the tunnel dielectric layer 20 before the first amorphous semiconductor layer 17 is formed. . After the tunnel dielectric layer 20 and the first amorphous semiconductor layer 17 are formed on the second surface 11b of the semiconductor substrate 11, the photoelectric conversion element is exposed without exposing the second surface 11b of the semiconductor substrate 11. 5 can be manufactured. The photoelectric conversion element 5 can be manufactured without the contaminants adhering to the second surface 11b of the semiconductor substrate 11 or the second surface 11b of the semiconductor substrate 11 being roughened by etching the amorphous semiconductor layer. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

In the method for manufacturing the photoelectric conversion element 5 of the present embodiment, the first amorphous semiconductor region 16 may exist over the entire thickness of the first amorphous semiconductor layer 17. The distance between the first amorphous semiconductor region 16 and the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the second conductivity type of the first amorphous semiconductor region 16 are the first. A single amorphous semiconductor region 16 can be collected with higher efficiency. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element with improved efficiency for converting light energy into electric energy can be manufactured.

In the method for manufacturing the photoelectric conversion element 5 of the present embodiment, the concentration of the first impurity in the first amorphous semiconductor region 16 is the same as that of the first amorphous semiconductor region 16 and the first amorphous semiconductor layer. It may be constant in a direction in which 17 and 17 are alternately arranged. Therefore, after the tunnel dielectric layer 20 and the first amorphous semiconductor layer 17 are formed on the second surface 11b of the semiconductor substrate 11, the photoelectric conversion is performed without exposing the second surface 11b of the semiconductor substrate 11. The conversion element 5 can be manufactured. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

In the method of manufacturing the photoelectric conversion element 5 according to the present embodiment, before forming the first amorphous semiconductor layer 17 on the tunnel dielectric layer 20, a second i-type is formed on the tunnel dielectric layer 20. The amorphous semiconductor layer 15 may be further formed. In the second amorphous semiconductor layer 15 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the second surface 11 b of the semiconductor substrate 11. Recombination can be suppressed. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element with improved passivation characteristics and efficiency of converting light energy into electric energy can be manufactured.

In the method for manufacturing the photoelectric conversion element 5 according to the present embodiment, doping a second impurity into a part of the first amorphous semiconductor layer 17 causes a part of the first amorphous semiconductor layer 17 to be doped. Ion implantation of the second impurity may be included. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

In the method for manufacturing the photoelectric conversion element 5 according to the present embodiment, forming the tunnel dielectric layer 20 on the second surface 11b of the semiconductor substrate 11 means that the second surface 11b of the semiconductor substrate 11 is made of ozone water or excess water. It may include soaking in hydrogen oxide water. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, the tunnel dielectric layer 20 is quickly formed by a simple process of immersing the second surface 11b of the semiconductor substrate 11 in ozone water or hydrogen peroxide water. Can be done.

In the method for manufacturing the photoelectric conversion element 5 according to the present embodiment, forming the tunnel dielectric layer 20 on the second surface 11b of the semiconductor substrate 11 thermally oxidizes the second surface 11b of the semiconductor substrate 11. May be included. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, the tunnel dielectric layer 20 can be formed by a simple process of thermally oxidizing the second surface 11b of the semiconductor substrate 11.

In the method for manufacturing the photoelectric conversion element 5 according to the present embodiment, forming the tunnel dielectric layer 20 on the second surface 11b of the semiconductor substrate 11 means that the tunnel dielectric is formed on the second surface 11b of the semiconductor substrate 11. Depositing layer 20 may also be included. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, the tunnel dielectric layer 20 can be formed by a simple process of depositing the tunnel dielectric layer 20 on the second surface 11 b of the semiconductor substrate 11. .

In the method for manufacturing the photoelectric conversion element 5 of the present embodiment, the tunnel dielectric layer 20 may have a thickness of 0.2 nm or more and 5.0 nm or less. The tunnel dielectric layer 20 having a thickness of 0.2 nm or more can further improve the passivation characteristics of the photoelectric conversion element 5. The tunnel dielectric layer 20 having a thickness of 5.0 nm or less is configured to cause carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 to be generated in the first amorphous semiconductor layer. 17 and the first amorphous semiconductor region 16 can be more efficiently tunneled. According to the method of manufacturing the photoelectric conversion element 5 of the present embodiment, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11 can be collected more efficiently. A photoelectric conversion element can be manufactured.

In the method for manufacturing the photoelectric conversion element 5 according to the present embodiment, the first electrode 19 that is electrically connected to the first amorphous semiconductor layer 17 is formed on the second surface 11 b of the semiconductor substrate 11. And forming a second electrode 18 electrically connected to the first amorphous semiconductor region 16 on the second surface 11 b of the semiconductor substrate 11. According to the method of manufacturing the photoelectric conversion element 5 of the present embodiment, the first electrode 19 and the second electrode 18 are photoelectric elements that are not provided on the first surface 11a side of the semiconductor substrate 11 that is the light incident surface. The conversion element 5 can be manufactured. Light incident on the photoelectric conversion element 5 is not blocked by the first electrode 19 and the second electrode 18. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, it is possible to manufacture a photoelectric conversion element having a high short-circuit current J _SC and an improved efficiency for converting light energy into electric energy.

The method for manufacturing the photoelectric conversion element 5 of the present embodiment may further include forming the dielectric layer 14 on the first surface 11 a of the semiconductor substrate 11. When the dielectric layer 14 functions as an antireflection film, the dielectric layer 14 can cause more light to enter the photoelectric conversion element 5. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element with improved efficiency for converting light energy into electric energy can be manufactured. When the dielectric layer 14 functions as a passivation film, the carrier generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 is the first dielectric layer 14 of the semiconductor substrate 11. It is possible to suppress recombination on the surface 11a. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element with improved efficiency for converting light energy into electric energy can be manufactured.

The method for manufacturing the photoelectric conversion element 5 of the present embodiment may further include forming the third amorphous semiconductor layer 12 having i-type on the first surface 11 a of the semiconductor substrate 11. In the third amorphous semiconductor layer 12 having i-type, carriers generated in the semiconductor substrate 11 by light incident from the first surface 11 a side of the semiconductor substrate 11 are formed on the first surface 11 a of the semiconductor substrate 11. Recombination can be suppressed. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element with improved passivation characteristics and efficiency of converting light energy into electric energy can be manufactured.

The method for manufacturing the photoelectric conversion element 5 according to the present embodiment further includes forming the fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 on the first surface 11 a of the semiconductor substrate 11. You may prepare. The fourth amorphous semiconductor layer 13 having the same conductivity type as that of the semiconductor substrate 11 has the first surface 11 a of the semiconductor substrate 11 among the carriers generated in the semiconductor substrate 11 when light enters the photoelectric conversion element 5. The carrier approaching can be pushed back into the semiconductor substrate 11. The fourth amorphous semiconductor layer 13 can suppress recombination of this carrier on the first surface 11 a of the semiconductor substrate 11. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element with improved passivation characteristics and efficiency of converting light energy into electric energy can be manufactured.

The method for manufacturing the photoelectric conversion element 5 according to the present embodiment may further include forming a concavo-convex structure on the first surface 11 a of the semiconductor substrate 11. By forming a concavo-convex structure on the first surface 11 a of the semiconductor substrate 11 that is a light incident surface, more light can be incident into the photoelectric conversion element 5. According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element with improved efficiency for converting light energy into electric energy can be manufactured.

(Embodiment 9)
With reference to FIG. 3, FIG. 4, FIG. 19 to FIG. 25, FIG. 27 and FIG. The photoelectric conversion element 5 of the present embodiment has a configuration similar to that of the photoelectric conversion element 5 of the eighth embodiment. The manufacturing method of the photoelectric conversion element 5 of the present embodiment basically includes the same steps as the manufacturing method of the photoelectric conversion element 5 of the eighth embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 5 according to the eighth embodiment, the second impurity is doped in part of the first amorphous semiconductor layer 17 by the ion implantation method. On the other hand, in the method for manufacturing the photoelectric conversion element 5 of the present embodiment, doping the second impurity into a part of the first amorphous semiconductor layer 17 means that the first amorphous semiconductor layer 17 is not doped. Forming the dopant-containing film 26 containing the second impurity thereon, and transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17. Good.

Specifically, the formation of the dopant-containing film 26 containing the second impurity on the first amorphous semiconductor layer 17 means that the second impurity is formed on a part of the first amorphous semiconductor layer 17. It is also possible to apply a doping paste containing Transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 may include heat-treating the doping paste.

An example of a method for manufacturing the photoelectric conversion element 5 of the present embodiment will be described below with reference to FIGS. 3, 4, 21 to 25, 27, and 28.

3, 4, and 21 to 25, the third amorphous semiconductor layer 12, the fourth amorphous semiconductor layer 13, and the first surface 11 a of the semiconductor substrate 11 are formed. A dielectric layer 14 is formed, and a tunnel dielectric layer 20, a second amorphous semiconductor layer 15, and a first non-conductive first layer are formed on the second surface 11b of the semiconductor substrate 11. A crystalline semiconductor layer 17 is formed.

Referring to FIG. 27, a dopant-containing film 26 containing a second impurity having the second conductivity type is formed on a part of the first amorphous semiconductor layer 17. Examples of the dopant-containing film 26 include a doping paste containing a second impurity having n type such as phosphorus and a doping paste containing a second impurity having p type such as boron. The doping paste including the second impurity having n-type may include a phosphorus compound, a silicon oxide precursor, a solvent, and a thickener. The doping paste containing the second impurity having p-type may include a boron compound, a silicon oxide precursor, a solvent, and a thickener. In the present embodiment, as the dopant-containing film 26, a doping paste containing an n-type second impurity such as phosphorus may be used. The doping paste may be applied on a part of the first amorphous semiconductor layer 17 by inkjet, screen printing, or the like.

Referring to FIG. 28, the dopant-containing film 26 is heat-treated, and the second impurity contained in the dopant-containing film 26 is transferred to a part of the first amorphous semiconductor layer 17. In the present embodiment, for example, the dopant-containing film 26 that is a doping paste is heat-treated at a temperature of 700 ° C. or lower, and the second impurity contained in the dopant-containing film 26 that is a doping paste is the first amorphous semiconductor. A portion of layer 17 is doped. Thus, the first amorphous semiconductor region 16 having the second conductivity type can be formed in the first amorphous semiconductor layer 17 having the first conductivity type. The dopant-containing film 26 may be heat-treated using a heating furnace, or the dopant-containing film 26 may be heat-treated by irradiating the dopant-containing film 26 with laser light.

Then, the remaining dopant-containing film 26 is removed using a mixed solution of sulfuric acid and hydrogen peroxide solution, a mixed solution of hydrochloric acid and hydrogen peroxide solution, or hydrofluoric acid. Subsequently, the first electrode 19 and the second electrode 18 are formed on the second surface 11 b of the semiconductor substrate 11. In this way, the photoelectric conversion element 5 of the present embodiment shown in FIGS. 19 and 20 can be manufactured.

The manufacturing method of the photoelectric conversion element 5 of the present embodiment has the same effect as the manufacturing method of the photoelectric conversion element 5 of the eighth embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 5 according to the present embodiment, doping the second impurity into a part of the first amorphous semiconductor layer 17 may cause the part of the first amorphous semiconductor layer 17 to be doped. Forming a dopant-containing film 26 containing a second impurity at the same time, and transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17. . According to the method for manufacturing the photoelectric conversion element 5 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

In the method for manufacturing the photoelectric conversion element 5 of the present embodiment, the formation of the dopant-containing film 26 containing the second impurity on the first amorphous semiconductor layer 17 is the first amorphous semiconductor layer 17. A doping paste containing the second impurity may be applied on a part of the substrate. Transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 may include heat-treating the doping paste. In other words, in the method for manufacturing the photoelectric conversion element 5 of the present embodiment, doping the second impurity into a part of the first amorphous semiconductor layer 17 is a part of the first amorphous semiconductor layer 17. Applying a doping paste containing a second impurity on the part and heat-treating the doping paste may be included.

By using a doping paste as the dopant-containing film 26, the first amorphous semiconductor region 16 can be formed in the first amorphous semiconductor layer 17 with high pattern accuracy. By using a doping paste as the dopant-containing film 26, the dopant-containing film 26 can be formed on the first amorphous semiconductor layer 17 by inkjet, screen printing, or the like. According to the manufacturing method of the photoelectric conversion element 5 of this Embodiment, the photoelectric conversion element which has the improved characteristic and reliability can be manufactured by an inexpensive and simple process.

(Embodiment 10)
With reference to FIG. 3, FIG. 4, FIG. 19 to FIG. 25, FIG. 29 and FIG. 30, the photoelectric conversion element 5 of Embodiment 10 and the manufacturing method thereof will be described. The photoelectric conversion element 5 of the present embodiment has a configuration similar to that of the photoelectric conversion element 5 of the eighth embodiment. The manufacturing method of the photoelectric conversion element 5 of the present embodiment basically includes the same steps as the manufacturing method of the photoelectric conversion element 5 of the eighth embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 5 according to the eighth embodiment, the second impurity is doped in part of the first amorphous semiconductor layer 17 by the ion implantation method. On the other hand, in the method for manufacturing the photoelectric conversion element 5 of the present embodiment, doping the second impurity into a part of the first amorphous semiconductor layer 17 means that the first amorphous semiconductor layer 17 is not doped. Forming the dopant-containing film 26 containing the second impurity thereon, and transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17. Good. More specifically, transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 irradiates a part of the dopant-containing film 26 with the laser beam 27. You may include that. That is, the second impurity may be doped into a part of the first amorphous semiconductor layer 17 by a laser doping method.

An example of a method for manufacturing the photoelectric conversion element 5 of the present embodiment will be described below with reference to FIGS. 3, 4, 21 to 25, 29, and 30.

3, 4, and 21 to 25, the third amorphous semiconductor layer 12, the fourth amorphous semiconductor layer 13, and the first surface 11 a of the semiconductor substrate 11 are formed. The dielectric layer 14 is formed, and the tunnel dielectric layer 20, the second amorphous semiconductor layer 15, and the first amorphous semiconductor layer 17 are formed on the second surface 11 b of the semiconductor substrate 11. It is formed.

Referring to FIG. 29, a dopant-containing film 26 containing a second impurity having the second conductivity type is formed on the first amorphous semiconductor layer 17. Examples of the dopant-containing film 26 may include phosphorus silicate glass (PSG), boron silicate glass (BSG), and polyboron film (PBF). In the present embodiment, phosphorus silicate glass (PSG) is used as the dopant-containing film 26.

Referring to FIG. 30, a part of the dopant-containing film 26 is irradiated with laser light 27 to transfer the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17. . In the present embodiment, a part of the dopant-containing film 26 is locally heated by irradiating a part of the dopant-containing film 26 with the laser light 27. Therefore, the second impurity contained in the dopant-containing film 26 is doped only in the region corresponding to the portion irradiated with the laser beam 27 in the first amorphous semiconductor layer 17. Thus, the first amorphous semiconductor region 16 having the second conductivity type can be formed in the first amorphous semiconductor layer 17 having the first conductivity type.

By irradiating a part of the dopant-containing film 26 with the laser beam 27, a part of the dopant-containing film 26 and a part of the first amorphous semiconductor layer 17 are locally heated. Therefore, when the laser beam 27 is irradiated on a part of the dopant-containing film 26, the second impurity in the first amorphous semiconductor region 16 can be activated.

Then, the remaining dopant-containing film 26 is removed using a mixed solution of sulfuric acid and hydrogen peroxide solution, a mixed solution of hydrochloric acid and hydrogen peroxide solution, or hydrofluoric acid. In order to further activate the first impurity in the first amorphous semiconductor layer 17 and the second impurity in the first amorphous semiconductor region 16, the first amorphous semiconductor layer 17 and The first amorphous semiconductor region 16 may be further annealed. Subsequently, the first electrode 19 and the second electrode 18 are formed on the second surface 11 b of the semiconductor substrate 11. In this way, the photoelectric conversion element 5 of the present embodiment shown in FIGS. 19 and 20 can be manufactured.

In the method for manufacturing the photoelectric conversion element 5 according to the present embodiment, shifting the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 is one of the dopant-containing films 26. Irradiation of the laser beam 27 to the part may be included. That is, the second impurity may be doped into a part of the first amorphous semiconductor layer 17 by a laser doping method. The laser doping method can diffuse the dopant in a shorter time than the method of diffusing the dopant using a heating furnace. According to the manufacturing method of the photoelectric conversion element 5 of this Embodiment, the photoelectric conversion element which has the improved characteristic and reliability can be manufactured by an inexpensive and simple process.

(Embodiment 11)
With reference to FIG.19 and FIG.31, the photoelectric conversion element 6 of Embodiment 11 is demonstrated. The photoelectric conversion element 6 of the present embodiment is basically the same as the photoelectric conversion element 5 of the eighth embodiment, but differs in the following points.

The photoelectric conversion element 6 according to the present embodiment is provided in the second amorphous semiconductor layer 15 and further includes a second amorphous semiconductor region 46 having the second conductivity type. The second amorphous semiconductor layer 15 and the second amorphous semiconductor region 46 are provided on the tunnel dielectric layer 20. The second amorphous semiconductor layer 15 and the second amorphous semiconductor region 46 constitute one layer extending continuously. The second amorphous semiconductor region 46 includes a second impurity having the second conductivity type. The second amorphous semiconductor region 46 is in contact with the first amorphous semiconductor region 16. The second amorphous semiconductor region 46 may exist over the entire thickness of the second amorphous semiconductor layer 15. The second amorphous semiconductor region 46 may be in contact with the tunnel dielectric layer 20 or may not be in contact therewith.

In the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged, that is, in the first direction (for example, the x direction), the second amorphous semiconductor region 46 may have substantially the same width as the first amorphous semiconductor region 16. The concentration of the second impurity in the second amorphous semiconductor region 46 is the direction in which the first amorphous semiconductor regions 16 and the first amorphous semiconductor layers 17 are alternately arranged, that is, the first May be constant in the direction (for example, the x direction). The second amorphous semiconductor region 46 may have the second impurity concentration substantially the same as that of the first amorphous semiconductor region 16.

A method for manufacturing the photoelectric conversion element 6 according to the eleventh embodiment will be described with reference to FIGS. The manufacturing method of the photoelectric conversion element 6 of the present embodiment is basically the same as the manufacturing method of the photoelectric conversion element 5 of the eighth embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 6 according to the present embodiment, the second amorphous semiconductor layer 15 is doped with the second impurity, and the second amorphous semiconductor layer 15 is filled with the second impurity. An amorphous semiconductor region 46 may be further formed. The second amorphous semiconductor region 46 includes a second impurity having the second conductivity type. The second amorphous semiconductor region 46 is in contact with the first amorphous semiconductor region 16. Specifically, doping part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 with the second impurity may cause the first amorphous semiconductor layer 17 to be doped. The second impurity may be ion-implanted into part of the first amorphous semiconductor layer 15 and part of the second amorphous semiconductor layer 15.

Referring to FIG. 32, first amorphous semiconductor region 16 is formed in first amorphous semiconductor layer 17 and second conductive type is formed in second amorphous semiconductor layer 15. The formation of the second amorphous semiconductor region 46 means that a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 have a second conductivity type. Doping with two impurities. In other words, by doping a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 with the second impurity having the second conductivity type, The first amorphous semiconductor region 16 is formed in the amorphous semiconductor layer 17, and the second amorphous semiconductor region 46 having the second conductivity type is formed in the second amorphous semiconductor layer 15. Is formed.

A tunnel dielectric layer 20 is formed on the second surface 11 b of the semiconductor substrate 11. When the second impurity having the second conductivity type is doped into a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15, the second impurity is added to the semiconductor substrate 11. The tunnel dielectric layer 20 can reliably prevent the impurities from being doped. Therefore, the heterojunction structure between the semiconductor substrate 11 and the first amorphous semiconductor layer 17 via the second amorphous semiconductor layer 15 and the tunnel dielectric layer 20 and the tunnel dielectric layer 20 are interposed. The heterojunction structure between the semiconductor substrate 11 and the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46 can be reliably maintained.

Then, the first electrode 19 that is electrically connected to the first amorphous semiconductor layer 17 is formed on the second surface 11 b of the semiconductor substrate 11. Specifically, the first electrode 19 is formed on the first amorphous semiconductor layer 17. A second electrode 18 that is electrically connected to the first amorphous semiconductor region 16 is formed on the second surface 11 b of the semiconductor substrate 11. Specifically, the second electrode 18 is formed on the first amorphous semiconductor region 16. Thus, the photoelectric conversion element 6 of the present embodiment shown in FIGS. 19 and 31 can be manufactured.

The photoelectric conversion element 6 and its manufacturing method of the present embodiment have the same effects as the photoelectric conversion element 5 of the eighth embodiment and its manufacturing method, but are different in the following points.

The photoelectric conversion element 6 of the present embodiment may be further provided with a second amorphous semiconductor region 46 having a second conductivity type, as well as being provided in the second amorphous semiconductor layer 15. The second amorphous semiconductor region 46 may contain a second impurity having the second conductivity type. The second amorphous semiconductor region 46 may be in contact with the first amorphous semiconductor region 16. In the photoelectric conversion element 6 according to the present embodiment, the semiconductor substrate 11 includes an amorphous semiconductor region having the second conductivity type, which includes the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46, and the semiconductor substrate 11. The distance can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, the second amorphous semiconductor region 46 and the second amorphous semiconductor region 46 have the second. The carriers corresponding to the conductivity types of the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46 can be collected with higher efficiency. According to the photoelectric conversion element 6 of the present embodiment, the efficiency of converting light energy into electrical energy can be improved.

In the photoelectric conversion element 6 of the present embodiment, the tunnel dielectric layer 20 is formed on the second surface 11b of the semiconductor substrate 11, the second amorphous semiconductor layer 15 is formed on the tunnel dielectric layer 20, and the second A second amorphous semiconductor region 46 may be provided in the amorphous semiconductor layer 15. When the second amorphous semiconductor region 46 is formed by doping a part of the second amorphous semiconductor layer 15 with the second impurity having the second conductivity type, the second amorphous semiconductor region 46 is formed on the semiconductor substrate 11. The tunnel dielectric layer 20 can be surely prevented from being doped with impurities. The photoelectric conversion element 6 according to the present embodiment has a structure that can reliably prevent the second impurity in the second amorphous semiconductor region 46 from being doped into the semiconductor substrate 11. The photoelectric conversion element 6 of the present embodiment has a heterojunction structure between the semiconductor substrate 11 and the first amorphous semiconductor layer 17 via the second amorphous semiconductor layer 15 and the tunnel dielectric layer 20. The semiconductor substrate 11 and the heterojunction structure between the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46 via the tunnel dielectric layer 20 can be reliably maintained. Yes. The photoelectric conversion element 6 of the present embodiment has improved characteristics and reliability.

In the method for manufacturing the photoelectric conversion element 6 according to the present embodiment, the second amorphous semiconductor layer 15 is doped with the second impurity, and the second amorphous semiconductor layer 15 is filled with the second impurity. An amorphous semiconductor region 46 may be further formed. The second amorphous semiconductor region 46 may contain a second impurity having the second conductivity type. The second amorphous semiconductor region 46 may be in contact with the first amorphous semiconductor region 16.

According to the method for manufacturing the photoelectric conversion element 6 of the present embodiment, the amorphous semiconductor region having the second conductivity type composed of the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46, and The distance from the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, the second amorphous semiconductor region 46 and the second amorphous semiconductor region 46 have the second. The carriers corresponding to the conductivity types of the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46 can be collected with higher efficiency. According to the manufacturing method of the photoelectric conversion element 6 of this Embodiment, the photoelectric conversion element with which the efficiency which converts light energy into electrical energy was improved can be manufactured.

In the method of manufacturing the photoelectric conversion element 6 according to the present embodiment, the tunnel dielectric layer 20 is formed on the second surface 11b of the semiconductor substrate 11, and the second amorphous semiconductor is formed on the tunnel dielectric layer 20. The layer 15 is formed, and a part of the second amorphous semiconductor layer 15 is doped with the second impurity, so that the second amorphous semiconductor region 46 is formed in the second amorphous semiconductor layer 15. Forming.

In the method of manufacturing the photoelectric conversion element 6 according to the present embodiment, the second surface 11b of the semiconductor substrate 11 is covered with the tunnel dielectric layer 20 before the second amorphous semiconductor layer 15 is formed. . When the second amorphous semiconductor region 46 is formed by doping a part of the second amorphous semiconductor layer 15 with the second impurity having the second conductivity type, the second amorphous semiconductor region 46 is formed on the semiconductor substrate 11. The tunnel dielectric layer 20 can be surely prevented from being doped with impurities. According to the method for manufacturing the photoelectric conversion element 6 of the present embodiment, the semiconductor substrate 11 can be reliably prevented from being doped with the second impurity in the second amorphous semiconductor region 46. According to the method for manufacturing the photoelectric conversion element 6 of the present embodiment, the gap between the semiconductor substrate 11 and the first amorphous semiconductor layer 17 via the second amorphous semiconductor layer 15 and the tunnel dielectric layer 20 is determined. And the heterojunction structure between the semiconductor substrate 11 and the first amorphous semiconductor region 16 and the second amorphous semiconductor region 46 via the tunnel dielectric layer 20 are reliably maintained. obtain. According to the method for manufacturing the photoelectric conversion element 6 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

In the method for manufacturing the photoelectric conversion element 6 according to the present embodiment, the second impurity is doped into a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15. Ion implantation of a second impurity into part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 may be included. In one step of irradiating the ion beam 21 of the second impurity, a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 are doped with the second impurity. obtain. According to the method for manufacturing the photoelectric conversion element 6 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(Embodiment 12)
With reference to FIG. 3, FIG. 4, FIG. 21 to FIG. 25, FIG. 27, FIG. 31 and FIG. The photoelectric conversion element 6 of the present embodiment has a configuration similar to that of the photoelectric conversion element 6 of the eleventh embodiment. The manufacturing method of the photoelectric conversion element 6 of the present embodiment basically includes the same steps as the manufacturing method of the photoelectric conversion element 6 of the eleventh embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 6 according to Embodiment 11, the second impurity is introduced into part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 by ion implantation. It was doped. On the other hand, in the manufacturing method of the photoelectric conversion element 6 of the present embodiment, a part of the first amorphous semiconductor layer 17 and the first of the first amorphous semiconductor layer 17 are formed by the same method as that of the photoelectric conversion element 5 of the ninth embodiment. A part of the second amorphous semiconductor layer 15 is doped with the second impurity.

An example of a method for manufacturing the photoelectric conversion element 6 according to the present embodiment will be described below with reference to FIGS. 3, 4, 21 to 25, 27 and 33.

3, 4, and 21 to 25, the third amorphous semiconductor layer 12, the fourth amorphous semiconductor layer 13, and the first surface 11 a of the semiconductor substrate 11 are formed. The dielectric layer 14 is formed, and the tunnel dielectric layer 20, the second amorphous semiconductor layer 15, and the first amorphous semiconductor layer 17 are formed on the second surface 11 b of the semiconductor substrate 11. It is formed. Referring to FIG. 27, a dopant-containing film 26 containing a second impurity having the second conductivity type is formed on part of the first amorphous semiconductor layer 17. The dopant-containing film 26 may be a doping paste containing a second impurity having the second conductivity type.

Referring to FIG. 33, the dopant-containing film 26 is heat-treated so that the second impurity contained in the dopant-containing film 26 is part of the first amorphous semiconductor layer 17 and the second amorphous semiconductor layer 15. To some of them. In one step of heat-treating the dopant-containing film 26, a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 may be doped with the second impurity. The photoelectric conversion element of the present embodiment except that the second impurity is transferred to a part of the second amorphous semiconductor layer 15 in addition to a part of the first amorphous semiconductor layer 17. The manufacturing method 6 is the same as the manufacturing method of the photoelectric conversion element 5 of the ninth embodiment.

The manufacturing method of the photoelectric conversion element 6 of the present embodiment has the effect of the manufacturing method of the photoelectric conversion element 6 of the eleventh embodiment and the effect of the manufacturing method of the photoelectric conversion element 5 of the ninth embodiment.

In the method of manufacturing the photoelectric conversion element 6 according to the present embodiment, doping a second impurity into a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 Forming a dopant-containing film 26 containing a second impurity on the first amorphous semiconductor layer 17, and applying the second impurity contained in the dopant-containing film 26 to one of the first amorphous semiconductor layer 17 And transition to a part of the second amorphous semiconductor layer 15. In one step of transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15, A part of the crystalline semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 may be doped with the second impurity. According to the method for manufacturing the photoelectric conversion element 6 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

In the method for manufacturing the photoelectric conversion element 6 according to the present embodiment, forming the dopant-containing film 26 containing the second impurity on the first amorphous semiconductor layer 17 is the first amorphous semiconductor layer 17. A doping paste containing the second impurity may be applied on a part of the substrate. Transferring the second impurity contained in the dopant-containing film 26 to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 means that the doping paste is heat-treated. May be included. In one step of heat-treating the dopant-containing film 26 (doping paste), a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15 are doped with the second impurity. obtain. According to the method for manufacturing the photoelectric conversion element 6 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(Embodiment 13)
With reference to FIG. 3, FIG. 4, FIG. 21 to FIG. 25, FIG. 29, FIG. 31 and FIG. The photoelectric conversion element 6 of the present embodiment has a configuration similar to that of the photoelectric conversion element 6 of the eleventh embodiment. The manufacturing method of the photoelectric conversion element 6 of the present embodiment basically includes the same steps as the manufacturing method of the photoelectric conversion element 6 of the eleventh embodiment, but differs in the following points.

In the method for manufacturing the photoelectric conversion element 6 according to Embodiment 11, the second impurity is introduced into part of the first amorphous semiconductor layer 17 and part of the second amorphous semiconductor layer 15 by ion implantation. It was doped. On the other hand, in the manufacturing method of the photoelectric conversion element 6 according to the present embodiment, as in the manufacturing method of the photoelectric conversion element 5 according to the tenth embodiment, the first amorphous semiconductor layer 17 is formed by laser doping. The second impurity is doped into the portion and part of the second amorphous semiconductor layer 15.

An example of a method for manufacturing the photoelectric conversion element 6 of the present embodiment will be described below with reference to FIGS. 3, 4, 21 to 25, 29, and 34.

Referring to FIG. 29, a dopant-containing film 26 containing a second impurity having the second conductivity type is formed on the first amorphous semiconductor layer 17. The dopant-containing film 26 may be a doping paste containing a second impurity having the second conductivity type. Referring to FIG. 34, a part of the dopant-containing film 26 is irradiated with a laser beam 27 so that the second impurity contained in the dopant-containing film 26 is part of the first amorphous semiconductor layer 17 and the second impurity. To a part of the amorphous semiconductor layer 15. In one step of irradiating a part of the dopant-containing film 26 with the laser beam 27, a second impurity is added to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15. Can be doped. The photoelectric conversion element of the present embodiment except that the second impurity is transferred to a part of the second amorphous semiconductor layer 15 in addition to a part of the first amorphous semiconductor layer 17. The manufacturing method 6 is the same as the manufacturing method of the photoelectric conversion element 5 of the tenth embodiment.

The manufacturing method of the photoelectric conversion element 6 of the present embodiment has the effect of the manufacturing method of the photoelectric conversion element 6 of the eleventh embodiment and the effect of the manufacturing method of the photoelectric conversion element 5 of the tenth embodiment. In the method for manufacturing the photoelectric conversion element 6 according to the present embodiment, the second impurity contained in the dopant-containing film 26 is part of the first amorphous semiconductor layer 17 and the second amorphous semiconductor layer 15. The transition to the portion may include irradiating a part of the dopant-containing film 26 with the laser beam 27. In one step of irradiating a part of the dopant-containing film 26 with the laser beam 27, a second impurity is added to a part of the first amorphous semiconductor layer 17 and a part of the second amorphous semiconductor layer 15. Can be doped. According to the method for manufacturing the photoelectric conversion element 6 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(Embodiment 14)
With reference to FIG. 35, the photoelectric conversion element 7 of Embodiment 14 will be described. Although the photoelectric conversion element 7 of this Embodiment is equipped with the structure similar to the photoelectric conversion element 5 of Embodiment 8, it differs in the following points.

The photoelectric conversion element 7 of the present embodiment does not include the second amorphous semiconductor layer 15. The first amorphous semiconductor layer 17 is provided on the tunnel dielectric layer 20 and is in direct contact with the tunnel dielectric layer 20. The first amorphous semiconductor region 16 may be in direct contact with the tunnel dielectric layer 20. The first amorphous semiconductor region 16 may exist over the entire thickness of the first amorphous semiconductor layer 17. The first amorphous semiconductor region 16 may or may not be in contact with the tunnel dielectric layer 20.

The manufacturing method of the photoelectric conversion element 7 of the present embodiment is the same as the manufacturing method of the photoelectric conversion element 5 of the eighth to tenth embodiments except that the second amorphous semiconductor layer 15 is formed. It is the same. Specifically, in the method for manufacturing the photoelectric conversion element 7 according to the present embodiment, the formation of the first amorphous semiconductor layer 17 on the second surface 11b of the semiconductor substrate 11 includes the tunnel dielectric layer 20. Forming the first amorphous semiconductor layer 17 in direct contact with the first amorphous semiconductor layer 17 may be included.

The photoelectric conversion element 7 and the manufacturing method thereof according to the present embodiment have the same effects as the photoelectric conversion element 5 and the manufacturing method thereof according to the eighth to tenth embodiments, but are different in the following points.

In the photoelectric conversion element 7 of the present embodiment, the first amorphous semiconductor layer 17 may be in direct contact with the tunnel dielectric layer 20. Since the first amorphous semiconductor layer 17 is in direct contact with the tunnel dielectric layer 20, the distance between the first amorphous semiconductor layer 17 and the semiconductor substrate 11 and the first amorphous semiconductor layer 17 are within the range. The distance between the provided first amorphous semiconductor region 16 and the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the first conductivity type of the first amorphous semiconductor layer 17 are first One amorphous semiconductor layer 17 can be collected with higher efficiency. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the second conductivity type of the first amorphous semiconductor region 16 are the first. A single amorphous semiconductor region 16 can be collected with higher efficiency. According to the photoelectric conversion element 7 of the present embodiment, the efficiency of converting light energy into electrical energy can be improved.

The photoelectric conversion element 7 according to the present embodiment includes a tunnel dielectric layer 20 on the second surface 11 b of the semiconductor substrate 11 and a first amorphous semiconductor layer 17 that is in direct contact with the tunnel dielectric layer 20. ing. In the photoelectric conversion element 7 of the present embodiment, the tunnel dielectric layer 20 exists between the second surface 11 b of the semiconductor substrate 11 and the first amorphous semiconductor layer 17. The tunnel dielectric layer 20 ensures that the semiconductor substrate 11 is doped with the first impurity when the first amorphous semiconductor layer 17 containing the first impurity having the first conductivity type is formed. Can be prevented. When the first amorphous semiconductor region 16 is formed by doping a part of the first amorphous semiconductor layer 17 with the second impurity having the second conductivity type, the second amorphous semiconductor layer 17 is formed on the semiconductor substrate 11. The tunnel dielectric layer 20 can be surely prevented from being doped with impurities. In the photoelectric conversion element 7 of the present embodiment, the semiconductor substrate 11 is doped with the first impurity in the first amorphous semiconductor layer 17 and the second impurity in the first amorphous semiconductor region 16. It has a structure that can be surely prevented. The photoelectric conversion element 7 of the present embodiment includes a heterojunction structure between the semiconductor substrate 11 and the first amorphous semiconductor layer 17 via the tunnel dielectric layer 20 and a semiconductor via the tunnel dielectric layer 20. A structure in which the heterojunction structure between the substrate 11 and the first amorphous semiconductor region 16 can be reliably maintained is provided. The photoelectric conversion element 7 of the present embodiment has improved characteristics and reliability.

In the method of manufacturing the photoelectric conversion element 7 of the present embodiment, the formation of the first amorphous semiconductor layer 17 on the tunnel dielectric layer 20 means that the first amorphous semiconductor directly in contact with the tunnel dielectric layer 20 is used. It may include forming the semiconductor layer 17. Since the first amorphous semiconductor layer 17 is in direct contact with the tunnel dielectric layer 20, the distance between the first amorphous semiconductor layer 17 and the semiconductor substrate 11 and the first amorphous semiconductor layer 17 are within the range. The distance between the provided first amorphous semiconductor region 16 and the semiconductor substrate 11 can be reduced. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the first conductivity type of the first amorphous semiconductor layer 17 are first One amorphous semiconductor layer 17 can be collected with higher efficiency. Of the carriers generated in the semiconductor substrate 11 by light incident from the first surface 11a side of the semiconductor substrate 11, carriers corresponding to the second conductivity type of the first amorphous semiconductor region 16 are the first. A single amorphous semiconductor region 16 can be collected with higher efficiency. According to the manufacturing method of the photoelectric conversion element 7 of this Embodiment, the photoelectric conversion element in which the efficiency which converts light energy into electrical energy was improved can be manufactured.

In the method of manufacturing the photoelectric conversion element 7 according to the present embodiment, the tunnel dielectric layer 20 is formed on the second surface 11b of the semiconductor substrate 11, and the first amorphous material that is in direct contact with the tunnel dielectric layer 20 is used. Forming a semiconductor layer 17. In the method for manufacturing the photoelectric conversion element 7 of the present embodiment, the second surface 11b of the semiconductor substrate 11 is covered with the tunnel dielectric layer 20 before the first amorphous semiconductor layer 17 is formed. . According to the method for manufacturing the photoelectric conversion element 7 of the present embodiment, the first amorphous semiconductor layer 17 containing the first impurity having the first conductivity type is formed on the semiconductor substrate 11 when the first amorphous semiconductor layer 17 is formed. The tunnel dielectric layer 20 can reliably prevent the impurities from being doped. When the first amorphous semiconductor region 16 is formed by doping a part of the first amorphous semiconductor layer 17 with the second impurity having the second conductivity type, the second amorphous semiconductor layer 17 is formed on the semiconductor substrate 11. The tunnel dielectric layer 20 can be surely prevented from being doped with impurities. According to the method for manufacturing the photoelectric conversion element 7 of the present embodiment, the first impurity in the first amorphous semiconductor layer 17 and the second impurity in the first amorphous semiconductor region 16 are the semiconductor. It can be reliably prevented that the substrate 11 is doped. According to the method of manufacturing the photoelectric conversion element 7 of the present embodiment, the heterojunction structure between the semiconductor substrate 11 and the first amorphous semiconductor layer 17 via the tunnel dielectric layer 20, and the tunnel dielectric layer The heterojunction structure between the semiconductor substrate 11 and the first amorphous semiconductor region 16 via 20 can be reliably maintained. According to the method for manufacturing the photoelectric conversion element 7 of the present embodiment, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

[Appendix]
(1) The photoelectric conversion element according to the embodiment disclosed herein is provided on a semiconductor substrate having a first surface and a second surface opposite to the first surface, and on the second surface. A first amorphous semiconductor layer having a first conductivity type, and a first amorphous semiconductor region provided on the second surface and having a second conductivity type different from the first conductivity type With. The first amorphous semiconductor layer includes a first impurity having a first conductivity type. The first amorphous semiconductor region includes a first impurity and a second impurity having a second conductivity type. The first amorphous semiconductor layer and the first amorphous semiconductor region constitute one layer that extends continuously.

A structure that can be manufactured without exposing the second surface of the semiconductor substrate after the first amorphous semiconductor layer is formed on the second surface of the semiconductor substrate is described in the embodiment disclosed herein. The photoelectric conversion element is provided. Embodiments disclosed herein include a structure that can be manufactured without a contaminant adhering to the second surface of a semiconductor substrate or the second surface of a semiconductor substrate being roughened by etching an amorphous semiconductor layer. The photoelectric conversion element is provided. The photoelectric conversion element of the embodiment disclosed herein has improved characteristics and reliability.

(2) In the photoelectric conversion element of the embodiment disclosed herein, the first amorphous semiconductor region may exist over the entire thickness of the first amorphous semiconductor layer. The distance between the first amorphous semiconductor region and the semiconductor substrate can be reduced. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the second conductivity type of the first amorphous semiconductor region is the first amorphous. Higher efficiency can be collected by the quality semiconductor region. According to the photoelectric conversion element of the embodiment disclosed herein, the efficiency of converting light energy into electric energy can be improved.

(3) In the photoelectric conversion element of the embodiment disclosed herein, the concentration of the first impurity in the first amorphous semiconductor region is the same as that of the first amorphous semiconductor region and the first amorphous semiconductor. It may be constant in the direction in which the layers are arranged alternately. A structure that can be manufactured without exposing the second surface of the semiconductor substrate after the first amorphous semiconductor layer is formed on the second surface of the semiconductor substrate is described in the embodiment disclosed herein. The photoelectric conversion element is provided. The photoelectric conversion element of the embodiment disclosed herein has improved characteristics and reliability.

(4) In the photoelectric conversion element of the embodiment disclosed herein, the first amorphous semiconductor layer may be in direct contact with the second surface of the semiconductor substrate. Since the first amorphous semiconductor layer is in direct contact with the second surface of the semiconductor substrate, the distance between the first amorphous semiconductor layer and the semiconductor substrate and the first amorphous semiconductor layer are provided in the first amorphous semiconductor layer. The distance between the first amorphous semiconductor region and the semiconductor substrate can be reduced. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the first conductivity type of the first amorphous semiconductor layer is the first amorphous. It can be collected with higher efficiency by the quality semiconductor layer. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the second conductivity type of the first amorphous semiconductor region is the first amorphous. Higher efficiency can be collected by the quality semiconductor region. According to the photoelectric conversion element of the embodiment disclosed herein, the efficiency of converting light energy into electric energy can be improved.

(5) In the photoelectric conversion element of the embodiment disclosed herein, the photoelectric conversion element between the first amorphous semiconductor layer and the second surface of the semiconductor substrate and between the first amorphous semiconductor region and the semiconductor substrate. A second amorphous semiconductor layer having i-type may be further provided between the two surfaces. The second amorphous semiconductor layer having i-type suppresses recombination of carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate on the second surface of the semiconductor substrate. can do. According to the photoelectric conversion element of the embodiment disclosed herein, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

(6) The photoelectric conversion element according to the embodiment disclosed herein further includes a second amorphous semiconductor region having a second conductivity type, as well as being provided in the second amorphous semiconductor layer. Also good. The second amorphous semiconductor region may include a second impurity. The second amorphous semiconductor region may be in contact with the first amorphous semiconductor region. In the photoelectric conversion element according to the embodiment disclosed herein, an amorphous semiconductor region having the second conductivity type including the first amorphous semiconductor region and the second amorphous semiconductor region, and the semiconductor substrate The distance can be reduced. Corresponding to the second conductivity type of the first amorphous semiconductor region and the second amorphous semiconductor region among the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate Carriers to be collected can be collected with higher efficiency by the first amorphous semiconductor region and the second amorphous semiconductor region. According to the photoelectric conversion element of the embodiment disclosed herein, the efficiency of converting light energy into electric energy can be improved.

(7) The photoelectric conversion element according to the embodiment disclosed herein is provided on a semiconductor substrate having a first surface and a second surface opposite to the first surface, and the second surface. A tunnel dielectric layer, provided on the tunnel dielectric layer, provided on the tunnel dielectric layer, and different from the first conductivity type, provided on the tunnel dielectric layer. And a first amorphous semiconductor region having a second conductivity type. The first amorphous semiconductor layer includes a first impurity having a first conductivity type. The first amorphous semiconductor region includes a first impurity and a second impurity having a second conductivity type. The first amorphous semiconductor layer and the first amorphous semiconductor region constitute one layer that extends continuously.

The tunnel dielectric layer can suppress recombination of carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate on the second surface of the semiconductor substrate. The photoelectric conversion elements of the embodiments disclosed herein have improved passivation characteristics.

The tunnel dielectric layer tunnels carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate to the first amorphous semiconductor layer and the first amorphous semiconductor region. According to the photoelectric conversion element of the embodiment disclosed herein, carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate can be efficiently collected.

In the photoelectric conversion element of the embodiment disclosed herein, after the tunnel dielectric layer and the first amorphous semiconductor layer are formed on the second surface of the semiconductor substrate, the second surface of the semiconductor substrate is formed. It has a structure that can be manufactured without exposure. Embodiments disclosed herein include a structure that can be manufactured without a contaminant adhering to the second surface of a semiconductor substrate or the second surface of a semiconductor substrate being roughened by etching an amorphous semiconductor layer. The photoelectric conversion element is provided. The photoelectric conversion element of the embodiment disclosed herein has improved characteristics and reliability.

(8) In the photoelectric conversion element of the embodiment disclosed herein, the first amorphous semiconductor region may exist over the entire thickness of the first amorphous semiconductor layer. The distance between the first amorphous semiconductor region and the semiconductor substrate can be reduced. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the second conductivity type of the first amorphous semiconductor region is the first amorphous. Higher efficiency can be collected by the quality semiconductor region. According to the photoelectric conversion element of the embodiment disclosed herein, the efficiency of converting light energy into electric energy can be improved.

(9) In the photoelectric conversion element of the embodiment disclosed herein, the concentration of the first impurity in the first amorphous semiconductor region is the same as that of the first amorphous semiconductor region and the first amorphous semiconductor. It may be constant in the direction in which the layers are arranged alternately. Therefore, after the tunnel dielectric layer and the first amorphous semiconductor layer are formed on the second surface of the semiconductor substrate, a structure that can be manufactured without exposing the second surface of the semiconductor substrate is here. The photoelectric conversion element of the disclosed embodiment is provided. The photoelectric conversion element of the embodiment disclosed herein has improved characteristics and reliability.

(10) In the photoelectric conversion element of the embodiment disclosed herein, the first amorphous semiconductor layer may be in direct contact with the tunnel dielectric layer. Since the first amorphous semiconductor layer is in direct contact with the tunnel dielectric layer, the distance between the first amorphous semiconductor layer and the semiconductor substrate and the first amorphous semiconductor layer provided in the first amorphous semiconductor layer The distance between the amorphous semiconductor region and the semiconductor substrate can be reduced. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the first conductivity type of the first amorphous semiconductor layer is the first amorphous. It can be collected with higher efficiency by the quality semiconductor layer. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the second conductivity type of the first amorphous semiconductor region is the first amorphous. Higher efficiency can be collected by the quality semiconductor region. According to the photoelectric conversion element of the embodiment disclosed herein, the efficiency of converting light energy into electric energy can be improved.

The photoelectric conversion element according to the embodiment disclosed herein includes a tunnel dielectric layer on the second surface of the semiconductor substrate, and a first amorphous semiconductor layer in direct contact with the tunnel dielectric layer. . In the photoelectric conversion element according to the embodiment disclosed herein, a tunnel dielectric layer exists between the second surface of the semiconductor substrate and the first amorphous semiconductor layer. The tunnel dielectric layer reliably prevents the semiconductor substrate from being doped with the first impurity when the first amorphous semiconductor layer containing the first impurity having the first conductivity type is formed. Can do. The semiconductor substrate is doped with the second impurity when the first amorphous semiconductor region is formed by doping a part of the first amorphous semiconductor layer with the second impurity having the second conductivity type. The tunnel dielectric layer can be reliably prevented. As described above, in the photoelectric conversion element of the embodiment disclosed herein, the first impurity in the first amorphous semiconductor layer and the second impurity in the first amorphous semiconductor region are semiconductors. It has a structure that can reliably prevent the substrate from being doped. The photoelectric conversion element of the embodiment disclosed herein includes a heterojunction structure between a semiconductor substrate and a first amorphous semiconductor layer via a tunnel dielectric layer, and a semiconductor substrate via a tunnel dielectric layer And a heterojunction structure between the first amorphous semiconductor region and the first amorphous semiconductor region. The photoelectric conversion element of the embodiment disclosed herein has improved characteristics and reliability.

(11) The photoelectric conversion element according to the embodiment disclosed herein includes a gap between the first amorphous semiconductor layer and the tunnel dielectric layer and a gap between the first amorphous semiconductor region and the tunnel dielectric layer. Further, an i-type second amorphous semiconductor layer may be further provided. The second amorphous semiconductor layer having i-type suppresses recombination of carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate on the second surface of the semiconductor substrate. can do. According to the photoelectric conversion element of the embodiment disclosed herein, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

(12) The photoelectric conversion element according to the embodiment disclosed herein further includes a second amorphous semiconductor region having a second conductivity type, as well as being provided in the second amorphous semiconductor layer. Also good. The second amorphous semiconductor region may include a second impurity. The second amorphous semiconductor region may be in contact with the first amorphous semiconductor region.

In the photoelectric conversion element according to the embodiment disclosed herein, an amorphous semiconductor region having the second conductivity type including the first amorphous semiconductor region and the second amorphous semiconductor region, and the semiconductor substrate The distance can be reduced. Corresponding to the second conductivity type of the first amorphous semiconductor region and the second amorphous semiconductor region among the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate Carriers to be collected can be collected with higher efficiency by the first amorphous semiconductor region and the second amorphous semiconductor region. According to the photoelectric conversion element of the embodiment disclosed herein, the efficiency of converting light energy into electric energy can be improved.

The photoelectric conversion element of the embodiment disclosed herein includes a tunnel dielectric layer on the second surface of the semiconductor substrate, a second amorphous semiconductor layer on the tunnel dielectric layer, and a second amorphous layer. A second amorphous semiconductor region may be provided in the crystalline semiconductor layer. When the second amorphous semiconductor region is formed by doping the second amorphous semiconductor layer with a second impurity having the second conductivity type in part of the second amorphous semiconductor layer, the semiconductor substrate is doped with the second impurity. The tunnel dielectric layer can be reliably prevented. The photoelectric conversion element of the embodiment disclosed here has a structure that can reliably prevent the second impurity in the second amorphous semiconductor region from being doped into the semiconductor substrate. The photoelectric conversion element of the embodiment disclosed herein includes a heterojunction structure between the semiconductor substrate and the first amorphous semiconductor layer via the second amorphous semiconductor layer and the tunnel dielectric layer, A structure in which the heterojunction structure between the semiconductor substrate and the first amorphous semiconductor region and the second amorphous semiconductor region via the tunnel dielectric layer can be reliably maintained is provided. The photoelectric conversion element of the embodiment disclosed herein has improved characteristics and reliability.

(13) In the photoelectric conversion element of the embodiment disclosed herein, the tunnel dielectric layer may have a thickness of 0.2 nm to 5.0 nm. The tunnel dielectric layer having a thickness of 0.2 nm or more can further improve the passivation characteristics of the photoelectric conversion element. The tunnel dielectric layer having a thickness of 5.0 nm or less allows carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate to be converted into the first amorphous semiconductor layer and the first amorphous semiconductor layer. Tunneling to the amorphous semiconductor region can be performed more efficiently. According to the photoelectric conversion element of the embodiment disclosed herein, carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate can be collected more efficiently.

(14) The photoelectric conversion element of the embodiment disclosed herein is provided on the second surface of the semiconductor substrate, and has a first electrode electrically connected to the first amorphous semiconductor layer The semiconductor device may further include a second electrode provided on the second surface of the semiconductor substrate and electrically connected to the first amorphous semiconductor region. The first electrode and the second electrode are not provided on the first surface side of the semiconductor substrate which is a light incident surface. Light incident on the photoelectric conversion element is not blocked by the first electrode and the second electrode. According to the photoelectric conversion element of the embodiment disclosed herein, a high short-circuit current J _SC can be obtained, and the efficiency of converting light energy into electrical energy can be improved.

(15) The photoelectric conversion element of the embodiment disclosed herein may further include a dielectric layer on the first surface of the semiconductor substrate. When the dielectric layer functions as an antireflection film, the dielectric layer can allow more light to enter the photoelectric conversion element. According to the photoelectric conversion element of the embodiment disclosed herein, the efficiency of converting light energy into electric energy can be improved. When the dielectric layer functions as a passivation film, the dielectric layer is such that carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate are recombined on the first surface of the semiconductor substrate. Can be suppressed. According to the photoelectric conversion element of the embodiment disclosed herein, the efficiency of converting light energy into electric energy can be improved.

(16) The photoelectric conversion element of the embodiment disclosed herein may further include an i-type third amorphous semiconductor layer on the first surface of the semiconductor substrate. The third amorphous semiconductor layer having i-type suppresses recombination of carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate on the first surface of the semiconductor substrate. can do. According to the photoelectric conversion element of the embodiment disclosed herein, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

(17) The photoelectric conversion element of the embodiment disclosed herein may further include a fourth amorphous semiconductor layer having the same conductivity type as the semiconductor substrate, on the first surface of the semiconductor substrate. The fourth amorphous semiconductor layer having the same conductivity type as that of the semiconductor substrate has a carrier that is close to the first surface of the semiconductor substrate among carriers generated in the semiconductor substrate when light is incident on the photoelectric conversion element. It can be pushed back into the substrate. The fourth amorphous semiconductor layer can suppress recombination of the carriers on the first surface of the semiconductor substrate. According to the photoelectric conversion element of the embodiment disclosed herein, the passivation characteristics and the efficiency of converting light energy into electric energy can be improved.

(18) In the photoelectric conversion element of the embodiment disclosed herein, the first surface of the semiconductor substrate may include an uneven structure. By providing the concavo-convex structure on the first surface of the semiconductor substrate which is the light incident surface, more light can be incident into the photoelectric conversion element. According to the photoelectric conversion element of the embodiment disclosed herein, the efficiency of converting light energy into electric energy can be improved.

(19) A method for manufacturing a photoelectric conversion element according to an embodiment disclosed herein includes a first surface and a second surface of a semiconductor substrate having a second surface opposite to the first surface. Forming a first amorphous semiconductor layer having a first conductivity type. The first amorphous semiconductor layer includes a first impurity having a first conductivity type. The manufacturing method of the photoelectric conversion element according to the embodiment disclosed herein further includes forming a first amorphous semiconductor region having the second conductivity type in the first amorphous semiconductor layer. The formation of the first amorphous semiconductor region in the first amorphous semiconductor layer means that a part of the first amorphous semiconductor layer has a second conductivity type different from the first conductivity type. Doping with a second impurity.

After the first amorphous semiconductor layer is formed on the second surface of the semiconductor substrate, the photoelectric conversion element can be manufactured without exposing the second surface of the semiconductor substrate. The photoelectric conversion element can be manufactured without a contaminant adhering to the second surface of the semiconductor substrate and without causing the second surface of the semiconductor substrate to be roughened by etching the amorphous semiconductor layer. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

(20) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the second surface of the semiconductor substrate having the first surface and the second surface opposite to the first surface is provided. Forming a first amorphous semiconductor layer having a first conductivity type. The first amorphous semiconductor layer includes a first impurity having a first conductivity type. The manufacturing method of the photoelectric conversion element according to the embodiment disclosed herein further includes forming a first amorphous semiconductor region having the second conductivity type in the first amorphous semiconductor layer. The formation of the first amorphous semiconductor region in the first amorphous semiconductor layer means that a part of the first amorphous semiconductor layer has a second conductivity type different from the first conductivity type. Doping with a second impurity.

The tunnel dielectric layer can suppress recombination of carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate on the second surface of the semiconductor substrate. According to the photoelectric conversion element manufacturing method of the embodiment disclosed herein, a photoelectric conversion element having improved passivation characteristics can be manufactured.

The tunnel dielectric layer tunnels carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate to the first amorphous semiconductor layer and the first amorphous semiconductor region. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, photoelectrics that can efficiently collect carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate. A conversion element can be manufactured.

In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the second surface of the semiconductor substrate is covered with the tunnel dielectric layer before the first amorphous semiconductor layer is formed. Therefore, after the tunnel dielectric layer and the first amorphous semiconductor layer are formed on the second surface of the semiconductor substrate, the photoelectric conversion element can be manufactured without exposing the second surface of the semiconductor substrate. . The photoelectric conversion element can be manufactured without a contaminant adhering to the second surface of the semiconductor substrate and without causing the second surface of the semiconductor substrate to be roughened by etching the amorphous semiconductor layer. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

(21) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the first amorphous semiconductor region may exist over the entire thickness of the first amorphous semiconductor layer. The distance between the first amorphous semiconductor region and the semiconductor substrate can be reduced. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the second conductivity type of the first amorphous semiconductor region is the first amorphous. Higher efficiency can be collected by the quality semiconductor region. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

(22) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the concentration of the first impurity in the first amorphous semiconductor region is different from that in the first amorphous semiconductor region. It may be constant in the direction in which the crystalline semiconductor layers are alternately arranged. Therefore, after the first amorphous semiconductor layer is formed on the second surface of the semiconductor substrate, the photoelectric conversion element can be manufactured without exposing the second surface of the semiconductor substrate. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

(23) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the concentration of the first impurity in the first amorphous semiconductor region is different from that in the first amorphous semiconductor region. It may be constant in the direction in which the crystalline semiconductor layers are alternately arranged. Therefore, after the tunnel dielectric layer and the first amorphous semiconductor layer are formed on the second surface of the semiconductor substrate, the photoelectric conversion element can be manufactured without exposing the second surface of the semiconductor substrate. . According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

(24) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, forming the first amorphous semiconductor layer on the second surface of the semiconductor substrate is the second surface of the semiconductor substrate. Forming a first amorphous semiconductor layer in direct contact with the first amorphous semiconductor layer. Since the first amorphous semiconductor layer is in direct contact with the second surface of the semiconductor substrate, the distance between the first amorphous semiconductor layer and the semiconductor substrate and the first amorphous semiconductor layer are provided in the first amorphous semiconductor layer. The distance between the first amorphous semiconductor region and the semiconductor substrate can be reduced. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the first conductivity type of the first amorphous semiconductor layer is the first amorphous. It can be collected with higher efficiency by the quality semiconductor layer. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the second conductivity type of the first amorphous semiconductor region is the first amorphous. Higher efficiency can be collected by the quality semiconductor region. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

(25) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, forming the first amorphous semiconductor layer on the tunnel dielectric layer includes the step of directly contacting the tunnel dielectric layer. It may also include forming an amorphous semiconductor layer. Since the first amorphous semiconductor layer is in direct contact with the tunnel dielectric layer, the distance between the first amorphous semiconductor layer and the semiconductor substrate and the first amorphous semiconductor layer provided in the first amorphous semiconductor layer The distance between the amorphous semiconductor region and the semiconductor substrate can be reduced. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the first conductivity type of the first amorphous semiconductor layer is the first amorphous. It can be collected with higher efficiency by the quality semiconductor layer. Of the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate, the carrier corresponding to the second conductivity type of the first amorphous semiconductor region is the first amorphous. Higher efficiency can be collected by the quality semiconductor region. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

According to the method of manufacturing a photoelectric conversion element of the embodiment disclosed herein, a tunnel dielectric layer is formed on a second surface of a semiconductor substrate, and a first amorphous semiconductor that is in direct contact with the tunnel dielectric layer Forming a layer. In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the second surface of the semiconductor substrate is covered with the tunnel dielectric layer before the first amorphous semiconductor layer is formed. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, the first amorphous semiconductor layer containing the first impurity having the first conductivity type is formed on the semiconductor substrate when the first amorphous semiconductor layer is formed. The tunnel dielectric layer can be reliably prevented from being doped with one impurity. The semiconductor substrate is doped with the second impurity when the first amorphous semiconductor region is formed by doping a part of the first amorphous semiconductor layer with the second impurity having the second conductivity type. The tunnel dielectric layer can be reliably prevented. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, the first impurity in the first amorphous semiconductor layer and the second impurity in the first amorphous semiconductor region are It can be reliably prevented that the semiconductor substrate is doped. According to the method of manufacturing the photoelectric conversion element of the embodiment disclosed herein, the heterojunction structure between the semiconductor substrate and the first amorphous semiconductor layer via the tunnel dielectric layer, and the tunnel dielectric layer Thus, the heterojunction structure between the semiconductor substrate and the first amorphous semiconductor region can be reliably maintained. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

(26) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the second surface of the semiconductor substrate is formed before forming the first amorphous semiconductor layer on the second surface of the semiconductor substrate. A second amorphous semiconductor layer having i-type may be further formed thereon. The second amorphous semiconductor layer having i-type suppresses recombination of carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate on the second surface of the semiconductor substrate. can do. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved passivation characteristics and efficiency of converting light energy into electric energy can be manufactured.

(27) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, before forming the first amorphous semiconductor layer on the tunnel dielectric layer, the i-type is formed on the tunnel dielectric layer. It may further include forming a second amorphous semiconductor layer. The second amorphous semiconductor layer having i-type suppresses recombination of carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate on the second surface of the semiconductor substrate. can do. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved passivation characteristics and efficiency of converting light energy into electric energy can be manufactured.

(28) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, doping the second impurity into a part of the first amorphous semiconductor layer may be the first amorphous semiconductor layer. A second impurity may be ion-implanted into a part of the first impurity. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(29) In the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, doping the second impurity into a part of the first amorphous semiconductor layer may be the first amorphous semiconductor layer. Forming a dopant-containing film containing a second impurity thereon and transferring the second impurity contained in the dopant-containing film to a part of the first amorphous semiconductor layer may be included. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(30) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, forming the dopant-containing film containing the second impurity on the first amorphous semiconductor layer is the first amorphous The doping paste containing the second impurity may be applied on a part of the crystalline semiconductor layer. Transferring the second impurity contained in the dopant-containing film to a part of the first amorphous semiconductor layer may include heat-treating the doping paste. That is, in the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, doping a second impurity into a part of the first amorphous semiconductor layer Applying a doping paste containing a second impurity on a part and heat-treating the doping paste may be included.

By using a doping paste as the dopant-containing film, the first amorphous semiconductor region can be formed in the first amorphous semiconductor layer with high pattern accuracy. By using a doping paste as the dopant-containing film, the dopant-containing film can be formed on the first amorphous semiconductor layer by inkjet, screen printing, or the like. Therefore, according to the photoelectric conversion element manufacturing method of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured at a low cost and with a simple process.

(31) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, transferring the second impurity contained in the dopant-containing film to a part of the first amorphous semiconductor layer includes dopant-containing. Irradiation of a part of the film with laser light may be included. That is, the second impurity may be doped into part of the first amorphous semiconductor layer by a laser doping method. The laser doping method can diffuse the dopant in a shorter time than the method of diffusing the dopant using a heating furnace. Therefore, according to the photoelectric conversion element manufacturing method of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured at a low cost and with a simple process.

(32) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, a second impurity is doped into a part of the second amorphous semiconductor layer, so that the inside of the second amorphous semiconductor layer The method may further comprise forming a second amorphous semiconductor region. The second amorphous semiconductor region may include a second impurity. The second amorphous semiconductor region may be in contact with the first amorphous semiconductor region. According to the method of manufacturing a photoelectric conversion element of the embodiment disclosed herein, the amorphous semiconductor region having the second conductivity type, which includes the first amorphous semiconductor region and the second amorphous semiconductor region. The distance between the semiconductor substrate and the semiconductor substrate can be reduced. Corresponding to the second conductivity type of the first amorphous semiconductor region and the second amorphous semiconductor region among the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate Carriers to be collected can be collected with higher efficiency by the first amorphous semiconductor region and the second amorphous semiconductor region. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

(33) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, a second impurity is doped into a part of the second amorphous semiconductor layer, and the inside of the second amorphous semiconductor layer The method may further comprise forming a second amorphous semiconductor region. The second amorphous semiconductor region may include a second impurity. The second amorphous semiconductor region may be in contact with the first amorphous semiconductor region. According to the method of manufacturing a photoelectric conversion element of the embodiment disclosed herein, the amorphous semiconductor region having the second conductivity type, which includes the first amorphous semiconductor region and the second amorphous semiconductor region. The distance between the semiconductor substrate and the semiconductor substrate can be reduced. Corresponding to the second conductivity type of the first amorphous semiconductor region and the second amorphous semiconductor region among the carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate Carriers to be collected can be collected with higher efficiency by the first amorphous semiconductor region and the second amorphous semiconductor region. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

According to the method of manufacturing a photoelectric conversion element of the embodiment disclosed herein, a tunnel dielectric layer is formed on a second surface of a semiconductor substrate, and a second amorphous semiconductor layer is formed on the tunnel dielectric layer. Forming a second amorphous semiconductor region in the second amorphous semiconductor layer by doping a part of the second amorphous semiconductor layer with a second impurity. May be provided. In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the second surface of the semiconductor substrate is covered with the tunnel dielectric layer before the second amorphous semiconductor layer is formed. When the second amorphous semiconductor region is formed by doping the second amorphous semiconductor layer with a second impurity having the second conductivity type in part of the second amorphous semiconductor layer, the semiconductor substrate is doped with the second impurity. The tunnel dielectric layer can be reliably prevented. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, the semiconductor substrate can be reliably prevented from being doped with the second impurity in the second amorphous semiconductor region. According to the method for manufacturing the photoelectric conversion element of the embodiment disclosed herein, the second amorphous semiconductor layer and the tunnel dielectric layer between the semiconductor substrate and the first amorphous semiconductor layer are interposed. The heterojunction structure and the heterojunction structure between the semiconductor substrate and the first amorphous semiconductor region and the second amorphous semiconductor region via the tunnel dielectric layer can be reliably maintained. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured.

(34) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, a part of the first amorphous semiconductor layer and a part of the second amorphous semiconductor layer are doped with the second impurity. Doing may include implanting a second impurity into part of the first amorphous semiconductor layer and part of the second amorphous semiconductor layer. In one step of irradiating the ion beam of the second impurity, a part of the first amorphous semiconductor layer and a part of the second amorphous semiconductor layer may be doped with the second impurity. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(35) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, a second impurity is doped into a part of the first amorphous semiconductor layer and a part of the second amorphous semiconductor layer. Forming a dopant-containing film containing a second impurity on the first amorphous semiconductor layer; and adding the second impurity contained in the dopant-containing film to one of the first amorphous semiconductor layers. And transition to part of the second amorphous semiconductor layer. The first amorphous semiconductor is formed in one step of transferring the second impurity contained in the dopant-containing film to a part of the first amorphous semiconductor layer and a part of the second amorphous semiconductor layer. A part of the layer and a part of the second amorphous semiconductor layer may be doped with the second impurity. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(36) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, forming the dopant-containing film containing the second impurity on the first amorphous semiconductor layer is the first amorphous The doping paste containing the second impurity may be applied on a part of the crystalline semiconductor layer. Transferring the second impurity contained in the dopant-containing film to part of the first amorphous semiconductor layer and part of the second amorphous semiconductor layer may include heat-treating the doping paste. . In one step of heat-treating the dopant-containing film (doping paste), the second impurity can be doped into a part of the first amorphous semiconductor layer and a part of the second amorphous semiconductor layer. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(37) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the second impurity contained in the dopant-containing film may be a part of the first amorphous semiconductor layer and the second amorphous semiconductor. Transferring to a part of the layer may include irradiating a part of the dopant-containing film with laser light. In one step of irradiating a part of the dopant-containing film with laser light, a part of the first amorphous semiconductor layer and a part of the second amorphous semiconductor layer can be doped with the second impurity. . According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having improved characteristics and reliability can be manufactured by a simple process.

(38) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, forming the tunnel dielectric layer on the second surface of the semiconductor substrate may include forming the second surface of the semiconductor substrate with ozone water or It may include soaking in hydrogen peroxide solution. According to the method of manufacturing a photoelectric conversion element of the embodiment disclosed herein, the tunnel dielectric layer is quickly formed by a simple process of immersing the second surface of the semiconductor substrate in ozone water or hydrogen peroxide water. can do.

(39) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, forming the tunnel dielectric layer on the second surface of the semiconductor substrate thermally oxidizes the second surface of the semiconductor substrate. You may include that. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, the tunnel dielectric layer can be formed by a simple process of thermally oxidizing the second surface of the semiconductor substrate.

(40) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, forming the tunnel dielectric layer on the second surface of the semiconductor substrate includes forming a tunnel dielectric on the second surface of the semiconductor substrate. It may include depositing a body layer. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, the tunnel dielectric layer can be formed by a simple process of depositing the tunnel dielectric layer on the second surface of the semiconductor substrate.

(41) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the tunnel dielectric layer may have a thickness of 0.2 nm to 5.0 nm. The tunnel dielectric layer having a thickness of 0.2 nm or more can further improve the passivation characteristics of the photoelectric conversion element. The tunnel dielectric layer having a thickness of 5.0 nm or less allows carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate to be converted into the first amorphous semiconductor layer and the first amorphous semiconductor layer. Tunneling to the amorphous semiconductor region can be performed more efficiently. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate can be collected more efficiently. A photoelectric conversion element can be manufactured.

(42) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the first electrode electrically connected to the first amorphous semiconductor layer is provided on the second surface of the semiconductor substrate. It may further include forming and forming a second electrode electrically connected to the first amorphous semiconductor region on the second surface of the semiconductor substrate. According to the method of manufacturing a photoelectric conversion element of the embodiment disclosed herein, the first electrode and the second electrode are not provided on the first surface side of the semiconductor substrate which is the light incident surface. An element can be manufactured. Light incident on the photoelectric conversion element is not blocked by the first electrode and the second electrode. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element having a high short-circuit current _JSC and improved efficiency in converting light energy into electric energy can be manufactured.

(43) The method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein may further include forming a dielectric layer on the first surface of the semiconductor substrate. When the dielectric layer functions as an antireflection film, the dielectric layer can allow more light to enter the photoelectric conversion element. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured. When the dielectric layer functions as a passivation film, the dielectric layer is such that carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate are recombined on the first surface of the semiconductor substrate. Can be suppressed. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

(44) The method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein further includes forming a third amorphous semiconductor layer having i-type on the first surface of the semiconductor substrate. Also good. The third amorphous semiconductor layer having i-type suppresses recombination of carriers generated in the semiconductor substrate by light incident from the first surface side of the semiconductor substrate on the first surface of the semiconductor substrate. can do. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved passivation characteristics and efficiency of converting light energy into electric energy can be manufactured.

(45) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, a fourth amorphous semiconductor layer having the same conductivity type as the semiconductor substrate is formed on the first surface of the semiconductor substrate. May be further provided. The fourth amorphous semiconductor layer having the same conductivity type as that of the semiconductor substrate has a carrier that is close to the first surface of the semiconductor substrate among carriers generated in the semiconductor substrate when light is incident on the photoelectric conversion element. It can be pushed back into the substrate. The fourth amorphous semiconductor layer can suppress recombination of the carriers on the first surface of the semiconductor substrate. According to the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved passivation characteristics and efficiency of converting light energy into electric energy can be manufactured.

(46) The method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein may further include forming a concavo-convex structure on the first surface of the semiconductor substrate. By forming a concavo-convex structure on the first surface of the semiconductor substrate, which is the light incident surface, more light can be incident on the photoelectric conversion element. According to the photoelectric conversion element manufacturing method of the photoelectric conversion element of the embodiment disclosed herein, a photoelectric conversion element with improved efficiency of converting light energy into electric energy can be manufactured.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1, 4, 7 photoelectric conversion element, 11 semiconductor substrate, 11a first surface, 11b second surface, 12 third amorphous semiconductor layer, 13th fourth amorphous semiconductor layer, 14 dielectric layer, 15 second amorphous semiconductor layer, 16 first amorphous semiconductor region, 17 first amorphous semiconductor layer, 18 second electrode, 19 first electrode, 21 ion beam, 22 mask, 26 Dopant-containing film, 27 laser light, 46 second amorphous semiconductor region.

Claims

A semiconductor substrate having a first surface and a second surface opposite to the first surface;
A first amorphous semiconductor layer provided on the second surface and having a first conductivity type;
A first amorphous semiconductor region provided on the second surface and having a second conductivity type different from the first conductivity type;
The first amorphous semiconductor layer includes a first impurity having the first conductivity type;
The first amorphous semiconductor region includes the first impurity and a second impurity having the second conductivity type;
The photoelectric conversion element in which the first amorphous semiconductor layer and the first amorphous semiconductor region constitute one layer extending continuously.
The photoelectric conversion element according to claim 1, wherein the first amorphous semiconductor region exists over the entire thickness of the first amorphous semiconductor layer.
The photoelectric conversion element according to claim 1, wherein the first amorphous semiconductor layer is in direct contact with the second surface of the semiconductor substrate.
An i-type is formed between the first amorphous semiconductor layer and the second surface of the semiconductor substrate and between the first amorphous semiconductor region and the second surface of the semiconductor substrate. The photoelectric conversion element of Claim 1 or Claim 2 further provided with the 2nd amorphous semiconductor layer which has.
A semiconductor substrate having a first surface and a second surface opposite to the first surface;
A tunnel dielectric layer provided on the second surface;
A first amorphous semiconductor layer provided on the tunnel dielectric layer and having a first conductivity type;
A first amorphous semiconductor region provided on the tunnel dielectric layer and having a second conductivity type different from the first conductivity type;
The first amorphous semiconductor layer includes a first impurity having the first conductivity type;
The first amorphous semiconductor region includes the first impurity and a second impurity having the second conductivity type;
The photoelectric conversion element in which the first amorphous semiconductor layer and the first amorphous semiconductor region constitute one layer extending continuously.
The photoelectric conversion element according to claim 5, wherein the first amorphous semiconductor region exists over the entire thickness of the first amorphous semiconductor layer.
The photoelectric conversion element according to claim 5 or 6, wherein the first amorphous semiconductor layer is in direct contact with the tunnel dielectric layer.
A second amorphous semiconductor having i-type between the first amorphous semiconductor layer and the tunnel dielectric layer and between the first amorphous semiconductor region and the tunnel dielectric layer. The photoelectric conversion element according to claim 5, further comprising a layer.
A second amorphous semiconductor region provided in the second amorphous semiconductor layer and having the second conductivity type;
The second amorphous semiconductor region includes the second impurity;
The photoelectric conversion element according to claim 4, wherein the second amorphous semiconductor region is in contact with the first amorphous semiconductor region.
A first electrode provided on the second surface of the semiconductor substrate and electrically connected to the first amorphous semiconductor layer;
10. The semiconductor device according to claim 1, further comprising a second electrode provided on the second surface of the semiconductor substrate and electrically connected to the first amorphous semiconductor region. Item 1. The photoelectric conversion element according to item 1.
The photoelectric conversion element according to any one of claims 1 to 10, further comprising a dielectric layer on the first surface of the semiconductor substrate.
A first amorphous semiconductor layer having a first conductivity type is formed on the second surface of a semiconductor substrate having a first surface and a second surface opposite to the first surface. The first amorphous semiconductor layer includes a first impurity having the first conductivity type;
Forming a first amorphous semiconductor region having a second conductivity type in the first amorphous semiconductor layer,
Forming the first amorphous semiconductor region in the first amorphous semiconductor layer may include forming the first amorphous semiconductor layer in a part of the first amorphous semiconductor layer different from the first conductivity type. A method for manufacturing a photoelectric conversion element, comprising doping a second impurity having a conductivity type of 2.
Forming a tunnel dielectric layer on the second surface of the semiconductor substrate having a first surface and a second surface opposite the first surface;
Forming a first amorphous semiconductor layer having a first conductivity type on the tunnel dielectric layer, wherein the first amorphous semiconductor layer has a first conductivity type. 1 impurity,
Forming a first amorphous semiconductor region having a second conductivity type in the first amorphous semiconductor layer,
Forming the first amorphous semiconductor region in the first amorphous semiconductor layer may include forming the first amorphous semiconductor layer in a part of the first amorphous semiconductor layer different from the first conductivity type. A method for manufacturing a photoelectric conversion element, comprising doping a second impurity having a conductivity type of 2.