JP2016143721A - Photoelectric conversion element and method for manufacturing photoelectric conversion element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a constitution capable of increasing a current collection amount.SOLUTION: A photoelectric conversion element includes: a first conductivity type semiconductor substrate 1; and a first conductivity type amorphous semiconductor film 3 and a second conductivity type amorphous semiconductor film 5 on the semiconductor substrate 1. The first conductivity type amorphous semiconductor film 3 is electrically connected to the semiconductor substrate 1 at a plurality of openings 9 provided to the second conductivity type amorphous semiconductor film 5 with a space therebetween.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a photoelectric conversion element and a method for manufacturing the photoelectric conversion element.

  In recent years, a solar cell that directly converts solar energy into electric energy has been rapidly expected as a next-generation energy source particularly from the viewpoint of global environmental problems. Of these, the most manufactured and sold solar cells have a structure in which electrodes are formed on the light receiving surface on the side where sunlight enters and the back surface on the opposite side of the light receiving surface, respectively. is there.

  However, when an electrode is formed on the light receiving surface, sunlight is reflected and absorbed by the electrode, so that the amount of incident sunlight is reduced by the area of the electrode. Therefore, development of a back junction solar cell in which an electrode is formed only on the back surface is underway (see, for example, Patent Document 1).

  FIG. 19 is a schematic cross-sectional view of a back junction solar cell described in Patent Document 1. The back junction solar cell shown in FIG. 19 has a substantially intrinsic amorphous semiconductor 119, n-type amorphous silicon 120, and nitride on the light-receiving surface of a substrate 111 made of an n-type single crystal silicon wafer. A protective film 124 such as silicon is sequentially stacked.

  In the n region 122 corresponding to the n-type electrode 116 on the back surface of the substrate 111, a substantially intrinsic amorphous semiconductor layer 112, an n-type amorphous semiconductor layer 114, a silicon nitride layer 121, and N-type electrodes 116 are sequentially stacked. Further, the n-type amorphous semiconductor layer 114 and the n-type electrode 116 are connected through a hole penetrating the silicon nitride layer 121.

  In p region 123 corresponding to p-type electrode 117 on the back surface of substrate 111, substantially intrinsic amorphous semiconductor layer 113, p-type amorphous semiconductor layer 115, and p-type electrode 117 are formed on substrate 111. They are sequentially stacked.

  The n-type electrode 116 and the p-type electrode 117 are formed by providing copper layers 116b and 117b by plating on the base electrodes 116a and 117a formed by sputtering or the like, respectively.

  FIG. 20 shows a schematic plan view of the back surface of the back junction solar cell shown in FIG. As shown in FIG. 20, the n-type electrode 116 and the p-type electrode 117 are each formed in a comb shape so as to substantially cover the entire back surface of the substrate 111 with a predetermined interval therebetween.

International Publication No. 2013/027591

  However, conventionally, there has been a demand for further increasing the current collection amount of the back junction solar cell described in Patent Document 1.

  The embodiment disclosed herein includes a first conductivity type semiconductor substrate, a first conductivity type amorphous semiconductor film on the semiconductor substrate, and a second conductivity type amorphous semiconductor film. In the photoelectric conversion element, the first conductive amorphous semiconductor film is electrically connected to the semiconductor substrate in a plurality of openings provided in the crystalline semiconductor film at intervals.

  The embodiment disclosed herein includes a step of forming a second conductive type amorphous semiconductor film on a first conductive type semiconductor substrate and a second conductive type amorphous semiconductor film spaced apart from each other. A step of forming a plurality of openings, and a step of forming a second conductivity type amorphous semiconductor film and a first conductivity type amorphous semiconductor film in the plurality of openings, the first conductivity type amorphous In the step of forming a semiconductor film, the first conductive amorphous semiconductor film is a method for manufacturing a photoelectric conversion element that is electrically connected to a semiconductor substrate.

  According to the embodiment disclosed herein, it is possible to provide a configuration capable of increasing the amount of current collection as compared with the back junction solar cell described in Patent Document 1.

3 is a schematic enlarged plan view of an end portion on the back surface of the heterojunction back contact cell of Embodiment 1. FIG. It is typical sectional drawing in alignment with II-II of FIG. It is typical sectional drawing in alignment with III-III of FIG. 6 is a schematic cross-sectional view illustrating a part of the manufacturing process of the example of the method for manufacturing the heterojunction back contact cell of Embodiment 1. FIG. 6 is a schematic cross-sectional view illustrating a part of the manufacturing process of the example of the method for manufacturing the heterojunction back contact cell of Embodiment 1. FIG. 6 is a schematic cross-sectional view illustrating a part of the manufacturing process of the example of the method for manufacturing the heterojunction back contact cell of Embodiment 1. FIG. 6 is a schematic cross-sectional view illustrating a part of the manufacturing process of the example of the method for manufacturing the heterojunction back contact cell of Embodiment 1. FIG. 6 is a schematic cross-sectional view illustrating a part of the manufacturing process of the example of the method for manufacturing the heterojunction back contact cell of Embodiment 1. FIG. 6 is a schematic cross-sectional view illustrating a part of the manufacturing process of the example of the method for manufacturing the heterojunction back contact cell of Embodiment 1. FIG. 6 is a schematic enlarged plan view of the back surface of the heterojunction back contact cell of Embodiment 2. FIG. It is typical sectional drawing in alignment with XI-XI of FIG. It is typical sectional drawing in alignment with XII-XII of FIG. 6 is a schematic enlarged plan view of the back surface of a heterojunction back contact cell of Embodiment 3. FIG. It is typical sectional drawing in alignment with XIV-XIV of FIG. It is typical sectional drawing along XV-XV of FIG. 6 is a schematic enlarged plan view of the back surface of a heterojunction back contact cell of Embodiment 4. FIG. It is typical sectional drawing in alignment with XVII-XVII of FIG. It is typical sectional drawing in alignment with XVIII-XVIII of FIG. 2 is a schematic cross-sectional view of a back junction solar cell described in Patent Document 1. FIG. FIG. 20 is a schematic plan view of the back surface of the back junction solar cell shown in FIG. 19.

  Hereinafter, the heterojunction type back contact cell of Embodiments 1-4 as an example of the photoelectric conversion element of embodiment disclosed here is demonstrated. In the drawings used to describe the embodiments, the same reference numerals represent the same or corresponding parts.

[Embodiment 1]
<Structure of heterojunction back contact cell>
FIG. 1 is a schematic enlarged plan view of the end portion on the back surface of the heterojunction back contact cell of the first embodiment. In a plan view shown in FIG. 1, a linear first conductive amorphous semiconductor film 5 extending in the first direction 31 and a second linear conductive amorphous extending in the first direction 31. The semiconductor films 3 are alternately arranged in the second direction 32.

  In this embodiment, the first conductivity type semiconductor substrate 1 is an n-type single crystal silicon substrate, the first conductivity type amorphous semiconductor film 5 is an n type amorphous silicon film, and the second conductivity type amorphous silicon. The quality semiconductor film 3 is a p-type amorphous silicon film. In the present embodiment, the first direction 31 and the second direction 32 form an angle of 90 °, but the angle formed by the first direction 31 and the second direction 32 is not limited to 90 °.

  A first electrode 8 is located on the first conductive type amorphous semiconductor film 5, and a second electrode 7 is located on the second conductive type amorphous semiconductor film 3. The first electrode 8 is provided in a line extending in the extending direction (first direction 31) of the first conductive type amorphous semiconductor film 5, and the second electrode 7 is also provided in the second conductive type amorphous semiconductor. The film 3 is provided in a line extending in the extending direction of the film 3 (first direction 31).

  In the second conductive type amorphous semiconductor film 3, a plurality of dot-like openings 9 are arranged at intervals in the first direction 31, and a plurality of dot-like openings 9 arranged in the first direction 31 are arranged. Are arranged in the second direction 32 at intervals.

  In the present embodiment, each of the plurality of dot-like openings 9 has a circular shape in plan view, and the length D of each opening 9 in the second direction 32 is from the viewpoint of increasing the current collection amount. Is preferably 200 μm or more and 1000 μm or less. In addition, the gap G in the first direction 31 between two openings 9 adjacent in the first direction 31 is preferably 50 μm or more and 2000 μm or less from the viewpoint of increasing the current collection amount.

  FIG. 2 schematically shows a cross section taken along line II-II in FIG. FIG. 2 is a cross-sectional view of a portion including the opening 9 of the heterojunction back contact cell of the first embodiment. As shown in FIG. 2, the semiconductor substrate 1 includes a first surface 1 a serving as a light receiving surface and a second surface 1 b serving as a back surface opposite to the light receiving surface. On the second surface 1b of the semiconductor substrate 1, the first conductivity type regions 51 and the second conductivity type regions 52 are alternately arranged. The first conductivity type region 51 is a stacked body of the first i-type amorphous semiconductor film 4 and the first conductivity type amorphous semiconductor film 5. The second conductivity type region 52 is a stacked body of the second i-type amorphous semiconductor film 2 and the second conductivity type amorphous semiconductor film 3. In the present embodiment, each of the first i-type amorphous semiconductor film 4 and the second i-type amorphous semiconductor film 2 is an i-type amorphous silicon film.

  As shown in FIG. 2, in the first conductivity type region 51 located in the opening 9, the first i-type amorphous semiconductor film 4 is located on the second surface 1 b of the semiconductor substrate 1. The first conductive type amorphous semiconductor film 5 is located on the first i-type amorphous semiconductor film 4. Thereby, the first conductive type amorphous semiconductor film 5 is electrically connected to the semiconductor substrate 1 through the first i-type amorphous semiconductor film 4 in the opening 9.

  As shown in FIG. 2, in the second conductivity type region 52 surrounding the opening 9, the second i-type amorphous semiconductor film 2 is located on the second surface 1 b of the semiconductor substrate 1. The second conductive type amorphous semiconductor film 3 is located on the second i-type amorphous semiconductor film 2. In addition, the first conductivity type region 51 (the first i-type amorphous semiconductor film 4 and the first conductivity type region 51a) is formed on the peripheral edge portion 3a, which is the portion of the second conductivity type amorphous semiconductor film 3 located around the opening 9. The laminated body with the 1 conductive type amorphous semiconductor film 5 is located.

  The first electrode 8 is located on the first conductivity type amorphous semiconductor film 5. The second electrode 7 is located on the second conductivity type amorphous semiconductor film 3. The first electrode 8 and the second electrode 7 are located at an interval.

  FIG. 3 schematically shows a cross section taken along line III-III in FIG. FIG. 3 is a cross-sectional view of a portion not including the opening 9 of the heterojunction back contact cell of the first embodiment. In the location shown in FIG. 3, the first conductivity type region 51 is located on the second conductivity type region 52 between the two second electrodes 7 adjacent in the second direction 32. 3, the first i-type amorphous semiconductor film 4 is located between the second conductive type amorphous semiconductor film 3 and the first conductive type amorphous semiconductor film 5. Therefore, the second conductive type amorphous semiconductor film 3 and the first conductive type amorphous semiconductor film 5 can be electrically insulated.

In this embodiment, “i-type” means not only a completely intrinsic state 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 × (Less than 10 ¹⁵ / cm ³ ) is meant to include n-type or p-type impurities. In this embodiment, “n-type” means a state where the n-type impurity concentration is 1 × 10 ¹⁵ / cm ³ or more, and “p-type” means that the p-type impurity concentration is 1 × 10 ¹⁵ / cm ³ or more. Means the state. The n-type impurity concentration and the p-type impurity concentration can be measured by, for example, secondary ion mass spectrometry.

  In this embodiment, “amorphous silicon” includes not only amorphous silicon in which the dangling bonds of silicon atoms are not terminated with hydrogen, but also dangling bonds of silicon atoms such as hydrogenated amorphous silicon. In which is terminated with hydrogen.

<Method for manufacturing heterojunction back contact cell>
Hereinafter, an example of a method for manufacturing the heterojunction back contact cell of Embodiment 1 will be described with reference to schematic cross-sectional views of FIGS.

  First, as shown in FIG. 4, a first conductivity type semiconductor substrate 1 is prepared. As the first conductivity type semiconductor substrate 1, an n-type single crystal silicon substrate can be preferably used, but is not limited to an n-type single crystal silicon substrate, and for example, a conventionally known n-type semiconductor substrate may be used. it can.

  Next, as shown in FIG. 5, a second conductivity type region 52 is formed on the entire second surface 1 b of the semiconductor substrate 1. The formation method of the second conductivity type region 52 is not particularly limited. For example, the second i-type amorphous semiconductor film 2 is formed in contact with the second surface 1b of the semiconductor substrate 1 by plasma CVD, and then A method of forming the second conductive amorphous semiconductor film 3 in contact with the second i-type amorphous semiconductor film 2 can be used.

  As the second i-type amorphous semiconductor film 2, an i-type amorphous silicon film can be preferably used, but is not limited to an i-type amorphous silicon film. A crystalline semiconductor film can also be used.

  As the second conductive type amorphous semiconductor film 3, a p-type amorphous silicon film can be preferably used, but is not limited to a p-type amorphous silicon film. For example, a conventionally known p-type amorphous silicon film is used. A quality semiconductor film can also be used. For example, boron can be used as the p-type impurity.

  Next, as shown in FIG. 6, a part of the second conductivity type region 52, which is a laminate of the second i-type amorphous semiconductor film 2 and the second conductivity type amorphous semiconductor film 3, is thickened. By removing in the direction, a plurality of dot-shaped openings 9 are formed. In FIG. 6, only one opening 9 is shown for convenience of explanation.

  The method for forming the dot-shaped opening 9 is not particularly limited. For example, a photoresist having an opening at a position corresponding to the position where the dot-shaped opening 9 is formed is formed on the second conductive type amorphous semiconductor film 3. Then, using the photoresist as a mask, a method such as photo etching for etching the second conductivity type region 52 in the thickness direction can be used.

  Next, as shown in FIG. 7, the first conductivity type region 51 is formed so as to cover the second conductivity type region 52 after the formation of the plurality of dot-like openings 9. The method for forming the first conductivity type region 51 is not particularly limited. For example, the first conductivity type region 51 may be formed on the second surface 1b of the semiconductor substrate 1 and the second conductivity type region 52 exposed from the plurality of dot-shaped openings 9 by plasma CVD. A first i-type amorphous semiconductor film 4 is formed in contact with the first i-type amorphous semiconductor film 4, and then a first conductive amorphous semiconductor film 5 is formed in contact with the first i-type amorphous semiconductor film 4. be able to.

  As the first i-type amorphous semiconductor film 4, an i-type amorphous silicon film can be preferably used. However, the first i-type amorphous semiconductor film is not limited to the i-type amorphous silicon film, and for example, a conventionally known i-type non-crystalline film is used. A crystalline semiconductor film can also be used.

  As the first conductive type amorphous semiconductor film 5, an n-type amorphous silicon film can be preferably used, but is not limited to an n-type amorphous silicon film, and for example, a conventionally known n-type amorphous silicon film is used. A quality semiconductor film can also be used. For example, phosphorus can be used as the n-type impurity.

  Next, as shown in FIG. 8, the second conductive type amorphous semiconductor film 3 is exposed by removing a part of the first conductive type region 51 in the thickness direction. Although the removal method of the 1st conductivity type area | region 51 is not specifically limited, For example, methods, such as photoetching, can be used.

  Next, as shown in FIG. 9, the second electrode 7 is formed on the second conductive amorphous semiconductor film 3 and the first electrode 8 is formed on the first conductive amorphous semiconductor film 5. . Although the formation method of the 1st electrode 7 and the 2nd electrode 8 is not specifically limited, For example, it can form by a vapor deposition method etc.

  By the above method, the heterojunction back contact cell of Embodiment 1 can be manufactured.

<Mechanism of problem solving>
In the heterojunction back contact cell of Embodiment 1, the first conductive type amorphous semiconductor film 5 of the first conductive type region 51 is formed in the plurality of dot-like openings 9 provided in the second conductive type region 52. And the first conductive type semiconductor substrate 1 are electrically connected. Thereby, in Embodiment 1, the formation area of the 2nd conductivity type area | region 52 provided on the 2nd surface 1b of the semiconductor substrate 1 can be enlarged compared with patent document 1. FIG. Thereby, in the heterojunction back contact cell of Embodiment 1, compared with patent document 1, the formation area of the 2nd electrode 7 on the 2nd conductivity type area | region 52 can be enlarged, and by extension, patent document 1 It is possible to increase the current collection amount as compared with the described back junction solar cell.

  That is, in the heterojunction back contact cell of Embodiment 1 and the back junction solar cell described in Patent Document 1, a region of conductivity type opposite to that of the semiconductor substrate 1 and the substrate 111 (in this embodiment, a p-type region). ) Since current is taken out from the electrodes (second electrode 7 and p-type electrode 117) provided thereon, the larger the area where the electrodes can be formed, the larger the current collection amount. By increasing the formation area of the electrode from which current is extracted, the amount of current collected from the electrode can be increased.

  In the above description, the first conductivity type is n-type and the second conductivity type is p-type. However, even when the first conductivity type is p-type and the second conductivity type is n-type. The same effect as described above can be obtained.

[Embodiment 2]
FIG. 10 is a schematic enlarged plan view of the back surface of the heterojunction back contact cell according to the second embodiment. In the heterojunction back contact cell of Embodiment 2, the island-shaped first conductive amorphous semiconductor film 5 is provided inside each of the plurality of dot-shaped openings 9, and the first conductive amorphous silicon The island-shaped first electrode 8 is provided inside each surface of the crystalline semiconductor film 5.

  FIG. 11 schematically shows a cross section taken along the line XI-XI in FIG. FIG. 11 is a cross section of a portion including the opening 9 of the heterojunction back contact cell of the second embodiment. As shown in FIG. 11, inside the opening 9, a first conductivity type region 51, which is a stacked body of the first i-type amorphous semiconductor film 4 and the first conductivity type amorphous semiconductor film 5. And the first electrode 8 on the first conductivity type region 51 are disposed. In addition, outside the opening 9, a second conductivity type region 52 that is a laminate of the second i-type amorphous semiconductor film 2 and the second conductivity type amorphous semiconductor film 3, and a second conductivity type The second electrode 7 on the region 52 is disposed. The island-shaped first electrode 8 is disposed inside the surface of the first conductivity type amorphous semiconductor film 5.

  FIG. 12 schematically shows a cross section taken along the line XII-XII in FIG. FIG. 12 is a cross-sectional view of a portion not including the opening 9 of the heterojunction back contact cell of the second embodiment. In the location shown in FIG. 12, nothing is formed on the second conductive type amorphous semiconductor film 3 in the second conductive type region 52 between the two second electrodes 7 adjacent in the second direction 32. Absent.

  Since the description other than the above in the second embodiment is the same as that in the first embodiment, the description thereof will not be repeated.

[Embodiment 3]
FIG. 13 is a schematic enlarged plan view of the back surface of the heterojunction back contact cell according to the third embodiment. In the heterojunction back contact cell of Embodiment 3, the island-shaped first conductive amorphous semiconductor film 5 is provided inside each of the plurality of dot-shaped openings 9, and the island-shaped first conductive A linear first electrode 8 extending in the first direction 31 is provided so as to electrically connect a plurality of type amorphous semiconductor films 5. Further, in the heterojunction back contact cell of Embodiment 3, the side surface of the second electrode 7 extending in the first direction 31 has a recess 7a having a shape surrounding a part of each peripheral edge of the plurality of openings 9, It is also characterized in that convex portions 7b protruding toward the gap between two adjacent openings 9 are alternately provided.

  FIG. 14 schematically shows a cross section taken along XIV-XIV in FIG. FIG. 14 is a cross section of a portion including the opening 9 of the heterojunction back contact cell of the third embodiment. As shown in FIG. 14, inside the opening 9, a first conductivity type region 51, which is a stacked body of the first i-type amorphous semiconductor film 4 and the first conductivity type amorphous semiconductor film 5. And the first electrode 8 on the first conductivity type region 51 are disposed. In addition, outside the opening 9, a second conductivity type region 52 that is a laminate of the second i-type amorphous semiconductor film 2 and the second conductivity type amorphous semiconductor film 3, and a second conductivity type The second electrode 7 on the region 52 is disposed.

  FIG. 15 schematically shows a cross section taken along the line XV-XV in FIG. FIG. 15 is a cross-sectional view of a portion that does not include the opening 9 of the heterojunction back contact cell according to the third embodiment. 15, the insulating layer 10 is disposed on the second conductive type amorphous semiconductor film 3 in the second conductive type region 52 between the two second electrodes 7 adjacent to each other in the second direction 32. The first electrode 8 is disposed on the insulating layer 10. The insulating layer 10 is not particularly limited as long as it is a material that can electrically insulate the second conductive type amorphous semiconductor film 3 and the first electrode 8.

  In the third embodiment, the formation area of the second electrode 7 on the second conductive type amorphous semiconductor film 3 can be increased as compared with the first and second embodiments. Therefore, in the third embodiment, the current collection amount can be further increased as compared with the first and second embodiments.

  Since the description other than the above in Embodiment 3 is the same as that in Embodiments 1 and 2, the description thereof will not be repeated.

[Embodiment 4]
FIG. 16 is a schematic enlarged plan view of the back surface of the heterojunction back contact cell according to the fourth embodiment. In the heterojunction back contact cell of Embodiment 4, the island-shaped first conductive type amorphous semiconductor film 5 is provided inside each of the plurality of dot-shaped openings 9, and the first conductive type amorphous semiconductor is provided. The island-shaped first electrode 8 is provided inside each surface of the crystalline semiconductor film 5. Further, in the heterojunction back contact cell of Embodiment 4, the side surface of the second electrode 7 extending in the first direction 31 has a concave portion 7a having a shape surrounding a part of each peripheral edge of the plurality of openings 9, It is also characterized in that convex portions 7b protruding toward the gap between two adjacent openings 9 are alternately provided.

  FIG. 17 schematically shows a cross section taken along XVII-XVII in FIG. FIG. 17 is a cross section of a portion including the opening 9 of the heterojunction back contact cell of the fourth embodiment. As shown in FIG. 17, the first i-type amorphous semiconductor film 4, the first conductive type amorphous semiconductor film 5, and the inside of the opening 9 on the second surface 1 b of the semiconductor substrate 1 are provided. The first conductivity type region 51 that is a laminate of the first conductivity type and the first electrode 8 on the first conductivity type region 51 are disposed. In addition, outside the opening 9, a second conductivity type region 52 that is a laminate of the second i-type amorphous semiconductor film 2 and the second conductivity type amorphous semiconductor film 3, and a second conductivity type The second electrode 7 on the region 52 is disposed.

  FIG. 18 schematically shows a cross section taken along the line XVIII-XVIII in FIG. FIG. 18 is a cross section of a portion not including the opening 9. In the location shown in FIG. 18, the distance between two second electrodes 7 adjacent in the second direction 32 is further narrower than in the first to third embodiments.

  In the fourth embodiment, the formation area of the second electrode 7 on the second conductive amorphous semiconductor film 3 can be further increased as compared with the first to third embodiments. Therefore, in the fourth embodiment, the current collection amount can be further increased as compared with the first to third embodiments.

  Since descriptions other than the above in the fourth embodiment are the same as those in the first to third embodiments, the description thereof will not be repeated.

[Appendix]
(1) An embodiment disclosed herein includes a first conductivity type semiconductor substrate, a first conductivity type amorphous semiconductor film on the semiconductor substrate, and a second conductivity type amorphous semiconductor film. In the photoelectric conversion element, the first conductive amorphous semiconductor film is electrically connected to the semiconductor substrate in a plurality of openings provided in the conductive amorphous semiconductor film at intervals. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (2) In the photoelectric conversion element of the embodiment disclosed here, it is preferable that each of the plurality of openings has a dot shape. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (3) In the photoelectric conversion element of the embodiment disclosed herein, it is preferable that each of the plurality of openings has a circular shape in plan view. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (4) In the photoelectric conversion element of an embodiment indicated here, it is preferred that a plurality of openings are arranged in the 1st direction. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (5) In the photoelectric conversion element of the embodiment disclosed here, it is preferable that the row | line | column of the some opening part located in a line with the 1st direction is located in a 2nd direction different from a 1st direction. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (6) In the photoelectric conversion element of the embodiment disclosed herein, the length of each of the plurality of openings in the second direction is preferably 200 μm or more and 1000 μm or less. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (7) In the photoelectric conversion element of the embodiment disclosed herein, the interval in the first direction between two openings adjacent in the first direction is preferably 50 μm or more. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (8) In the photoelectric conversion element of the embodiment disclosed herein, the first conductive type amorphous semiconductor film is located in at least a part of the region other than the plurality of openings of the second conductive type amorphous semiconductor film. It is preferable to do. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (9) The photoelectric conversion element of the embodiment disclosed herein preferably further includes a first i-type amorphous semiconductor film between the semiconductor substrate and the first conductive amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (10) In the photoelectric conversion element of the embodiment disclosed herein, it is preferable that the first i-type amorphous semiconductor film is in contact with each of the semiconductor substrate and the first conductivity-type amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (11) In the photoelectric conversion element of the embodiment disclosed herein, the first i-type amorphous semiconductor film preferably contains i-type amorphous silicon. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (12) In the photoelectric conversion element of the embodiment disclosed herein, a part of the first i-type amorphous semiconductor film is a first conductive type amorphous semiconductor film and a second conductive type amorphous semiconductor film. It is preferable that it is located between. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (13) The photoelectric conversion element of the embodiment disclosed herein preferably further includes a second i-type amorphous semiconductor film between the semiconductor substrate and the second conductive amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (14) In the photoelectric conversion element of the embodiment disclosed herein, the second i-type amorphous semiconductor film is preferably in contact with each of the semiconductor substrate and the second conductivity-type amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (15) In the photoelectric conversion element of the embodiment disclosed herein, the second i-type amorphous semiconductor film preferably contains i-type amorphous silicon. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (16) In the photoelectric conversion element of the embodiment disclosed herein, a part of the first i-type amorphous semiconductor film is a first conductive type amorphous semiconductor film and a second conductive type amorphous semiconductor film. It is preferable to contact each of the above. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (17) The photoelectric conversion element of the embodiment disclosed herein preferably further includes a first electrode on the first conductive type amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (18) In the photoelectric conversion element of the embodiment disclosed herein, the first electrode is preferably in a line shape. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (19) In the photoelectric conversion element of the embodiment disclosed herein, the first electrode is preferably in an island shape. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (20) In the photoelectric conversion element of the embodiment disclosed herein, the first electrode is preferably circular in a plan view. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (21) It is preferable that the photoelectric conversion element of the embodiment disclosed herein further includes a second electrode on the second conductivity type amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (22) In the photoelectric conversion element of the embodiment disclosed herein, the second electrode is preferably in a line shape. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (23) In the photoelectric conversion element of the embodiment disclosed herein, a recess that surrounds a part of the periphery of each of the plurality of openings, and a protrusion that protrudes toward a gap between two adjacent openings, Are preferably provided alternately. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (24) In the photoelectric conversion element of the embodiment disclosed herein, it is preferable that the second electrode is disposed with a gap from the first electrode. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (25) In the photoelectric conversion element of the embodiment disclosed herein, the first conductive amorphous semiconductor film preferably contains the first conductive amorphous silicon. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (26) In the photoelectric conversion element of the embodiment disclosed herein, it is preferable that the second conductivity type amorphous semiconductor film includes second conductivity type amorphous silicon. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (27) In the photoelectric conversion element of the embodiment disclosed herein, it is preferable that the semiconductor substrate includes crystalline silicon of the first conductivity type. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (28) In the photoelectric conversion element of the embodiment disclosed herein, it is preferable that the first conductivity type is n-type and the second conductivity type is p-type. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (29) In the embodiment disclosed herein, a step of forming a second conductive type amorphous semiconductor film on a first conductive type semiconductor substrate and a second conductive type amorphous semiconductor film are spaced apart from each other. Forming a plurality of openings, and forming a first conductivity type amorphous semiconductor film in the plurality of openings and the first conductivity type amorphous semiconductor film. In the step of forming the porous semiconductor film, the first conductive amorphous semiconductor film is a method for manufacturing a photoelectric conversion element that is electrically connected to the semiconductor substrate. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (30) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the step of forming the second conductive type amorphous semiconductor film includes forming the second i type amorphous semiconductor film on the semiconductor substrate. And a step of forming a second conductivity type amorphous semiconductor film on the second i-type amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (31) In the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, the second i-type amorphous semiconductor film is formed in contact with the semiconductor substrate, and the second conductivity-type amorphous semiconductor film is the second It is preferably formed in contact with the i-type amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (32) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the second i-type amorphous semiconductor film preferably contains i-type amorphous silicon. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (33) In the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, it is preferable that the step of forming the plurality of openings includes a step of forming the plurality of openings in a dot shape. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (34) In the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, the step of forming the plurality of openings preferably includes a step of forming the plurality of openings in a circular shape in plan view. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (35) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the step of forming the plurality of openings includes a step of forming the plurality of openings by arranging the plurality of openings in the first direction. Is preferred. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (36) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the step of forming the plurality of openings includes a step in which the plurality of openings arranged in the first direction is different from the first direction. It is preferable to include a step of forming a plurality of openings so as to be aligned in two directions. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (37) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, in the step of forming the plurality of openings, the length of each of the plurality of openings in the second direction is 200 μm or more and 1000 μm or less. Preferably, the method includes a step of forming a plurality of openings. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (38) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the interval in the first direction between two openings adjacent in the first direction is preferably 50 μm or more. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (39) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the step of forming the plurality of openings includes a step of photoetching a part of the second conductivity type amorphous semiconductor film. preferable. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (40) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the step of forming the first conductive type amorphous semiconductor film includes the second conductive type amorphous after forming the plurality of openings. Forming a first i-type amorphous semiconductor film so as to cover the semiconductor film; and forming a first conductive amorphous semiconductor film on the first i-type amorphous semiconductor film. It is preferable. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (41) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the first i-type amorphous semiconductor film is in contact with the second conductive type amorphous semiconductor film and the semiconductor substrate in the plurality of openings. The first conductive type amorphous semiconductor film is preferably formed in contact with the first i-type amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (42) In the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, the first i-type amorphous semiconductor film preferably contains i-type amorphous silicon. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (43) A method of manufacturing a photoelectric conversion element according to an embodiment disclosed herein includes a step of removing a part of each of the first i-type amorphous semiconductor film and the first conductivity-type amorphous semiconductor film; Preferably, the method further includes a step of forming a second electrode on the second conductivity type amorphous semiconductor film after the removing step. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (44) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the step of forming the second electrode preferably includes a step of forming the second electrode in a line shape. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (45) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the step of forming the second electrode includes the step of forming a concave portion in which the side surface of the second electrode surrounds a part of the periphery of each of the plurality of openings. It is preferable to include a step of forming the second electrode so as to alternately include protrusions protruding toward the gap between two adjacent openings. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (46) It is preferable that the manufacturing method of the photoelectric conversion element of embodiment disclosed here further includes the process of forming a 1st electrode on a 1st conductivity type amorphous semiconductor film. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (47) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the step of forming the first electrode preferably includes a step of forming the first electrode in a line shape. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (48) In the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, the step of forming the first electrode preferably includes a step of forming the first electrode in an island shape. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (49) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the step of forming the second electrode preferably includes a step of forming the second electrode in a circular shape in plan view. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (50) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the first conductivity type amorphous semiconductor film preferably includes the first conductivity type amorphous silicon. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (51) In the method of manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the second conductivity type amorphous semiconductor film preferably includes second conductivity type amorphous silicon. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (52) In the method for manufacturing a photoelectric conversion element according to the embodiment disclosed herein, the semiconductor substrate preferably includes first conductivity type crystalline silicon. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  (53) In the method for manufacturing a photoelectric conversion element of the embodiment disclosed herein, it is preferable that the first conductivity type is n-type and the second conductivity type is p-type. In this case, the amount of current collection can be increased as compared with the back junction solar cell described in Patent Document 1.

  Although the embodiments of the present invention have been described above, it is also planned from the beginning to combine the configurations of the above-described embodiments as appropriate.

  It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. 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.

  Embodiment disclosed here can be utilized for the manufacturing method of a photoelectric conversion element and a photoelectric conversion element, and may be suitably used for the manufacturing method of a solar cell and a solar cell, Especially preferably, it is hetero. There is a possibility that it can be used in a manufacturing method of a junction type back contact cell and a hetero junction type back contact cell.

  DESCRIPTION OF SYMBOLS 1 Semiconductor substrate, 1a 1st surface, 1b 2nd surface, 2nd 2nd i-type amorphous semiconductor film, 3rd 2nd conductivity type amorphous semiconductor film, 3a peripheral part, 4th 1st i-type non- A crystalline semiconductor film, 5 first conductive type amorphous semiconductor film, 7 second electrode, 7a recess, 7b protrusion, 8 first electrode, 9 opening, 9a row, 10 insulating layer, 31 first direction, 32 Second direction, 51 First conductivity type region, 52 Second conductivity type region, 111 substrate, 112 n region, 113 p region, 114 n type amorphous semiconductor layer, 115 p type amorphous semiconductor layer, 116 n type Electrode, 116a base electrode, 116b copper layer, 117 p-type electrode, 117a base electrode, 117b copper layer, 119 substantially intrinsic amorphous semiconductor, 120 n-type amorphous silicon, 121 silicon nitride layer, 122 n region , 123p region, 124 protection .

Claims (5)

A first conductivity type semiconductor substrate;
A first conductive type amorphous semiconductor film and a second conductive type amorphous semiconductor film on the semiconductor substrate;
Photoelectric conversion in which the first conductive amorphous semiconductor film is electrically connected to the semiconductor substrate in a plurality of openings provided in the second conductive amorphous semiconductor film at intervals. element.   The photoelectric conversion element according to claim 1, wherein each of the plurality of openings has a dot shape.   The photoelectric conversion element according to claim 1, wherein the plurality of openings are arranged in the first direction.   4. The first conductive amorphous semiconductor film according to claim 1, wherein the first conductive amorphous semiconductor film is located in at least a part of a region other than the plurality of openings of the second conductive amorphous semiconductor film. 5. The photoelectric conversion element as described in 2. Forming a second conductive type amorphous semiconductor film on the first conductive type semiconductor substrate;
Forming a plurality of openings spaced apart from each other in the second conductive type amorphous semiconductor film;
Forming a second conductive type amorphous semiconductor film and a first conductive type amorphous semiconductor film in the plurality of openings,
The method of manufacturing a photoelectric conversion element, wherein in the step of forming the first conductive type amorphous semiconductor film, the first conductive type amorphous semiconductor film is electrically connected to the semiconductor substrate.

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