JPH07297444A - Photoelectric conversion device and its manufacture - Google Patents

Abstract

PURPOSE:To provide a photodiode which can obtain a large output current with a small area. CONSTITUTION:A second N-type conductive area 6 having a P-type conductivity section 6 is formed on a P-type semiconductor substrate 2. On this second conductivity section 6, a P-type bite-in section 4 is provided. The bite-in section 4 forms upper and lower P-N junction surfaces 11 and 12 almost parallel to the surface of the substrate 2 in the area 1. Therefore, more P-N junction surfaces can be obtained in the same planar extent and, as a result, a photoelectric conversion device having a large output current can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoelectric conversion device, and more particularly to an increase in output current.

[0002]

2. Description of the Related Art As shown in FIG. 7, a photodiode 51 has an N-type region 53 formed in a P-type semiconductor substrate 2 so as to form a PN bond. When the surface of the photodiode 51 is irradiated with light, holes and electron pairs are generated in the depletion layer on the PN coupling surface, and an output current flows from the cathode (K) to the anode (A).

Since the magnitude of this output current is proportional to the area of the PN junction, it is necessary to increase the area of the N-type region 53 in order to obtain a large output current. However, increasing the area of the N-type region 53 in this way results in a large photodiode as a whole.

Such a problem is caused by the phototransistor,
It occurs in all photoelectric conversion devices such as photo ICs and solar cells.

An object of the present invention is to solve the above problems and to provide a photoelectric conversion device capable of obtaining a large output current in a small area.

[0006]

According to a first aspect of the photoelectric conversion device of the present invention, a semiconductor substrate having a first conductivity type region and a second conductivity type region of the second conductivity type formed in the first conductivity type region. A first conductive type biting part provided so as to bite into the second conductive type region, the second conductive type having the following bite part connected to the first conductive type region. Between the region and the region, there is provided a biting portion in which a PN junction surface substantially parallel to the surface of the semiconductor substrate is formed vertically.

According to another aspect of the photoelectric conversion device of the present invention, the surface of the second conductivity type region has a surface region of the first conductivity type connected to the first conductivity type region, and the second conductivity type region is provided. A double diffusion transistor having a base layer having a depth substantially the same as that of the surface region is provided adjacent to the mold region in an insulating state.

In the method for manufacturing a photoelectric conversion device according to claim 3, A) the first lower layer of the first conductivity type is formed on a part of the surface of the first conductivity type area in the semiconductor substrate having the first conductivity type area. A lower seed portion forming step of forming a seed portion and a second lower seed portion, B) a second conductivity type on the first lower seed portion, the second lower seed portion and the first conductivity type region. A first epitaxial growth step of growing a first epitaxial layer of C), the step of forming the following c1) second middle part and c2) intermediate layer on the surface of the first epitaxial layer, c1) the second A second conductive seed portion of the first conductivity type located above the lower seed portion, c2) an intermediate layer located in a region in front of the second lower seed portion above the first lower seed portion, D) a second conductive layer on the second middle portion, the intermediate layer and the first epitaxial layer. A second epitaxial growth step of growing a second epitaxial layer of the mold, E) a step of forming the following e1) first upper seed portion and e2) second upper seed portion on the surface of the second epitaxial layer, e1 ) A first upper seed portion of the first conductivity type located above the first lower seed portion, e2) A second upper seed portion of the first conductivity type located above the second lower seed portion F) The element isolation region is formed by connecting the first lower seed portion and the first upper seed portion and connecting the second lower seed portion and the second upper seed portion. And a step of forming an element isolation region to be formed.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a photoelectric conversion device comprising: A) a semiconductor substrate having a first-conductivity-type region, a part of the surface of the first-conductivity-type region having a first conductivity type
A lower seed portion forming step of forming a third lower seed portion, B) growing a second conductivity type first epitaxial layer on the first to third lower seed portions and the first conductivity type region. A first epitaxial growth step, C) on the surface of the first epitaxial layer, c1) a second middle portion, c2) a third middle portion, c3) an intermediate layer, and c4)
Forming an intermediate connecting layer, c1) a second middle seed portion of the first conductivity type located above the second lower seed portion, c2) a first seed portion above the third lower seed portion A conductive type third middle seed portion, c3) an intermediate layer located in a region in front of the first lower seed portion to the second middle seed portion, c4) the second lower seed portion An intermediate connecting layer located above the region between the third lower seed portions, D) on the second to third middle seed portions, the intermediate layer, the intermediate connecting layer and the first epitaxial layer A second epitaxial growth step of growing a second conductive type second epitaxial layer, E) on the surface of the second epitaxial layer, e1) a first upper seed portion, e2) a second upper seed portion, e3 ) A third upper seed portion, and e4) a step of forming an upper connection portion, e1) a first upper seed portion of the first conductivity type located above the first lower seed portion, e2) The second upper seed portion of the first conductivity type located above the second lower seed portion, e3) the third upper seed portion of the first conductivity type located above the third lower seed portion, e4) an upper connecting portion of the first conductivity type located over substantially the same planar area as the intermediate connecting layer, F) connecting the lower seed portions to corresponding upper seed portions, and connecting the intermediate connecting layer to the intermediate seed layer An element isolation region forming step for forming an element isolation region by connecting to the upper connection part, G) the following g1) surface region and g2) a surface layer forming step for forming a base layer, g1) the first lower part The region defined by the seed portion and the second lower seed portion is used as the photoelectric conversion element forming portion, and the photoelectric conversion element forming portion is provided with the first portion above the intermediate layer to a depth that does not reach the intermediate layer. 2 a surface region of the first conductivity type located on the surface of the epitaxial layer so as to be connected to the first upper seed portion, g2) A region defined by the second lower seed portion and the third lower seed portion is used as the control element formation portion, and a base layer located at the same depth as the surface region in the control element formation portion. And H) an emitter region forming step of forming an emitter region in the base layer.

[0010]

In the photoelectric conversion device according to claim 1, the second
A first-conductivity-type bite portion that is provided so as to bite into the conductivity-type region, and a PN junction surface that is substantially parallel to the surface of the semiconductor substrate is formed vertically between the second-conductivity-type region and the second-conductivity-type region. It has a rubbing part. Therefore, more PN junction surfaces can be obtained in the same plane range. Thereby, a photoelectric conversion device with a large output current can be obtained.

According to another aspect of the photoelectric conversion device of the present invention, the surface of the second conductivity type region has a first conductivity type surface region connected to the first conductivity type region. Further, a double diffusion transistor having a base layer having substantially the same depth as the surface region is provided adjacent to the second conductivity type region in an insulating state. Therefore, the surface region can be formed in the process of manufacturing the base layer.

In the method for manufacturing a photoelectric conversion device according to a third aspect of the present invention, a first lower seed portion and a second lower seed portion of the first conductivity type are both formed on a part of the surface of the first conductivity type region. It
A second conductivity type first epitaxial layer is grown on this. Next, the second middle seed portion and the intermediate layer are formed on the surface of the first epitaxial layer. The second
By growing a second conductive type second epitaxial layer on the middle seed portion, the intermediate layer, and the first epitaxial layer, the first lower seed portion and the intermediate layer are connected. Further, the second lower seed portion and the second middle seed portion are connected.

The first upper seed portion and the second upper seed portion are formed on the surface of the second epitaxial layer, and the first lower seed portion and the first upper seed portion are connected to each other. With
An element isolation region is formed by connecting the second lower seed portion and the second upper seed portion. Further, the first upper seed portion and the intermediate layer are connected. That is, the first upper seed portion and the first lower seed portion are connected.

In this way, the second-conductivity-type regions adjacent to the first-conductivity-type regions substantially parallel to the surface of the semiconductor substrate are formed vertically. As a result, the area of the PN junction surface increases, so that a photoelectric conversion device with a large output current can be obtained.

In the method for manufacturing a photoelectric conversion device according to a fourth aspect of the present invention, first to third lower seed portions of the first conductivity type are formed on a part of the surface of the first conductivity type region, and the first seed type first to third seed portions are formed on the surface. Growing a first epitaxial layer of the second conductivity type. The second intermediate portion, the third intermediate portion, the intermediate layer, and the intermediate connection layer are formed on the surface of the first epitaxial layer.

By growing the second epitaxial layer thereon, the first lower seed portion and the intermediate layer are connected, and the second lower seed portion and the second middle seed portion are connected. Further, the second lower seed portion and the second middle seed portion are connected.

On the surface of the second epitaxial layer, the first upper seed portion, the second upper seed portion, the third upper seed portion,
And the element isolation region is formed by forming the upper connection portion and connecting each of the lower seed portions to the corresponding upper seed portion. Further, the first upper seed portion and the intermediate layer are connected. That is, the first upper seed portion and the first lower seed portion are connected. In this way, regions of the second conductivity type that are adjacent to the regions of the first conductivity type that are substantially parallel to the surface of the semiconductor substrate are formed vertically. As a result, the area of the PN junction surface increases, so that a photoelectric conversion device with a large output current can be obtained. Further, the control element formation portion is formed by connecting the intermediate connection layer and the upper connection portion.

A first conductivity type located in the photoelectric conversion element forming portion on the surface of the second epitaxial layer above the intermediate layer to a depth not reaching the intermediate layer so as to be connected to the first upper seed portion. A surface area is formed. In addition, a base layer is formed in the control element formation portion at the same depth as the surface region. Then, an emitter region is formed in the base layer.

In this way, the control element can be formed in the control element forming portion while forming the photoelectric conversion element in the photoelectric conversion element forming portion.

[0020]

【Example】

[Structure of Photodiode 1] An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a cross-sectional view of a main part of a photodiode 1 which is a photoelectric conversion device according to the present invention.

As shown in FIG. 1, the photodiode 1 has a second conductivity type region (N type) 6 formed in a P type semiconductor substrate 2 which is a first conductivity type region. Around the second conductivity type region 6, a P type low isolation L / I and an isolation ISO, which are element isolation regions, are formed.

The second conductivity type region 6 is provided with a P-type biting portion 4 in which PN junction surfaces 11 and 12 which are substantially parallel to the surface of the semiconductor substrate 2 are formed vertically. A P-type surface region 9 connected to the isolation ISO is formed on the surface of the semiconductor substrate 2 above the biting portion 4.

In this embodiment, the low isolation L / I, the isolation ISO, and the semiconductor substrate 2 constitute the first conductivity type region.

As described above, in the photodiode 1, the second conductivity type region 6 is provided with the P type biting portion 4, and the biting portion 4 allows the semiconductor to be formed in the second conductivity type region 6. PN junction surface 1 that is almost parallel to the surface of the substrate 2
1, 12 are formed on the upper and lower sides. Therefore, more PN junction surfaces can be obtained in the same plane range.
Thereby, a photoelectric conversion device with a large output current can be obtained. In addition, in this specification, the planar range means a range in a plane viewed from the surface of the semiconductor substrate.

In this photodiode 1, PN
Bonding surfaces 11 and 12 are formed. Therefore, about 5/3 times the current could be obtained in the same planar range as the conventional photodiode. The inventor considered the reason for obtaining a current of 5/3 times as follows. Conventional photodiodes have a total of 3 sides, one on the top and one on the side.
It has a surface PN junction. On the other hand, in the photodiode 1, one face is provided on each of the upper and lower sides, and one face is provided on the side faces.
There are more PN junction surfaces for a total of three surfaces. Therefore, a current of (3 + 3) / 3 times is calculated.
However, since the light transmission efficiency decreases as the distance from the surface increases, a current of 5/3 times is eventually obtained.

[Method of Manufacturing Photodiode 1] FIG.
A method of manufacturing the photodiode 1 will be described with reference to FIG. In this embodiment, the photodiode 1 is formed in the photoelectric conversion element forming portion, and the double diffusion transistor is formed in the control element forming portion.

As shown in FIG. 2A, a first lower seed portion 16 of the P type and a second lower seed portion of the P type are both formed on a part of the surface of the P type semiconductor substrate 2 of the first conductivity type by using a photoresist. Part 1
7 and the third lower seed portion 18 are formed by diffusion. In the present embodiment, the first lower seed portion 16 and the second lower seed portion 1
7 and the third lower seed portion 18 are connected to each other.

Next, the N type first epitaxial layer 21 is epitaxially grown from the state of FIG. 2A. As a result, as shown in FIG. 2B, on the first lower seed portion 16, the second lower seed portion 17, the third lower seed portion 18, and the P-type semiconductor substrate 2, the second conductivity type N is formed. Type first epitaxial layer 2
1 is deposited. At the same time, a P-type region grows in the first lower seed portion 16 to the third lower seed portion 18.

Next, a photoresist is used on the surface of the first epitaxial layer 21 to form a P-type second middle seed portion 27, a third middle seed portion 28, an intermediate layer 31, and an intermediate connection layer 32. Are formed by diffusion. As shown in FIG. 2C, the second middle seed portion 27 is formed above the second lower seed portion 17, and
The middle seed portion 28 is formed above the third lower seed portion 18. The intermediate layer 31 is formed in a region from above the first lower seed portion 17 to the second intermediate seed portion 18, and the intermediate connection layer 32 is formed in the second lower seed portion 17 and the third lower seed portion 17. It is formed above the region 19 between the seed portions 18. The intermediate layer 31
Constitute the biting part 4 of the photodiode 1 shown in FIG.

Next, the N type second epitaxial layer 22 is epitaxially grown from the state of FIG. 2C. As a result, as shown in FIG. 2D, the second epitaxial layer 22 is deposited on the second intermediate portion 17, the third intermediate portion 18, the intermediate layer 31, the intermediate connecting layer 32, and the first epitaxial layer. To be done. At the same time, the first lower seed portion 16 to the third lower seed portion 18, which are P-type regions, the second middle seed portion 17, the third middle seed portion 18, the intermediate layer 31, and the intermediate connecting layer 32. Also grows, so that the second lower seed portion 17 becomes the second middle seed portion 27.
The third lower seed portion 18 is connected to the third middle seed portion 28, and the intermediate layer 31 is connected to the first lower seed portion 16. In addition, the intermediate connection layer 32 includes the second intermediate seed portion 17 and the third intermediate seed portion 17.
Since it is formed above the region 19 between the intermediate seed portion 18 and the second intermediate seed portion 18, it is not connected to the second intermediate seed portion 17 and the third intermediate seed portion 18.

Next, a photoresist is used on the surface of the second epitaxial layer 22 to form a P-type first upper seed portion 36, a second upper seed portion 37, a third upper seed portion 38, and an upper seed portion 38. The connection portion 42 is formed by diffusion. As shown in FIG. 3A, the first upper seed portion 36 is formed above the first lower seed portion 16,
The second upper seed portion 37 is formed above the second lower seed portion 17, and the third upper seed portion 38 is formed above the third lower seed portion 18. Further, the upper connection portion 42 is formed over substantially the same planar range as the intermediate connection layer 32.

Next, heat treatment is performed. As a result, each lower seed portion and the corresponding upper seed portion are connected. Specifically, the first lower seed portion 16 and the first upper seed portion 36 are connected, the second lower seed portion 17 and the second upper seed portion 37 are connected, and the third lower seed portion 18 is connected. And the third upper seed portion 38 are connected to each other, and the element isolation region 4
4a-44c are formed. Also, by this heat treatment,
The intermediate connection layer 32 and the upper connection portion 42 are connected to each other to form a P-type collector region 34. In the manufacturing process shown in FIG. 3A, the first lower seed portion 16 is connected to the intermediate layer 31. Therefore, the intermediate layer 31 and the element isolation region 44a are connected.

Next, the N-type surface region 41 and the base layer 35 are formed by diffusion using a photoresist. Assuming that a region defined by the first lower seed portion 16 and the second lower seed portion 17 is a photoelectric conversion element forming portion Q1, the surface region 41 has the photoelectric conversion element forming portion as shown in FIG. 3C. It is formed on the second epitaxial layer surface 22 above the intermediate layer 31 at a depth not reaching the intermediate layer 31 in Q1. The surface region 41 is formed so as to be connected to the first upper seed portion 36. Also, the second lower seed portion 17 and the third lower seed portion 18
The base layer 35 is formed with the same depth as the surface region 41, with the region defined by and as the control element forming portion Q2.

Next, using a photoresist, as shown in FIG.
As shown in, the emitter region 36 is diffused and formed in the base layer 35. After that, a P ⁺ region 34a and an N ⁺ region 35a for contact are diffused and formed in the collector layer 34 and the base layer 35, respectively, using a photoresist.

Thus, in this embodiment, 2
The photodiode 1 can be formed in the manufacturing process of the heavy diffusion transistor Tr. That is, the biting part 4 of the photodiode 1 can be formed without requiring complicated steps.

In this manufacturing method, the various parts and the like are formed by diffusion using a photoresist, but they may be formed by ion implantation.

[Other Application Examples] FIG. 4 shows a photodiode having two bite portions 4 formed therein. In this example, a current about 7/3 times that of the conventional photodiode could be obtained. It should be noted that the manufacturing method may be performed by performing a plurality of steps of the corresponding portions in FIGS.

FIG. 5 shows an embodiment in which the photoelectric conversion device according to the present invention is applied to a phototransistor. As shown in FIG. 5, in the phototransistor 48, the P-type second conductivity type region 6 is formed in the N-type well region 46. Around the second conductivity type region 6, N type low isolation L / I and isolation ISO which are element isolation regions are formed. The second conductivity type region 6 is provided with the N-type bite part 4. By the biting portion 4, PN junction surfaces 11 and 12 that are substantially parallel to the surface of the semiconductor substrate 2 are vertically formed in the second conductivity type region 6.
An emitter region 47 is formed in the second conductivity type region 6.

FIG. 6 shows an embodiment in which the photoelectric conversion device according to the present invention is applied to a photo IC. As shown in FIG. 6, the photo IC 49 forms an N-type well region 34 in a P-type semiconductor substrate, and a P-type second region 34 is formed in the N-well region 34.
A conductivity type region 6 is formed. This N well region 34
Acts as a collector. An emitter 47 is formed in the P-type second conductivity type region 6. Since the biting part 4 is similar, description thereof will be omitted.

As described above, in the above-described embodiment (photodiode 1, phototransistor 46), the semiconductor substrate 2 is entirely formed of the first conductivity type region (P-type). A type well region may be formed and a photoelectric conversion device may be formed in this N type well region.

In the above embodiment, the bite portion is set to 1 or 2, but more may be provided.

In each of the above embodiments, the photoelectric conversion device according to the present invention is used as a photodiode, a phototransistor,
The case of application to a photo IC has been described, but it can also be applied to a solar cell.

The above embodiment (photodiode 1,
In the phototransistor 46), the first conductivity type is P
However, the first conductivity type may be N type and the second conductivity type may be P type, as shown in the photo IC 49 shown in FIG.

[0044]

In the photoelectric conversion device according to the first aspect of the present invention, the first-conductivity-type bite portion provided so as to bite into the second-conductivity-type region is provided between the second-conductivity-type region and the second-conductivity-type region. In addition, it has a biting part in which a PN junction surface substantially parallel to the surface of the semiconductor substrate is formed vertically. Therefore, more PN junction surfaces can be obtained in the same plane range. Accordingly, it is possible to provide a photoelectric conversion device that can obtain a large output current in a small area.

According to another aspect of the photoelectric conversion device of the present invention, the surface of the second conductivity type region has a first conductivity type surface region connected to the first conductivity type region. Further, a double diffusion transistor having a base layer having substantially the same depth as the surface region is provided adjacent to the second conductivity type region in an insulating state. Therefore, the surface region can be formed in the process of manufacturing the base layer. This allows
A photoelectric conversion device capable of obtaining a large output current in a small area can be provided without complicating the process.

In the method of manufacturing a photoelectric conversion device according to a third aspect of the present invention, a first lower seed portion and a second lower seed portion of the first conductivity type are both formed on a part of the surface of the first conductivity type region. It
A second conductivity type first epitaxial layer is grown on this. Next, the second middle seed portion and the intermediate layer are formed on the surface of the first epitaxial layer. The second
By growing a second conductive type second epitaxial layer on the middle seed portion, the intermediate layer, and the first epitaxial layer, the first lower seed portion and the intermediate layer are connected. Further, the second lower seed portion and the second middle seed portion are connected.

The first upper seed portion and the second upper seed portion are formed on the surface of the second epitaxial layer, and the first lower seed portion and the first upper seed portion are connected to each other. With
An element isolation region is formed by connecting the second lower seed portion and the second upper seed portion. Further, the first upper seed portion and the intermediate layer are connected. That is, the first upper seed portion and the first lower seed portion are connected.

In this way, the second conductivity type region adjacent to the first conductivity type region substantially parallel to the surface of the semiconductor substrate is vertically formed. This makes it possible to provide a manufacturing method capable of manufacturing a photoelectric conversion device capable of obtaining a large output current in a small area.

In the method for manufacturing a photoelectric conversion device according to a fourth aspect of the present invention, first to third lower seed portions of the first conductivity type are formed on a part of the surface of the first conductivity type region, and on the surface of the first conductivity type region, Growing a first epitaxial layer of the second conductivity type. The second intermediate portion, the third intermediate portion, the intermediate layer, and the intermediate connection layer are formed on the surface of the first epitaxial layer.

By growing the second epitaxial layer on this, the first lower seed portion and the intermediate layer are connected, and the second lower seed portion and the second middle seed portion are connected. Further, the second lower seed portion and the second middle seed portion are connected.

On the surface of the second epitaxial layer, the first upper seed portion, the second upper seed portion, the third upper seed portion,
And the element isolation region is formed by forming the upper connection portion and connecting each of the lower seed portions to the corresponding upper seed portion. Further, the first upper seed portion and the intermediate layer are connected. That is, the first upper seed portion and the first lower seed portion are connected. In this way, regions of the second conductivity type that are adjacent to the regions of the first conductivity type that are substantially parallel to the surface of the semiconductor substrate are formed vertically. As a result, the area of the PN junction surface increases, so that a photoelectric conversion device with a large output current can be obtained. Further, the control element formation portion is formed by connecting the intermediate connection layer and the upper connection portion.

A first conductivity type located in the photoelectric conversion element forming portion on the surface of the second epitaxial layer above the intermediate layer to a depth not reaching the intermediate layer so as to be connected to the first upper seed portion. A surface area is formed. In addition, a base layer is formed in the control element formation portion at the same depth as the surface region. Then, an emitter region is formed in the base layer.

In this way, the control element can be formed in the control element forming portion while forming the photoelectric conversion element in the photoelectric conversion element forming portion.

Therefore, it is possible to provide a manufacturing method capable of manufacturing a photoelectric conversion device capable of obtaining a large output current in a small area without complicating the process.

[Brief description of drawings]

FIG. 1 is a diagram showing a photodiode 1 according to the present invention.

FIG. 2 is a manufacturing process diagram of the photodiode 1.

FIG. 3 is a manufacturing process diagram of the photodiode 1.

FIG. 4 is a diagram showing a photodiode provided with two bite parts 4;

FIG. 5 is a diagram showing a phototransistor 48 according to the present invention.

FIG. 6 is a diagram showing a photo IC 49 according to the invention.

FIG. 7 is a diagram showing a conventional photodiode.

[Explanation of symbols]

 2 ... ・ Semiconductor substrate 4 ・ ・ ・ ・ ・ ・ Bite part 6 ・ ・ ・ ・ Second conductivity type region 11 ・ ・ ・ PN junction surface 12 ・ ・ ・ PN junction surface 16 ・····························································································································· <-> <-> epitaxial layers> 2nd middle part 28 ... 3rd middle part 31 ... Intermediate layer 32 ... Intermediate connection layer 35 ... Base layer 36. 1 upper seed part 37 ... 2nd upper seed part 38 ... 3rd upper seed part 41 ... Surface area Q1 ... Photoelectric conversion element formation part Q2. .... Control element forming section

Claims (4)

[Claims] 1. A) semiconductor substrate having a first conductivity type region, B) a second conductivity type region of a second conductivity type formed in the first conductivity type region, and C) a first conductivity type region. C1) a first conductivity type bite portion provided so as to bite into the second conductivity type region, and between the second conductivity type region, and A photoelectric conversion device, comprising: a biting portion in which PN junction surfaces that are substantially parallel to the surface of the semiconductor substrate are formed above and below. 2. The photoelectric conversion device according to claim 1, wherein a surface region of the second conductivity type region has a surface region of the first conductivity type connected to the first conductivity type region, A photoelectric conversion device comprising a double diffusion transistor having a base layer having a depth substantially the same as that of the surface region and being adjacent to the conductivity type region in an insulated state. 3. A) A first lower seed portion and a second lower seed portion of the first conductivity type are both formed on a part of the surface of the first conductivity type area in the semiconductor substrate having the first conductivity type area. B) a first epitaxial growth for growing a second conductive type first epitaxial layer on the first lower seed portion, the second lower seed portion and the first conductive type region. Step C) forming the following c1) second middle seed portion and c2) intermediate layer on the surface of the first epitaxial layer, c1) first conductive material located above the second lower seed portion. A second middle seed portion of the mold, c2) an intermediate layer located in a region in front of the first lower seed portion to the second middle seed portion, D) the second middle seed portion, the A second epitaxial layer of the second conductivity type is grown on the intermediate layer and the first epitaxial layer. And a step of forming the following e1) first upper seed portion and e2) second upper seed portion on the surface of the second epitaxial layer, e1) above the first lower seed portion. A first upper seed portion of the first conductivity type located at, e2) a second upper seed portion of the first conductivity type located above the second lower seed portion, and F) the first lower seed portion. And an element isolation region forming step of forming an element isolation region by connecting the first upper seed portion with the second lower seed portion and the second lower seed portion with each other. A method for manufacturing a photoelectric conversion device, comprising: 4. A method of manufacturing a photoelectric conversion device having a photoelectric conversion element forming portion and a control element forming portion, comprising: A) a part of the surface of the first conductive type region in a semiconductor substrate having a first conductive type region, First to first conductivity type
A lower seed portion forming step of forming a third lower seed portion, B) growing a second conductivity type first epitaxial layer on the first to third lower seed portions and the first conductivity type region. A first epitaxial growth step, C) on the surface of the first epitaxial layer, c1) a second middle portion, c2) a third middle portion, c3) an intermediate layer, and c4)
Forming an intermediate connecting layer, c1) a second middle seed portion of the first conductivity type located above the second lower seed portion, c2) a first seed portion above the third lower seed portion A conductive type third middle seed portion, c3) an intermediate layer located in a region in front of the first lower seed portion to the second middle seed portion, c4) the second lower seed portion An intermediate connecting layer located above the region between the third lower seed portions, D) on the second to third middle seed portions, the intermediate layer, the intermediate connecting layer and the first epitaxial layer A second epitaxial growth step of growing a second conductive type second epitaxial layer, E) on the surface of the second epitaxial layer, e1) a first upper seed portion, e2) a second upper seed portion, e3 ) A third upper seed portion, and e4) a step of forming an upper connection portion, e1) a first upper seed portion of the first conductivity type located above the first lower seed portion, e2) The second upper seed portion of the first conductivity type located above the second lower seed portion, e3) the third upper seed portion of the first conductivity type located above the third lower seed portion, e4) an upper connecting portion of the first conductivity type located over substantially the same planar area as the intermediate connecting layer, F) connecting the lower seed portions to corresponding upper seed portions, and connecting the intermediate connecting layer to the intermediate seed layer An element isolation region forming step for forming an element isolation region by connecting to the upper connection part, G) the following g1) surface region and g2) a surface layer forming step for forming a base layer, g1) the first lower part The region defined by the seed portion and the second lower seed portion is used as the photoelectric conversion element forming portion, and the photoelectric conversion element forming portion is provided with the first portion above the intermediate layer to a depth that does not reach the intermediate layer. 2 a surface region of the first conductivity type located on the surface of the epitaxial layer so as to be connected to the first upper seed portion, g2) A region defined by the second lower seed portion and the third lower seed portion is used as the control element formation portion, and a base layer located at the same depth as the surface region in the control element formation portion. And H) an emitter region forming step of forming an emitter region in the base layer, the method of manufacturing a photoelectric conversion device.