JPS60211882A - Photoelectric conversion device and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention The present invention provides a plurality of photoelectric conversion elements (also simply referred to as elements) in which a non-single crystal semiconductor including an amorphous semiconductor that generates photovoltaic force upon irradiation with light is provided on a substrate having an insulating surface. The present invention relates to a photoelectric conversion device that irradiates light from the second electrode side in a photoelectric conversion device that is electrically connected in series and generates a high voltage, and a method for manufacturing the same.

The arrangement, size, and shape of elements in the device of the present invention are determined by design specifications. However, in order to simplify the content of the present invention, in the following detailed description, the first electrode on the lower side (substrate side) of the first element and the second electrode on the right side of the first electrode will be described. The following description is based on the case where the two electrodes (semiconductor-H, ie, the side away from the substrate) are electrically connected in series.

In such a configuration, the third groove for separating the second electrodes of the first element and the second element from each other is in close contact with the P or N type non-single crystal semiconductor layer. A non-oxide translucent conductive film (hereinafter simply referred to as TCNO) made of a compound (mixture) with a metal, particularly chromium silicide, is provided, and a transparent conductive film containing tin oxide or indium oxide as the main component is provided on the conductive film. It is characterized in that it is configured as a conductor by laminating photoconductive films (hereinafter also simply referred to as TCO).

In the present invention, a second electrode conductor provided on a semiconductor is scribed using a laser beam to form separate electrodes. At that time, in order to prevent the non-single-crystalline semiconductor underneath, especially the hydrogenated amorphous semiconductor, from becoming polycrystalline and becoming conductive when irradiated with laser light at a high temperature of 1800 degrees Celsius, it has sublimation properties. , and a TCO with relatively low thermal conductivity, and a non-oxide translucent conductive film (TCNO) is laminated thereunder, and by applying LS to the laminated conductive film, the semiconductor under the third trench is formed. The semiconductor layer is maintained in its initial state without being removed, thereby preventing polycrystalization and microcrystalization due to laser annealing of the semiconductor in any of the open grooves.

That is, conventionally, ITO (
Electron beam evaporation of a transparent conductive oxide film containing indium oxide as the main component was used.

However, ITO continues to undergo oxidation reactions during long-term use of the underlying non-single crystal semiconductor, and a silicon oxide insulating film is formed as a barrier at the boundary. For these reasons, improvements in the second electrode have been desired.

In addition, for CTO-only electrodes, the third groove is
If you try to form the first electrode by scribing, it is easy to scribe and damage not only the semiconductor underneath, but also the first electrode below it. Until now, there was no known method for forming the second electrode using a maskless process.

For this purpose, the present invention utilizes a maskless process, that is, L
An intermetallic compound, which is a non-oxide transparent conductive film, is formed by the reaction between chromium and the semiconductor, which can create open grooves using S.
For example, chromium or chromium silicide is applied to a non-single crystal semiconductor to prevent interfacial reactions between semiconductor metals and damage to the semiconductor and its first electrode during LSO.
It was formed to a thickness of ~200 people. Another 100-300
℃Typically, heat treatment at a temperature of 200℃ (30 minutes to 5 hours) causes a reaction with the underlying silicon material, resulting in extremely thermally stable and dense ROM silicide (Cr
It has been experimentally found that an extremely stable buffer 1- can be constructed with a thickness of 30 to 200 layers. Furthermore, the resistance of the ohmic contact with the N- or P-type semiconductor layer was also low and highly desirable.

Further, the present invention provides a second electrode having a two-layer structure of TCNO and TCO, in which TCO is laminated to a thickness of 200 to 2,000 layers on the upper surface by the same electron beam evaporation method or sputtering method. That is, it is a great advantage that TCNO and TCO can be manufactured by the same electron beam evaporation method without using any extra steps in the manufacturing process.

The details of the invention are shown below in accordance with the drawings.

FIG. 1 is a longitudinal sectional view showing the manufacturing process of the present invention.

In the drawing, a substrate (1) with an insulating surface is, for example, a stainless steel plate (for example, thickness 20-100μ, e.g. 50μ, length [left-right direction in the drawing) 60cm, medium 20c+n><
16) was used. Further, a heat-resistant organic resin (17) such as a polyimide resin was formed on the entire upper surface of the substrate, and this was used as a substrate (1). Further, on these substrates having insulating surfaces, a 4% coating (14) containing chromium as the main component was formed by magnetron sputtering to a thickness of 100 mm. Furthermore, ITO is applied to the top surface to a thickness of 1050 mm (if the semiconductor on the top surface is N-type)
Alternatively, tin oxide (15) was formed to a thickness of 1050 nm (if the semiconductor thereon was P type).

After this, WAG laser processing machine (manufactured by Nippon Laser, wavelength 1.
06μ or 0.53μ) average output 0.1~3W
(focal length 40mm) by applying Q switch and opening
(13) was formed. This spot diameter is 20~70μ
The φ was typically controlled to 50 μφ by a microcomputer. Thus, by scanning the first electrode conductor with this irradiated laser beam, the first open groove (1
3) was formed, and the first electrode (2) was produced in each inter-element region (31), (11').

It goes without saying that the lower first electrode may be made of not only chromium but also other conductive films having sublimation properties, such as molybdenum or chromium compounds. Further, in order to improve the low optical reflectance of chromium and thus improve the conversion efficiency of the device, 0.1 to 50% by weight of copper or silver, for example 2.0 to 10% by weight, was added to Cr.

(1) Cr (300-5000 people), (2) Cr
-Cu (2.5% by weight) (300-5000 people) (3
) Cr-8g (2.5% by weight) (300-5000 people) was excellent in LS processability.

When using chromium (1) in these electrodes, the semiconductor underneath is also completely removed by LS, resulting in a high manufacturing yield.

However, due to its low reflectance, its long wavelength light characteristics are poor.

The other (2>, <3) chromium t added with silver and copper
The reflectance of light was improved by 5 to 20% compared to chromium alone, and the laser processability was ideal as there was no problem with laser processing.

The first groove (13) formed by the first LS was approximately 50 μm wide and 20 cm deep to completely cut each of the electrodes of the first conductive film and electrically isolate them.

Thereafter, a non-single crystal semiconductor layer (3) that generates photovoltaic force by light irradiation is deposited on the upper surface of the electrode (2) and the opening (13) by a plasma CVD method or an LPCVD method.
It was formed to an average thickness of ~1.0μ, typically 0.7μ.

A typical example is N-type microcrystalline semiconductor-I on ITO (15).
Type amorphous or semi-amorphous silicon semiconductor (approximately 0.7 μ) - non-single crystal semiconductor of semiconductor silicon with P type microcrystals (approximately 500), and on top of this 5ix
Non-single crystal semiconductor or P-type semiconductor (SixGe 1-X) - 1-type, N-type, P-type Si semiconductor - which has one NIP junction by stacking C1-x (x = 0.9 about 50 people) I-type Si semiconductor - N-type 5ixC1-) < Tandem type PINFIN having two PIN junctions and one PN junction made of semiconductor,
).

Furthermore, as shown in FIG. 1(B), a first open groove (1
A second open groove (18) was formed over the left side (first element side) of 3) by the second LSI process.

In this drawing, the first and second open grooves (13), < 18
) are shifted by 100μ.

The second open groove (18) thus forms a side surface (8) of the first electrode.
Or the side and top surfaces (9) (11]O~5μ) were exposed.

Furthermore, this substrate was heated for 10 seconds in dilute hydrofluoric acid (1/10 liver prepared by diluting 48% IIF with 10 times water was used here).
Etching time was typically 30 seconds.

As a result, it was possible to remove low-grade porous silicon oxide produced by reaction of the semiconductor (3) and the conductive film (2) with oxygen in the atmosphere during LS.

Next, chromium or chromium uricide was formed on this semiconductor to a thickness of 20 to 200 nm by electron beam evaporation. The substrate temperature at this time is 100 to 300℃, for example 20℃.
It is 0°C. Furthermore, since this atmosphere is a vacuum, thermal annealing is performed for 30 minutes to 1 hour after forming this film, and T
CNO was formed. Furthermore, there is a translucent IT on this surface.
T(:N
A conductive film for the second electrode of 2I- of O and TCO was formed. This ITO had a transmittance of 87% (500 μm) and a sheet resistance of 20Ω/hole. TCNO has a transmittance of 85% (5
00 μm), and the sheet resistance was 3'Ω/mouth.

Next, in FIG. 1(C) of the present invention, the third open groove (20) is inserted into the third groove so that the chromium (45) constituting the second electrode and the connector (30) do not electrically short-circuit. 1 element area (31).

That is, the electrode (39) where the open circuit voltage of the first element is generated.

(3B) Electrical separation between
(typically 50 μφ) from the second open groove (1B) by about 10
They were formed with a spacing of 0μ. That is, the third opening ei (20
) is 100~ compared to the center of the second open groove (30).
It is provided at a depth of 200μ, typically 150μ, over the first element side.

This LS removed the semiconductor under the TCNO without damaging it. FIG. 1(C) shows such a drawing.

Thus, as shown in FIG. 1(C), a plurality of elements (
31), < 11) were directly connected to the CTF (15) of the f-base and the connecting portion (12) formed by connecting chromium.

FIG. 1(D) shows the attempt to further complete the present invention as a photoelectric conversion device, that is, a silicon nitride film (21) with a thickness of 500 to
The film was formed uniformly to a thickness of 2,000 mm to prevent leakage current between each element due to adsorption of moisture, etc., and to form an anti-reflection film.

In this way, the photovoltaic force generated by the irradiation light (10) flows from the first electrode of the first element to the second electrode of the second element as shown by the arrow (32) from the side surface or the contact between the side surface and the top surface. I was able to make a series connection.

As a result, on this board (60cm x 20cm), each element was connected to +11150/
J, 10 mm in the middle of the external extraction electrode part and 4 mm in the peripheral part, so there are essentially 40 stages within 580 mm x 192 mm, and the effective area (192 mm x 14.35 mm 40
stage 1102 cnl, or 91.8%).

If the segment has a conversion efficiency of 9.5% (1,05 cm), then the panel has a conversion efficiency of 6.4% (theoretically 8
．． 1%, but the effective conversion efficiency decreased due to the resistance of the 40-stage connection)
), it was possible to have an output power of 6.4-.

Furthermore, when this panel was subjected to a high temperature storage test at 150° C., a decrease of 10% or less was observed after 1000 hours, for example, when the number of panels was 20, a decrease of X = 3.3% was observed.

This was an astonishing value considering that when a reliability test was conducted under the same conditions using the conventional mask method, as many as 17 panels were rendered inoperable in 10 hours.

Also, this panel for example 40cm x 60cm or 6
0cm x 20cm, 40cm x 120cm 2
Packaged by combining 4 pieces or 1 piece in an aluminum sash or carbon fiber frame, 120 cm
It is possible to provide a high power panel of 40cm x NP and DO standards.

In addition, this NEDO standard panel uses Seaflex to adhere a fluorine-based protective film to the reflective surface side (upper side in the drawing) of the charging conversion device of the present invention to increase mechanical strength against wind pressure, rain, etc. It is self-effective.

Further, the details of the present invention will be supplemented by describing examples below.

Example 1 This embodiment is not shown according to the drawing in FIG.

That is, a stainless steel foil (16) (thickness: 50 μm), length: 60 cm, and medium: 20 cm was used as the transparent substrate (1).

Polyimide resin (17) was applied to the top surface to a thickness of 3 μm to form a blocking layer.

Further, chromium mixed with 2.5% copper was formed thereon to a thickness of 1000 mm by magnetron sputtering. Furthermore, ITO was simultaneously formed on it to a thickness of 1050 by sputtering.

Furthermore, after this, a first open groove was formed at a scanning speed of 0.3 m/min by controlling a G laser with a spot diameter of 50 μm and an average output of 0.7 W using a microcomputer.

Further, the first electrode semiconductor was scanned in a rectangular manner on the edge of the panel with a laser beam average output of 0.7 using a trowel at a distance of 5 mm inside the edge of the glass to prevent an electrical short circuit with the frame of the panel. The element regions (31) and (11) were set to 15 mm.

Thereafter, a non-single crystal semiconductor having one PIN junction as shown in FIG. 2 was manufactured by a known PCVD method.

Its thickness was approximately 0.7μ.

After this, the first element (31) is removed by 100μ from the first groove.
was shifted, and a second open groove (18) was produced as shown in FIG. 1(B) by LS in the atmosphere with a spot diameter of 50 μφ and an output IW.

Further, chromium was formed on the upper surface to a thickness of 20 mm by electron beam evaporation. Thereafter, heat treatment was performed at 200° C. for 1 hour, and ITO was further produced to a thickness of 500 using the same vapor deposition apparatus.

Furthermore, the third open groove (20) is similarly connected to the third LS by YAG.
Using a laser, 0.6 W (scan speed 30c
The second open groove (1
8), the layer was shifted to the first element (31) side to a depth of 150 μm, and FIG. 1(C) was obtained.

Thereafter, a silicon nitride film was formed to a thickness of 600 mm using the PCVO method at a substrate temperature of 200° C. (film formation time: 30 minutes) to form a pansivation film (21).

Then, 15mm 1J is applied to a 20cm x 60cm panel.
We were able to fabricate 40 stages of elements.

The effective efficiency of the panel is 8Ml (100mW/
CIA), we were able to obtain an output of 8.1% and an output of 6.4W.

The effective area is 1102cJ, and the total panel area is 91.8
% could be used effectively.

In FIG. 1, light was incident from the upper transparent insulating substrate.

In the present invention, it is better to form the second groove (18) only inside the semiconductor than from one side of the semiconductor to the other to reduce the occurrence of short circuits or leaks between electrodes due to integration. Ta. Also, the second open groove is 1
In the case of the photoelectric conversion device of the present invention, which is applied to a calculator, etc., it is also effective to use a continuous method using a plurality of openings and contacts inside the semiconductor.

In such a case, one element is 1 cm x 1 cm, and it goes without saying that the integrated structure can be as small as 1 cm x 5 to 10 cm.

In the present invention, the substrate is an organic resin insulating film on a stainless steel foil. However, it goes without saying that this substrate may be made of organic resin or may be made of aluminum foil and the upper surface thereof may be made of aluminum oxide.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing the manufacturing process of the photoelectric conversion device of the present invention. Patent applicant 1 (r)2 I1ω

Claims (1)

[Claims] 1. A first electrode of a conductive film on a substrate having an insulating surface;
A plurality of photoelectric conversion elements each having a non-single-crystal semiconductor that generates a photovoltaic force by light irradiation on the electrode and a second electrode on the semiconductor are electrically connected in series on the insulating substrate. A photoelectric conversion device disposed in a photoelectric conversion device, wherein the second electrode of the element comprises a non-oxide light-transmitting conductive film and an oxide light-transmitting conductive film. 2. In claim 1, the non-oxide transparent conductive film is mainly composed of a mixture (compound) of chromium and silicon, and the upper surface thereof is mainly composed of indium oxide or tin oxide. A photoelectric conversion device characterized by being provided with a film. 3. A first electrode of a conductive film on a substrate having an insulating surface;
A plurality of photoelectric conversion elements each having a non-single-crystal semiconductor that generates a photovoltaic force by light irradiation on the electrode and a second electrode on the semiconductor are electrically connected in series on the insulating substrate. In the method for manufacturing a photoelectric conversion device disposed in
1. A method for manufacturing a photoelectric conversion device, comprising the step of forming an oxide light-transmitting conductive film containing tin oxide or indium oxide as a main component. 4. In claim 3, after holding the non-single crystal semiconductor in a non-oxidizing atmosphere at 100 to 300°C, a metal containing chromium as a main component or a compound of silicon and chromium (
A step of forming a mixture (mixture) to a thickness of 10 to 200 mm and subjecting it to heat treatment, and a step of forming a translucent oxide conductive film containing tin oxide or indium oxide as a main component after the step. A method for manufacturing a photoelectric conversion device characterized by the following.