JPS62259479A - Photovoltaic device - Google Patents

Abstract

PURPOSE:To improve effective photodetecting area of a photovoltaic device with respect to the area of a substrate by minimizing a connecting extension for electromechanically connecting to a width to cover a connecting hole. CONSTITUTION:Electrodes 2a-2c, 4a-4c of first generating zone and second generating zone disposed adjacent to the first zone have connecting extensions 21a-21c, 41a-41c at the side edges of the generating zones in the arranging direction, and the extensions 21a-21c of the electrodes 2a-2c are so disposed that at least parts of the extensions 41a-41c of the electrodes 4a-4c of the second generating zone are opposed at both sides of an amorphous semiconductor layer 3. The layer 3 has connecting holes 5 at the opposed portions of the extensions, and the extensions 21a-21c of the electrodes 2a-2c and the extensions 41a-41c of the electrodes 4a-4c are electrically connected through the holes 5. Accordingly, electromotive forces of the generating zones are output in series.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photovoltaic device having an amorphous semiconductor layer used in solar cells, optical sensors, and the like.

[Conventional technology]

A conventional photovoltaic device is shown in FIGS. 3(a) and 3(b).

FIG. 3(a) is a plan view of a conventional photovoltaic device, and FIG. 3(b) is a sectional view taken along line AA' in FIG. 3(a).

A plurality of first electrodes 2g to 21 are formed on the insulating substrate 1. The amorphous semiconductor layer 3 is continuously deposited on the plurality of first electrodes 2g to 21, and further, the first electrodes 2g to 21 are covered with an amorphous semiconductor layer 3.
21, second electrodes 4g to 41 are provided on the amorphous semiconductor layer 3.
is formed.

As a result, a plurality of power generation areas g to i are formed on the insulating substrate 1.

When forming the first electrodes 2g to 21, the first electrodes extending outside the amorphous semiconductor layer 3 are formed using a mask operation or an etching process.
Extensions 21g to 21i for electrode connection are formed. Furthermore, when forming the second electrodes 4g to 41, by operating the mask, the first! The second Ti pole connection extensions 41h to 4 are connected so as to overlap and connect with the pole connection extensions 21g to 21h.
1i is formed. Incidentally, the connecting extension part 41g of the second electrode of the power generation area g is formed as it is outside the amorphous semiconductor layer 3, and the first! A lead wire extraction terminal portion 61 is formed on the pole connection extension portion 21i.

In this way, the connection extensions 21g to 21h of the 11i-pole and the connection extensions 41h to 41i of the second pole are connected in an overlapping manner as described above, thereby creating a photovoltaic system in which the power generation areas g to 1 are connected in series. A power device is achieved. The electromotive force of the photovoltaic device described above is generated by the connection extension 4 of the second electrode of the power generation area g.
1g and the terminal portion 61 for taking out the lead wire.

(Refer to Japanese Patent Publication No. 5B-21827) [Problems with the Prior Art] However, in the conventional photovoltaic device, since the connection part C of the power generation area is provided outside the power generation area, 1 of the total area of the substrate 1 is
5 to 20[chi] is occupied by the connection part C which does not contribute to power generation at all, and the effective light-receiving area (portion G to which the amorphous semiconductor N3 is attached) with respect to the area of the substrate 1 is extremely reduced. For example, when this photovoltaic device is used as a power source for a calculator, a watch, etc., not only does the substrate 1 become extremely large in proportion to the effective light receiving area in order to achieve a predetermined current value, but also the In order to cover the portion C, a cover member is required, and there is a problem in that the internal layout of the calculator, clock, etc. is restricted, and the device becomes larger.

Furthermore, in the above-described photovoltaic device, when forming the amorphous semiconductor layer 3, the extension portion 21g of the first electrode, which becomes the connection portion C.
A mask having a window of a predetermined shape is used to prevent the amorphous semiconductor N3 from being deposited on the semiconductor layer 21i.

However, when the amorphous semiconductor layer 3 was deposited, plasma interference occurred on the mask, leaving interference fringes on the amorphous semiconductor layer 3, especially at the window edge portion of the mask, and deteriorating the film quality of the amorphous semiconductor 1i3. . For this reason, there was a problem that the output of the above-mentioned photovoltaic device could not be sufficiently derived. Furthermore, if the mask is continued to be used for a long period of time, the mask may be damaged or distorted by plasma, etc., and the amorphous semiconductor layer 3 may enter the gap between the mask and the substrate 1, or the highly accurate mask positioning may become difficult. This makes it difficult to control fine processing of the amorphous semiconductor N3 due to difficulties in processing and misalignment of the mask. This lowered the yield of the above-mentioned photovoltaic device.

[Purpose of the invention]

The present invention has been devised in view of the above problems,
The purpose is to provide a photovoltaic device that has an increased effective light-receiving area with respect to a substrate and can obtain high output characteristics.

[Specific means to achieve the purpose]

The specific means taken by the present invention to achieve the above-mentioned object includes an amorphous semiconductor layer and a first layer formed on the upper and lower surfaces of the amorphous semiconductor layer. In a photovoltaic device in which at least two power generation areas consisting of a second electrode and a second electrode are arranged and formed on an insulating substrate, a first power generation area and a second power generation area arranged adjacent to the first power generation area are arranged.
Each electrode of the power generation areas has a connection extension part on a side edge in the arrangement direction of the power generation areas, and the connection extension part of the first electrode of the first power generation area has an amorphous semiconductor layer in between. The amorphous semiconductor layer is disposed such that at least a portion thereof faces the connection extension of the second electrode of the second power generation area, and the amorphous semiconductor layer has a connection opening in a portion opposite to the connection extension. , the connection extension of the first electrode of the first power generation area and the connection extension of the second electrode of the second power generation area are electrically connected through the connection opening, whereby each power generation The electromotive force of each area is output in series.

〔Example〕

Hereinafter, the photovoltaic device of the present invention will be explained based on the drawings. Note that the same parts as those in the prior art are given the same reference numerals.

FIG. 1(a) is a plan view of the photovoltaic device of the present invention,
FIG. 1(b) is a sectional view taken along line XX' in FIG. 1(a), and FIG. 1(c) is a sectional view taken along line Y-Y' in FIG. 1(a).

Reference numeral 1 denotes an insulating substrate, and the insulating substrate 1 is made of translucent glass, ceramic, or stainless steel whose surface is subjected to insulation treatment.

First electrodes 28 to 2c are arranged over almost the entire surface of the substrate 1, respectively. At the same time, connection extensions 21a to 21c are formed on the side edges of each of the first electrodes 2a to 2c in the arrangement direction. Specifically, a transparent conductive film made of tin oxide (SnO□), indium tin oxide (ITO), or the like is formed to a thickness of 500 to 1000 layers by sputtering or plasma CVD.

Reference numeral 3 denotes an amorphous semiconductor layer, and the amorphous semiconductor layer 3 is deposited over the entire surface of the substrate 1 so as to be continuous on the first electrodes 28 to 2c and the connection extensions 21a to 21c.

The amorphous semiconductor layer 3 is provided with a P-1-N junction so that holes and/or electrons are generated by light irradiation.

Although not shown, the second layer has 100 to 200 people, and the first layer has 5 people.
000 to 7,000 people, N layer is 300 to 700 people,
The overall thickness of the amorphous semiconductor N3 is about 0.5 to 0.8 μm.

Reference numeral 5 denotes a connection opening formed in a straight line along the arrangement direction in a part of the amorphous semiconductor N3 on the extensions 21a to 2c of the first electrodes 2a to 2c. A part of the amorphous semiconductor layer 3 is removed and penetrated through the connection opening 5, and the first electrodes 2a to 2c and the substrate 1 are exposed.

As a specific method for forming the connection opening 5, Nd-
A YAG laser was used, the frequency of the laser oscillation switch was 2 KHz, and the scanning speed of the laser beam on the W board was 100 mm/SEC. As a result, the width of the connection opening 5 becomes a linear groove of 50 μm.

The width of the connection opening 5 is determined by the output of the laser.
A minimum thickness of 20 μm is sufficient. In addition, the Q of laser oscillation
The frequency of the switch and the laser beam scanning speed with respect to the substrate 1 can be set to predetermined values to prevent damage to the first electrodes 28 to 2c, and small holes with a diameter of at least 20 μm can be formed intermittently. can.

4a to 4c are second poles, and the second electrodes 4a to 4c are formed on the amorphous semiconductor layer 3 at positions approximately corresponding to the first electrodes 28 to 2c. Specifically, metals such as nickel (Ni), aluminum (AI), titanium (Ti), and chromium (Cr) are formed using a resistance heating method, a sputtering method, or the like.

As a result, a power generation area a''-'c is formed on the substrate 1. The electrical connection of the power generation area a''-'c is made with the second electrode 4.
When forming electrodes a to 4c, connection extensions 41a to 41c of the second electrodes 48 to 4c are simultaneously provided by mask operation or etching process, and the connection extensions 41b to 41c are formed at the same time.
are connected to the connecting extensions 21a-21b of the first electrodes 2a-2b of the adjacent power-generating areas a''b through the connecting openings 5, thereby achieving a series connection of the power-generating areas ac.

Thus, the output of a photovoltaic device having each power generation area a-c electrically connected in series is the same as that of the second electrode 4 of power generation area a.
Output terminal portion 6c formed on connection opening 5 through which connection extension 41a of a and first electrode 2c of power generation area C are exposed.
It can be obtained from between.

Note that since the resistance R8 between each power generation area is larger than the resistance Ro in the thickness direction of the amorphous semiconductor layer 3, even if the amorphous semiconductor layer 3 is formed continuously, the resistance R8 between each power generation area Leakage current can be ignored.

According to the present inventors, it has been confirmed that if the width of the connection opening 5 to which the connection is made is at least about 20 μm, there will be no problem with an output of about 20 μA, and this will contribute to the connection. It is extremely easy to minimize the connecting portion and design the effective area of the substrate 1 to be 90% or more. In addition, by simply forming one linear connection opening 5 in the arrangement direction of power generation areas a-c, multiple power generation areas a"
-'c can be easily electrically connected in series.

In order to compare the output characteristics of the above-described photovoltaic device and a conventional photovoltaic device, the present inventors made the first electrode and the second electrode the same size and the same shape, and conducted measurements under the same conditions.

As a result, it was confirmed that the short circuit current 1sc of the photovoltaic device of the present invention was improved by about 10 to 15χ compared to the conventional photovoltaic device. This is because the effective light-receiving area has increased, and since the amorphous semiconductor layer 3 is deposited on the entire surface of the substrate without a mask, there is no damage to the amorphous semiconductor layer 3 or variation in film quality due to mask interference, etc. This seems to be caused by.

FIG. 2(a) is a plan view showing another embodiment of the photovoltaic device of the present invention. Figure 2(b) is V-V in Figure 2(a).
2(c) is a sectional view taken along the z-line in FIG. 2(a).
It is a z' line sectional view.

Rectangular first electrodes 2 d to 2 f are arranged and formed on the substrate 1 . At this time, a first electrode 2d is attached to the side edge of each electrode 2d to 2f.
~ Connection extension part 21d that has the same width as 2f and contributes to the connection ~
21f is formed at the same time.

The amorphous semiconductor layer 3 is deposited to completely cover the first electrodes 2d to 2f and their connecting extensions 21d to 21f.

5 is an amorphous semiconductor layer 3 on the connection extensions 21d to 21f.
The connection opening 5 is formed in a straight line on the connection extensions 21d to 21f of the first electrode along the power generation area direction by laser irradiation. Furthermore, a plurality of second electrodes 4d to 4f are formed on the amorphous semiconductor N3 at positions corresponding to the first poles 2d to 2f.

As a result, a plurality of power generation areas df are formed on the substrate 1.

When forming the second electrodes 4d to 4f, the same power generation areas d to f
A connecting extension part 41 that extends to the adjacent power generation areas d so as not to contact the first electrodes 2d to 2f of the power generation areas d and the second electrodes 4d and 4d of the adjacent power generation areas d and e.
e to 41f are formed. Accordingly, the connection extensions 41e to 41f are connected to the connection extensions 21d to 21e of the first electrodes of the adjacent power generation areas dxe through the connection openings 5.
are electrically connected to achieve a series connection of power generation areas d-f.

Thus, the output of the photovoltaic device having each of the power generation zones d - f connected in series is determined by the connection where the second electrode 4d of the power generation zone d and the extension 21f of the first electrode 2f of the power generation zone f are exposed. It is obtained from between the output terminal portion 6f formed on the opening portion 5.

In the above-mentioned embodiments, it should be noted that in some cases, the connection extension part is apparently provided on the second electrode, and each power generation area is connected in series, and the connection extension part is provided on the first and second electrodes, respectively. Although a photovoltaic device in which a connecting extension is provided on the first electrode side and each power generation area is connected in series is shown, a photovoltaic device may be used in which each power generation area is connected in series.

In addition, although the above-mentioned example shows a photovoltaic device having a substrate/transparent electrode/amorphous semiconductor layer/metal electrode, a photovoltaic device having a structure of a substrate/metal electrode/amorphous semiconductor layer/transparent electrode is shown. It may be.

〔effect〕

As mentioned above, according to the photovoltaic device of the present invention,
an amorphous semiconductor layer; and a first layer formed on the upper and lower surfaces of the amorphous semiconductor layer. A photovoltaic device in which at least two power generation areas each consisting of a second electrode and a second electrode are arranged and formed on an insulating substrate,
Each electrode of the first power generation area and the second power generation area arranged adjacent thereto has a connecting extension part on a side edge in the arrangement direction of the power generation area, and the first electrode of the first power generation area The connecting extension of the second power generating area is arranged to at least partially face the connecting extension of the second pole of the second power generation area with the amorphous semiconductor layer interposed therebetween; The connection extension has a connection opening in an opposing portion, and the connection extension of the first electric scraper of the first power generation area and the connection extension of the second electrode of the second power generation area are connected to each other. Since electrical connection is made through the connection opening, and thereby the electromotive force of each power generation area is output in series, the connection extension for electrical connection must be wide enough to cover the connection opening. Since the area of the connecting portion of the board can be drastically reduced, the effective light-receiving area relative to the board area can be improved. Even when this is implemented in electronic devices such as calculators and watches, the unsightly connecting parts become extremely small, making it possible to downsize the electronic devices. Furthermore, since the number of photovoltaic devices that can be obtained from a manufacturing substrate increases, the price of each photovoltaic device becomes cheaper.

Furthermore, since no masks are used when depositing the amorphous semiconductor layer, there is no interference from the amorphous semiconductor layer, resulting in a photovoltaic device with improved appearance quality and stable output. can.

[Brief explanation of drawings]

FIG. 1(a) is a plan view of an embodiment of the photovoltaic device of the present invention, FIG. 1(b) is a cross-sectional view taken along line XX' in FIG. 1(a), and FIG. (c) is a sectional view taken along the line Y-Y' in FIG. 1(a). FIG. 2(a) is a plan view of another embodiment of the photovoltaic device of the present invention, and FIG. 2(b) is a sectional view taken along the line V-V' in FIG. 2(a). Figure 2 (c) is 2-Z'' in Figure 2 (a).
FIG. FIG. 3(a) is a plan view of a conventional photovoltaic device, and FIG. 3 is a sectional view taken along line AA' in FIG. 3(a). 2a-21...First electrodes 4a-41...Second electrode 3...Amorphous semiconductor layer 5...Connection opening

Claims (1)

[Scope of Claims] A photovoltaic device in which at least two power generation areas each consisting of an amorphous semiconductor layer and first and second electrodes formed on the upper and lower surfaces of the amorphous semiconductor layer are arranged and formed on an insulating substrate. In the power device; each electrode of the first power generation area and the second power generation area arranged adjacent thereto has a connecting extension part on a side edge in the arrangement direction of the power generation area; the first power generation area; The connecting extension of the first electrode is arranged so that at least a part thereof faces the connecting extension of the second electrode of the second power generation area with the amorphous semiconductor layer in between; The semiconductor layer has a connection opening in a portion opposite to the connection extension; for connection of the connection extension of the first electrode of the first power generation area and the second electrode of the second power generation area. The photovoltaic device is characterized in that the extension portion is electrically connected through the connection opening, so that the electromotive force of each power generation area is output in series.