JPS60143676A - Photovoltaic device - Google Patents

Abstract

PURPOSE:To obtain a device which can obtain high output voltage by connecting in series plural amorphous semiconductor solar cell elements. CONSTITUTION:An amorphous semiconductor solar cell element 2 which constitutes a photovoltaic device 1 is the laminating of an amorphous semiconductor layer 6 on such a conductive substrate 4 as a stainless steel thin plate or a thin iron plate. The semiconductor layer 6 can be made a p-n construction, a n-p construction or a tandem construction piled in two layers of these two constructions. A long size conductive substrate wherein amorphous silicon layers are piled is cut, a transparent conductive film 8 is formed on the semiconductor layer 6 and the solar cell element 2 of W wide and L long is formed. The element 2 is so placed on an insulating substrate 30 that the ends (d) of the adjacent elements 2a and 2b are piled. Then, at the right ends of the elements 2a, 2b, 2c,..., a passivation film 24 is formed and a leak between the substrates of each element is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates generally to photovoltaic devices;
In particular, the present invention relates to a photovoltaic device constructed by electrically connecting a plurality of amorphous semiconductor batteries. In this specification, amorphous semiconductor is used to include microcrystallized semiconductor.

In recent years, AMO/I/7A semiconductors, such as amorphous silicon solar cells, have (1) been thin films, that is, have a larger absorption coefficient in the visible light range than crystallized silicon, and have a conversion efficiency comparable to that of crystalline silicon. 12) The power required to manufacture γmol 7As silicon solar cells is much lower than that of crystalline silicon solar cells, resulting in a lower energy recovery rate; (3) Substrate heating (4) Amorphous silicon does not react with the substrate, and various substrates such as stainless steel plates and glass plates can be used. It is attracting attention as a component of photovoltaic devices because it can be easily produced in a continuous manner.

However, the output per unit area of an amorphous silicon solar cell is extremely small, and therefore, in order to generate a large amount of power that can be put to practical use, it is essential to increase the surface area of the solar cell.

It has been found that when the surface area of a single solar cell element is increased in order to solve this drawback, the efficiency decreases due to the sheet resistance of the transparent conductive layer that constitutes the surface area of the element. Furthermore, it is technically more difficult to manufacture such a large solar cell, resulting in a disadvantage of lower yield.

Among the above-mentioned disadvantages, in order to overcome the reduction in efficiency due to the sheet resistance of transparent conductive layers, integrated solar cells are formed in which multiple solar cell elements are formed on an insulating substrate and each solar cell element is connected in series. However, the manufacturing process is complicated and the manufacturing cost is high, and the effective power generation area is small compared to the area occupied by the element, which means that the practical efficiency is low. Furthermore, even in the integrated type, for example, to make a 201 square cell, amorphous silicon or the like must be deposited on a 201 square substrate, which inevitably lowers the yield due to the larger area.

Therefore, the main object of the present invention is to provide a photovoltaic device having a large area, high efficiency, and low cost.

Another object of the present invention is to provide a photovoltaic device configured by connecting a plurality of amorphous semiconductor solar cell elements in series and capable of obtaining a high output voltage.

Next, a photovoltaic device according to the present invention will be explained with reference to the drawings.

FIG. 1 shows an amorphous semiconductor solar cell element 2 constituting a photovoltaic device 1 of the present invention. In the amorphous semiconductor solar cell element 2, an amorphous semiconductor layer 6 is laminated on a conductive substrate 4 made of, for example, a thin stainless steel plate. Here, as the conductive substrate 4, another metal substrate such as a thin iron plate can be used.

In this embodiment, the amorphous semiconductor layer 6 is made of pi
It can be an n structure, an nlp structure, or a tandem structure in which these structures are stacked in two layers. Also, the p layer, 1 layer and n layer can be amorphous silicon layers,
A microcrystalline silicon layer may be used for the p layer and the n layer, and an amorphous silicon germanium layer may be used for the tm.

The amorphous semiconductor layer 6 shown in FIG. 1 has a pin structure in which an amorphous silicon p-type layer 6m, an amorphous silicon l-type layer 6b, and an amorphous silicon n-type layer 6c are sequentially laminated from the substrate 4 side. A transparent conductive film 8 is formed on the upper layer.

As mentioned above, the amorphous solar cell element 2 is not limited to the element structure shown in FIG. Conductive film, M plate/p (amorphous silicon - fish (amorphous silicon germanium) -
n-p-1-n (amorphous silicon)/transparent conductive film (tandem structure) can be considered.

Next, we will discuss a second method for manufacturing a solar cell element 2 having a p-1-n (amorphous silicon) structure shown in FIG.
This will be explained with reference to the figures.

FIG. 2 schematically shows the structure of the amorphous silicon deposition apparatus 10. As shown in FIG. The apparatus 10 has a p-type layer forming chamber 12, a side layer forming chamber 14, and an n-type layer forming chamber 16 inside. Each chamber 12.14 and 16
are paired electrodes 18a, b, 20a, b and 22aX
a glow discharge device 18, 20 and 22 with b.

Further, the elongated conductive substrate 4 passes through each of the chambers 12, 14 and 16, that is, between the pair of electrodes in each chamber, from the supply p-layer 4a to the take-up p-rule 4b. Supplied.

Furthermore, each chamber 12.14 and 16 is supplied with a predetermined dopant gas. That is, the chamber 12 contains Si.
Mixed gas of H4 and B2H, SiH4 in chamber 14
A mixed gas of PH3, 81H4 and H2 is supplied to the gas and chamber 16.

The conductive substrate 4 is, for example, a thin stainless steel plate with a thickness of 11 m and a width of 20 cH1, and is conveyed from the supply roll 4& side to the winding roll 4b side through between the electrodes of each chamber.

On the substrate 4, a p-type layer 6m is deposited in the chamber 12, then an l-type layer 6b is deposited on the p-type layer 6a in the chamber 14, and finally, the 1-type layer 6m is deposited in the chamber 16. An n-type layer 6C is further deposited on 6b. In this way, the amorphous silicon layer 6 is continuously deposited on the conductive substrate 4.

The elongated conductive substrate on which the amorphous silicon layer is deposited has a width of 5 to 50 degrees in the longitudinal direction, preferably 10 to 30 degrees.
It is sequentially cut at 1111 widths.

Each cut amorphous silicon layer phase substrate is introduced into a vapor deposition apparatus and a transparent conductive layer 8 is formed on the amorphous silicon layer 6 in the usual manner.

As a result, the width (W) 2
01? FF+, an amorphous silicon solar cell element 2 having a length (L) of 5 to 50 mm is manufactured. The length L) of the solar cell 2 is set to be 5 to 50 mm as described above, but it is preferable to set the cutting width, that is, the length L) to less than 5 mm, as this will decrease the production speed and increase the production cost. In addition, if the length L) is set to 501111 or more, the efficiency of the thick VwJ battery will decrease due to the sheet resistance of the transparent conductive layer 8, and the yield will further deteriorate, which is undesirable.

Furthermore, if desired, a passivation film 24 can be applied to one end of the solar cell element 2, as shown in FIG. The passivation film 24 has a width (D) on the upper surface of the amorphous silicon layer 6 before the transparent conductive layer 8 is deposited.
It is provided so as to extend over α2~2 and reach the substrate 4 from the upper surface along the end surface. This passivation film 24 is 5in4 and O! It can be a 5102 or SiN4 film formed by a plasma CVD method using a mixed gas of 5IH4 and NH3, or an insulating organic film formed by coating an appropriate organic material. I can do it. By applying such a passivation film 24, as will be described later, it is possible to prevent a decrease in yield due to leakage between the substrates of each solar cell element connected in series. Moreover, the passivation film 24
The conversion efficiency of the solar cell does not decrease by applying this.

As shown in FIG. 4, the amorphous silicon solar cell element 2 manufactured as described above is placed on an insulating substrate 50, for example, a plastic substrate, on which two adjacent solar cell elements 2a and 2b are placed. The ends are arranged in alignment so that they overlap each other. To be more specific,
The left end of the second solar cell element 2b located immediately adjacent to the first solar cell element 2a is overlapped with the right end of the #81 solar cell element 21 by a width (d). Further, the left end of the third solar cell element 2C located immediately adjacent to the second solar cell element 2b has a width (d) at the right end of the second solar cell element 2b.
) can be superimposed. At this time, if the passivation film 24 is applied to the right end of the solar cell elements 21% 2b, 2 cm1, . . . as described above, leakage between the substrates of each solar cell element can be prevented. After that, the desired number of fat li! The battery elements are arranged in a series connection manner as described above, and the photovoltaic device 1 is constructed.

Each solar cell element 2 (21LN 2 bs 2 es
"') is a portion where the conductive substrate 4 side is fixed to the insulating substrate 60 with a suitable adhesive and overlaps each other,
In other words, electrical connection is established between the transparent conductive film 8 of one solar cell element and the conductive substrate of the other solar cell element by using a conductive adhesive such as silver paste. Guaranteed. The length d) of the overlapping portion can be set to any size from the viewpoint of solar cell efficiency, but considering ease of production, raw material cost, etc.
α5-5- is preferred. Also, the passivation film width (
D) will be smaller than the joining part (d).

By the above method, for example, a thick li1 with a width (W) of 20 cm and a length of I,) of 12 m! By arranging and integrating the battery elements 2 on the insulating substrate 30 so that two overlapping portions (d) overlap with each other, the photovoltaic device 1 having a square size of 20 crR can be easily manufactured.

The photovoltaic device according to the present invention configured as described above has the following features: (1) Each solar cell element has an arrangement of, for example, 20cIR×t2c
(2) Each solar cell element has a relatively small area of 1n, and can maintain high conversion efficiency and yield.
It may be arranged in series such as stages, e.g. 16
■It is possible to obtain a practical high output voltage such as
(3) Electricity is generated over almost the entire area of the photovoltaic device, for example, 20°, and the area efficiency is extremely high. (4)
Kaede has the advantage of being able to use low-cost materials such as thin stainless steel plates as the four-conductor substrate, and providing a low-cost thick VJ battery and, therefore, a low-cost photovoltaic device.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an amorphous semiconductor solar cell element. FIG. 2 is a schematic cross-sectional view of an apparatus for manufacturing an amorphous silicon device. FIG. 3 is a front view of the amorphous semiconductor solar cell element. FIG. 4 is a partial front view of a photovoltaic device according to the present invention. 1: Photovoltaic device 2: Amorphous semiconductor solar cell element 4: Conductive substrate 6: Amorphous semiconductor layer 8: Transparent conductive layer 24: Pansivation film Ward ~ Procedural amendment (method) 1980 4 Jl 26 Indication of the case of Kazuo Wakasugi, Commissioner of the Patent Office, 1982, Patent Application No. 251962, Title of the grand invention Relationship with the case of person who corrects photovoltaic devices Name of patent applicant: Agent of Toagu Ryoko Liang Co., Ltd. Address: 103 Weight of notice of amendment order March 27, 1980 - 幇hto 纹目トカ → Sori + 1 + rishi beak ji manma row makishita subject of amendment 4th layer e to ~ and 辷 + - 1 drawing 1 copy Contents of amendment to the description As shown in the attached sheet

Claims (1)

[Claims] 1) A plurality of thick battery elements each formed by laminating a conductive substrate, an amorphous semiconductor layer, and a transparent conductive film layer are arranged in series, and adjacent solar battery elements are connected to one solar cell. A photovoltaic device comprising a transparent conductive film layer of a battery element and a conductive substrate of another solar cell element electrically connected in series so as to partially overlap with each other. 2) The device according to claim 1, wherein the amorphous semiconductor layer has a pin structure, an nlp structure, or a tandem structure in which two layers of pln or nlp structures are stacked. 3) The device according to claim 2, wherein the p-layer, 1-layer and n-layer are all amorphous silicon layers. 4) The device according to claim 2, wherein the p-layer and/or the n-layer are microcrystalline silicon layers. 5) The device according to claim 2, wherein one layer is an amorphous silicon germanium layer. 6) The device according to claim 1 or 2, wherein the conductive substrate is a thin stainless steel plate or a thin iron plate. 7) The device according to any one of claims 1 to 6, wherein a passivation film is provided on the end face of the thick battery element.