JPS60160181A - Amorphous solar cell - 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] [Technical field of invention] This invention relates to amorphous solar cells.

[Prior art]

In general, solar cells are not used as a single unit 11, but are usually used in the form of a module in which a plurality of cells are connected in series or in series and parallel.

This is because the output voltage of one cell is low, being about 0.4 to 1.0 V, although it varies depending on the material of the cell, and it is difficult to use it as a single cell. Since the individual cells constituting the series-connected modules are diodes, they have the following problems.

In other words, when the module is partially shaded and the cells in the snow area stop generating electricity, the total voltage of the other cells that are generating electricity without being shaded becomes a single bias, and the cell that stopped generating electricity becomes It comes down to To be specific, 10
If one of the 10 cells in a module with an output voltage of IOV is shielded from light in series, when a reverse bias of 9V is applied to this shielded cell, the reverse breakdown voltage of the same cell increases by 1kD. If it is less than 9V, it will be destroyed.

In order to solve this problem, as shown in Fig. 1, there is a means to connect protection diodes (2) in antiparallel to each cell (1) connected in series. A configuration has been proposed in which a solar cell is provided with a protection diode. This conventional configuration, as shown in Figure 2,
Diodes with opposite directions are formed on the same substrate (3), one with a larger area is used as a photodiode and the other with a smaller area is used as a tb solar cell (1), and the other with a smaller area is used as a protection diode (2). The lead wires (4) are connected in antiparallel to each other so that the surface of the protective diode (2) is covered, thereby realizing the circuit shown in Figure #I1. In this case, the photodiode is connected to the optical layer ale from the surface side.
The s-type layer (tLp-type layer IO, each amorphous layer is formed in order so that light can enter from the surface side, and the protection diode is formed from the surface side by forming the opposite Fcp-type layer aυ, l-type layer Da
Each amorphous layer of the ta-type layer 0 is formed in order to form the lead l! (4)) It is designed to block the incidence of light from the surface side.

Therefore, in the structure of this conventional amorphous solar cell with a built-in protection diode, p-1-1 type and n-
The l-p type amorphous layer and the amorphous layer must be formed separately in two steps, which has the disadvantage that the manufacturing process becomes complicated.

[Summary of the invention]

In view of these conventional drawbacks, the present invention is designed to simultaneously form both a photodiode and a protection diode on the same substrate, instead of using the manufacturing process of a multilayer solar cell.

[Embodiments of the invention]

Hereinafter, one embodiment of the amorphous solar cell according to the present invention will be described in detail with reference to FIG. 3.

In the embodiment shown in FIG. 3, the solar cell (1) consisting of a photodiode has three amorphous layers of "+" sP type from the front side: bai, oa, oυ, (c),
(2), CI! 1), a1, and aυ are sequentially laminated, and as is well known, this multilayer structure cell divides the light-absorbing layer according to wavelength, and the photovoltaic cell as a whole is divided into two layers. Improves conversion efficiency. On the other hand, for the protection diode (2), correspondingly each p, i, n type amorphous layer 0υ, (to), a
3 are sequentially stacked, and these are simultaneously formed on the same substrate (3).

Next, a manufacturing process that enables simultaneous molding in this manner will be described. First, on the same metal substrate (3), a p-type amorphous layer a1 on the cell (1) side is formed by plasma CVD using a first mask.
Then, using the same mask, a type 1 amorphous layer aa on the cell (1) side is grown in the same manner. Subsequently, the mask is changed to a second mask, and n-type amorphous layers a3 on the cell (1) side and the diode (2) side are grown simultaneously. Therefore, this mask changing process is not difficult. In other words, for example, when using a multi-chamber separation growth apparatus that uses dedicated reaction chambers for each layer growth, a mask may be fixed in each reaction chamber, and the moving substrate may be set in this direction. Bye. From the above step, the first mask is again used to form the p-type amorphous layer υ of the cell (1), and then the second mask is used to form the l-type amorphous layer (2) of the cell (1) and the diode (2). , and then return to the first mask to form the n-type amorphous layer (to) of cell (1).
, put the cell (1) and diode (2) back into the second mask.
Grow the p-type amorphous layer 0υ of , the 1-type amorphous layer (end) of cell (1) by returning to the first mask, and finally the dynamic amorphous layer (end) of cell (1) using the same mask. By exchanging the masks in the middle of manufacturing in this way, it is possible to simultaneously place the desired solar cell (1) and protection diode (2) in antiparallel on the same substrate. ■- It is possible to connect.

In addition, in FIGS. 3 and 3 showing the above embodiment, there appears to be a large difference in the thickness of both diodes (1) and (2), but in reality, even on the cell (1) side, the thickness is The lead is only about 1 micron at most, and is the same as the conventional example in Figure 2 above! ! There are no problems with the connection.

〔Effect of the invention〕

As described in detail above, according to the present invention, from the first surface side, n*
In an amorphous solar cell in which a solar cell is constructed by laminating one set of 1sP type three-layer amorphous layers into at least three sets of multilayers, when forming a cell by stacking each set of AeP layers on a substrate, the same Simultaneous K n on the substrate
, j, and p layers to form a protection diode consisting of three amorphous layers of Pe's'' type in antiparallel, and the protection diode is built into the solar cell, so it can be used as usual. A desired amorphous solar cell can be obtained through an extremely simplified manufacturing process, and it has the advantage of helping to reduce costs as a solar cell module.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing the connection between a general solar cell and a protection diode, Figure 2 is a cross-sectional schematic diagram showing the configuration of a conventional amorphous solar cell with a built-in protection diode, and Figure 3 is a schematic cross-sectional diagram showing the configuration of a conventional amorphous solar cell with a built-in protection diode. FIG. 1 is a schematic cross-sectional view showing the structure of an amorphous solar cell incorporating a protection diode according to an embodiment of the invention. (1)...Solar cell, (2)...Protection diode, (3)...Substrate, (4)...Lead wire, aυ, Qυ, C1υ...p Shape amorphous m, a
s, (company), 6be...L-shaped amorphous layer, 餞, @
, a3... Mouth-shaped amorphous layer. Mr. Oiwa 1st year Figure 1 Figure 2 Figure 3 Procedural amendment (spontaneous) 1. Indication of the case Patent Application No. 16/1988 ffil 1 2. Name of the invention is Amorphous Tai II Den. 3. Person making the amendment Representative Hitoshi Katayama 4, Agent 5, Subject of amendment (1) Claims column of the specification (2) Detailed explanation of the invention column 6 of the specification, Contents of amendment (1) Specification The claims of the book are amended as shown in the attached sheet. (Add the following sentence after "There is no problem." on page 6, line 9 of the same book.) "In addition, in this example, the solar cell (1) is It was assumed that amorphous layers were laminated, but from the surface side p, i, n
The protection diode (2) can be simultaneously formed on the same substrate using the same method in terms of shape. ” (3) On the 12th line of the same page in the same book, after “p-type” there should be “or p,
Add "i, n type". As claimed above, an amorphous layer in which a second conductivity type layer, an i layer, and a first conductivity type layer are sequentially formed from the amorphous surface side of a set of eight layers in which conductivity type layers are sequentially formed is formed on the substrate. An amorphous solar cell characterized by polarized protection diodes.

Claims (1)

[Claims] A set of three amorphous layers of n, l, and p type from the surface side,
Furthermore, in an amorphous solar cell in which at least three sets of multilayers are stacked to form a solar cell, n
, 1. At the time of cell formation by multilayer stacking of each set of p layers, icn, 1. Individually select each layer of p to
An amorphous solar cell characterized in that protection diodes made of three amorphous layers of , i, and n type are formed in antiparallel.