JPS59182578A - Manufacture of photovoltaic device - Google Patents

Abstract

PURPOSE:To improve an optical utilization rate, and to automate a manufacturing process by removing the unnecessary sections of each layer in the adjacent space sections of a conversion region by the irradiation of energy beams. CONSTITUTION:A substrate 1 is arranged into a first electrode forming chamber, on the surface thereof a first electrode layer 2 is formed. The substrate 1 is moved into a gas reaction chamber forming a semiconductor layer to the substrate 1 by a gas reaction through a first preparatory chamber to which an evacuating means is related. A second electrode layer 4 is laminated and applied on the semiconductor layer while the unnecessary sections 3', 3' of each layer in the adjacent space sections 6ab, 6bc of a photoelectric conversion region are removed by the irradiation of energy beams. Accordingly, an optical utilization rate is improved while the automation of a manufacturing process is promoted.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a method for manufacturing a photovoltaic device that directly converts light energy into electrical energy.

(b) Prior Art Among photovoltaic devices of this kind, those using an amorphous semiconductor layer formed by a gas reaction, such as amorphous silicon, as a photoactive layer are already known.

Figure 1 shows a basic photovoltaic device using the above amorphous semiconductor layer, in which (1) is a transparent and insulating substrate, (2a), (2b), and (20) are on the substrate (1). A first electrode layer consisting of a transparent conductor such as tin oxide, indium tin oxide, etc. deposited at regular intervals on
(3C) is an amorphous semiconductor layer superimposed on each first electrode i ('2a) (2b) (2C) by glow discharge in a silicon compound gas, (4a) (4b) (4c).
) are each amorphous semiconductor layer (aa) (3b) (3c)
The superimposed wave M is applied to the first electrode layer (2b) on the right side (
20) is a second electrode layer made of a metal such as aluminum and bonded in its entire width direction.

Each of the amorphous semiconductor layers (3a), (31), and (30) is formed by adding, for example, a gas pouch or an impurity gas containing an N-type determining impurity to the inside of the amorphous semiconductor layer (3a), (31), and (30). The first electrode layer (, 2a) (2'b) (2C), the amorphous semiconductor layer (3a) (3'b) (30) and the second
Photoelectric conversion regions (5a) (5b) (5 (1) are light irradiated, each photoelectric conversion region (5a) (51)) (5 (1 is light irradiated), each photoelectric conversion region (5a) (51)) (5 (1 Generates an electromotive force, and the photovoltaic force is transferred to the first electrode layer (2'b)
(20) and the second electrode layer (4a) (4b) are added in series.

A photovoltaic device equipped with a semiconductor layer formed by such a seed gas reaction has superior productivity compared to a device made of a single crystal substrate obtained by slicing a single crystal produced by normal pulling into wafer shapes. As is well known.

The prior art disclosed in JP-A-55-125681 discloses a first electrode forming chamber, a gas reaction chamber, and a second electrode in which a first electrode layer, an amorphous semiconductor layer, and a second electrode layer are integrally arranged. By sequentially feeding the substrates into the formation chamber one by one, a plurality of photoelectric conversion regions are continuously formed on the substrate, and the excellent productivity of this lightning photovoltaic device as described above is effectively utilized. It was used.

In a photovoltaic device, one factor that influences the light utilization efficiency is the photoelectric conversion area (5a) (5b) (5C) that actually contributes effectively to photoelectric conversion with respect to the light receiving area of the entire device.
This is the percentage of the total area of However, the adjacent interval portions (6ab) (of each photoelectric conversion region (5a) (5bl (5C))
6bc) The ineffective region that does not contribute to photoelectric conversion, which inevitably exists in the area, reduces the above-mentioned area ratio.

Therefore, in order to improve the light utilization efficiency, first the first electrode layer (
, 2a) (2b) (20), and similarly the amorphous semiconductor m(3a>(3t+)(3t+)
C) and the adjacent spacing between the second electrode layers (4a), (4b), and (40) must be reduced.

However, although the above-described prior art has excellent productivity, by covering the adjacent spacing portions (6, ab) (abc) with a metal mask when each layer is deposited, the adjacent spacing where each layer is not deposited is reduced. Since the portions (6ab) (6bc) are directly formed and a well-known mask technique is used, it is not suitable for reducing the distance between the adjacent spaced portions (6abH6b'c). In particular, when a semiconductor layer is deposited by a gas reaction, the substrate (1) is kept at a high temperature during the reaction.

As a result, the adhesion between the metal mask and the metal mask is impaired due to a difference in coefficient of linear expansion, etc., and as a result, reaction gas flows around, which has an adverse effect on the above-mentioned reduction in the distance. In such prior art, a semiconductor layer deposited by a gas reaction lζ is not divided at an adjacent interval (6abt (abc)) but is commonly applied to a plurality of photoelectric conversion regions (5a) (5-o) (5C). The reason why it is a single piece that spans over each other is probably due to the reasons mentioned above.

(c) Purpose of the Invention The present invention has been made in view of the above points, and its purpose is to increase the efficiency of light utilization, as well as promote automation of the manufacturing process and further increase productivity. An object of the present invention is to provide an improved method of manufacturing a photovoltaic device. .

B) Structure of the Invention In the method for manufacturing a photovoltaic device of the present invention, a substrate having an insulating surface is placed in a first electrode forming chamber in which a first electrode layer is formed on the surface thereof, and after the first electrode layer is formed, an exhaust means is provided. The semiconductor layer is transferred to a gas reaction chamber formed by a gas reaction through a first preliminary chamber associated with a semiconductor layer, the semiconductor layer is laminated on the first electrode layer, and then a second preliminary chamber is associated with an exhaust means. Then, the second electrode formation chamber for forming the second electrode layer is moved, and the second electrode layer is laminated and deposited on the semiconductor layer, and unnecessary parts of each layer are removed in the adjacent spacing between the photoelectric conversion regions. The structure is such that it is removed by irradiation with an energy beam.

(E) Embodiment Figure 2 shows a manufacturing apparatus for carrying out the method of the present invention.
The figure shows the main parts, and Figures 4 to 9 show the states in each process. First of all, the second
The manufacturing apparatus shown in the figure will be explained with reference to FIGS. 4 to 9. The dish is a first electrode formation chamber in which a first electrode layer (2) is formed on the entire surface of the substrate (1), and 111 is a plurality of photoelectric conversion regions (5a) (5t)) (adjacent spaced parts (6a) of 5C). 'b)(abC)+The second laser chamber p in which the unnecessary part (21') of the first electrode layer (2) at this point is removed by irradiation with an energy beam, for example, a laser beam (LB) will be described later. a first preliminary chamber with associated exhaust means and a semiconductor layer, for example an amorphous semiconductor layer (3);
A gas reaction chamber in which unnecessary portions (21 (2') are removed and divided into plural first electrode layers (2a), (2b, and (2C)) are deposited by gas reaction so as to cover the entire surface, and I is an exhaust means to be described later. A second preliminary chamber, 05) associated with the amorphous semiconductor layer (3) is a second laser chamber, (16
) is a plurality of divided amorphous semiconductor layers (3a) (31)) (30) in which unnecessary portions +31'+31' have been removed and a second electrode formation chamber (1) in which a second electrode layer (4) is formed on the entire surface;
7+ is the unnecessary part of the second electrode layer (4) +41'+41'
In the sixth laser chamber, the first electrode forming chamber 0I to the sixth laser chamber α7 are removed by irradiation with a laser beam (LB).
Once the substrate (1) is transported, they are integrally connected via a transport means decoy. (19a) and (19b) are freely openable and closable entrance and exit doors provided at the entrances and exits of the first electrode forming chamber 00) to the third laser chamber α'71;
(20g) is for each chamber 001~(171 partition wall (21a)~
(21g) These are the first to seventh separation doors provided.

Figure 6 shows the conveyance mechanism of the substrate (1).
) is set in a frame-shaped tray @ with the surface on which each layer is formed (i.e., the bottom surface in this example) exposed,
The d tray (support) consists of a pair of chain belts (23a) (23b)... and the chain belt (23a) (23b) arranged in parallel.
3a) (23b) - driving wheels (24a) (2
41))... The aluminum entrance door (19a), the first to seventh separation doors (20a) to (20g), and the exit door (19a) are placed in an open state on a conveying means 081 consisting of... It passes through and moves from each chamber (1o) to the mouth and outside. for example,
As shown in Figure 3, the board (1) set on the tray @
is the chain bell l-(23a) (23
Stepped portions (25a) (25t) provided on the opposing portions of b)
Passing through the entrance door (19a), which is placed on the
The tray (22) is connected to the first electrode forming chamber (101) by chain belts (23a) (23b) provided in the first electrode forming chamber (101).
It is incorporated into σ.

The substrate (1) taken into the first electrode forming chamber (1o) is formed into a first electrode layer (2) with a thickness of 2,000 to 5,000 layers by electron beam evaporation using a transparent conductive material as a target.
is formed on the entire surface as shown in FIG. In this manner, the entire surface of the substrate (1) on which the first electrode layer (2) is formed is separated from the first electrode forming chamber 0α and the first looser chamber (111) by chain belts (23a) (23b). bulkhead (21i
), the entrance door (19a
) and into the first electrode forming chamber 4101, the chain bell is taken into the first looser chamber (111) through the first separation door (2OA) in the open state. l-(23a') (23b)... is each room (
Although the substrate (1) is divided into 1o) to αη, it is possible to continuously move the substrate (1) through the tray (2).

In the second laser chamber 111), the transported substrate (1) is imaged by a video camera (c), and when it reaches a predetermined position, the chain belt handle a') (23b) The drive wheels (24a), (24b), etc. are stopped, and the substrate (1), together with the tray (22), is fixed to an XY stage that moves in the X-axis and Y-axis directions. More specifically, the XY stage (support) has a control circuit (5) including a detection circuit that detects that the substrate (1) has reached a predetermined position.
) control signal CT L, XY stage (support)
The drive mechanism (30) that drives the
Lower the stage tracks and use the locking pieces (28a) (28b)
. . . Then, the tray 22) is held, and then the XY stage □□□ is raised to the irradiation position. When the substrate (1) is fixed to the XY stage area at the irradiation position in this way, the control signal CT L2 is output to the control circuit based on the position information obtained from the imaging of the video camera, and the laser device 0υ is Controls oscillation operation. The υ of such a laser device is a YAG with a Q switch with a wavelength of 1.06 μm.
A laser is used and the beam diameter is adjusted to obtain an average power of about 1 W through an optical lens OaI with a pulse repetition frequency of 3 KHz. The substrate (1) to which the laser beam (LB) is irradiated is moved approximately 50 zz by the XY stage □□□ based on the movement pattern stored in advance in the control circuit C (2).
Adjacent interval Q (6ab) scanned two-dimensionally at a scanning speed of /Sec and irradiated with the laser beam (LB)
The unnecessary part +21' (2) in (6be) is removed as shown in FIG. 2a)
(2b) (2C) (7) Spacing width is approximately 100μm
is set to

Such a laser beam (unnecessary part +2 due to LBH)'+2+
' Removal itself is well known as disclosed in Japanese Patent Application Laid-Open No. 57-1256E3, and is extremely fine-fabricable and can improve light utilization efficiency.

When the laser beam (LB) irradiation is completed, the XY stage Tsutomu) is lowered and the substrate (1) is transferred to the tray (
22) to make the substrate (1) movable again. At this point, a predetermined process is carried out in the first electrode forming chamber (10) which is the chamber behind the next substrate (1).
Formation of the electrode layer (2) has been completed. Therefore, each room has 00
)~aη, a predetermined process is carried out in a continuous manner,
In the following explanation, only the processing for the first substrate (1) will be described.

Next, the substrate (1) is transferred from the second laser chamber [11] to the first preliminary chamber (12+).This preliminary chamber a'lJ is used to transfer the substrate (1) to the next chamber, the gas reaction chamber (la), and when closing it, it is filled with air. This is to prevent reaction gas from entering the gas reaction chamber (13) or from leaking into the atmosphere. ), an exhaust valve ■, and a vacuum pump (2) are associated with each other.That is, before the substrate (1) taken into the first preliminary chamber +12+ is transferred to the gas reaction chamber uJ, Then, in the preliminary chamber az, the sixth separation layer (21C) is opened while the exhaust means (the second minute door (211), which is maintained in a reduced pressure state by the operation of 3ω) is closed;
A gas reaction chamber in a reduced pressure state or a reduced pressure state containing a reaction gas (
131.

When the substrate (1) is transferred to the gas reaction chamber +13,
An amorphous semiconductor layer (3) made of amorphous silicon is formed by well-known glow discharge on the entire surface of the first electrode layer (2i) (2b) (2Q) from which the main part +21'f21' has been removed and divided, as shown in Fig. 6. to adhere to. Such a gas reaction chamber (
13), when forming a P-N junction parallel to the film surface from the substrate (1) side, gas switching valves (40a) (40'
b) First, silane (S'LH4) was added by controlling (400).
) gas cylinder 0]) and diborane (B2H6) gas cylinder containing P5-determined impurities @rikara Si, H4 and B
After introducing 2H6 and forming a P-type layer with a thickness of about 200 to 300 layers, the gas reaction chamber 03) was evacuated by opening the exhaust valve (2), and then a film thickness of 4000 to 6000 layers was formed using only S1-H4. PH3 is added to Sj-H4 from a phosphine (PH3) gas cylinder containing N-type impurities to form a film with a thickness of 200~5.
Stack N-type layers of about 00 people.

When stacking semiconductor layers of different conductivity types in this manner, it is preferable to separate gas reaction chambers (13) for each conductivity type as disclosed in Japanese Patent Laid-Open No. 114387/1983. In this case, the gas reaction time for forming the mold layer is longer than that for other P-type and N-type layers in proportion to the film thickness, so the type 1 gas reaction chamber is wider. A plurality of substrates (1) are processed simultaneously, and each chamber aω~(17+
It is structured so that all processing, including .

After depositing the amorphous semiconductor layer (3), the substrate (1) is taken into the second preliminary chamber 0IJ, which is in a reduced pressure state by closing the fifth separation core (21e) and opening the exhaust valve (b).
Before the fourth minute, the door (21d) is closed and the reaction gas leaked into the chamber is collected.

Next, the substrate (1) is transported to the second laser chamber (t51) and the adjacent portions (6a, 'b) of the amorphous semiconductor layer (3) are transferred to the second laser chamber (t51).
The unnecessary parts +31'+31' in (ebc) are removed by laser beam (LB) irradiation, and the amorphous semiconductor layer (3a) (3b) (30) is divided as shown in FIG.
is formed.

The interval width L2 between each layer is set to about 300 μm. What must be kept in mind during such laser processing is that the first electrode layer (2a) is placed under the semiconductor layer (3) to be removed.
) (2 b) (2 The laser output, repetition frequency, or laser wavelength is selected as appropriate.

When the laser processing is completed, the substrate (
1) is transported. In this second electrode forming chamber 06), for example, by heating an aluminum substrate (goods) with a heater 2 in a vacuum, a second electrode layer 4 made of aluminum is formed over the entire surface as shown in FIG. Vacuum deposited.

After forming the second electrode layer (4), the substrate (
1) is transported, and as shown in FIG.
)) In (6bc), the unnecessary part of the second electrode layer (4) +4
A laser beam (LB) is irradiated to remove 1'+41', and at the same time the second electrode layer (4a) (4b) Nc) is divided, the first electrode Jjl (2a) (2b) (2Q)
, 7% Lua 77, semiconductor layer (3a) (3b) (3Q),
The photoelectric conversion regions (5a), (5b), and (5c) consisting of the second electrode layers (4a, 4b, and 4) are electrically connected in series. Adjacent interval width L3 of divided second electrode layers (4a) (4b) (4C)
is set to about 20 μm.

In this way, a plurality of photoelectric conversion regions (
When the board (1) in which 5a, 5b, and 5c are electrically connected in series is carried out from the exit door (19'D),
A photovoltaic device capable of generating photovoltaic force has already been formed.

It should be noted that the various numerical values, materials, etc. mentioned in the above embodiments are merely exemplary, and it goes without saying that they can be changed as appropriate.

(F) Effects of the Invention As is clear from the above description, the present invention provides first and second auxiliary chambers that are associated with exhaust means before and after a gas reaction chamber, and also provides space between adjacent photoelectric conversion regions. Since unnecessary parts of each layer were removed by irradiation with energy beams, each chamber can be connected continuously, which not only increases light utilization efficiency but also promotes automation of the manufacturing process and increases productivity. This can be further improved.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the main parts of a basic photovoltaic device, FIG. 2 is a schematic diagram of a manufacturing apparatus for carrying out the method of the present invention,
Figure 3 shows the main parts, and the same figure [AI is a side view, the same figure (
Bl is a top view, the same figure (C1 is the same figure (C-0 in Bl)
7-line sectional view, the same figure (DJ is the same figure (DD' in Bl)
A line sectional view and FIGS. 4 to 9 each show a step-by-step side view of a photovoltaic device manufactured by the method of the present invention. (1)...Substrate, [21(2a)(1)(2c)--
・1st @ polar layer, f31 (3a) (3b) (3C) ・-
M Lua As semiconductor layer, f41 (4a) (4b
) (4c)--second electrode layer, (5a)(5b)(
5C)...Photoelectric conversion area, (101...First electrode formation chamber, 01) (151071...First, second, and third laser chambers, Port 2041...First and second preliminary chambers ,03)・
...Gas reaction chamber. Applicant Sanyo Electric Co., Ltd. Agent Patent Attorney Shizuo Sano! Part 6

Claims (1)

[Claims] (1) A photovoltaic system in which a plurality of photoelectric conversion regions each consisting of a laminate of a first electrode layer, a semiconductor layer, and a second electrode layer are formed on an insulating surface of a substrate, and the photoelectric conversion regions are electrically connected in series. A method for manufacturing a power device, wherein the substrate is placed in a first electrode forming chamber in which a first electrode layer is formed on the surface of the substrate, and after forming the first electrode layer, the substrate is passed through a first preliminary chamber associated with an exhaust means. A second step in which the semiconductor layer is moved to a gas reaction chamber formed by a gas reaction, the semiconductor layer is laminated on the first electrode layer, and then passes through a second preliminary chamber associated with an exhaust means to form a second electrode layer. The method is moved to an electrode forming chamber, and a second electrode layer is laminated and deposited on the □ semiconductor layer, and unnecessary portions of each layer in the adjacent spacing of the photoelectric conversion region are removed by irradiation with an energy beam. A method for manufacturing a photovoltaic device.