JPS59177921A - Adhesion of film - Google Patents

Abstract

PURPOSE:To enable to make a mask to be adhered closely and to cover the surface of an insulating substrate even in a heated condition, to enable to prevent a film from oozing at the edge part, and to contrive to enhance precision of a process by a method wherein a material having nearly the same coefficient of linear expansion is used as a mask to cover the surface of the insulating substrate. CONSTITUTION:One main surface of an insulating substrate 10 manufactured of transparent glass is covered with a mask 11 having nearly the same coefficient of linear expansion with the substrate 10. First electrode layers 13a, 13b, 13c consisting of a transparent oxide electrode material of SnO2, In203-SnO2, etc. patterned in the previously decided pattern are adhered according to electron beam evaporation on the insulating substrate 10 through opening parts 12a, 12b, 12c dug in the mask 11. The temperature of the substrate at this time is held to the degree of 300 deg.C to obtain the desired transparency.

Description

[Detailed description of the invention] (b) Industrial application field The present invention relates to a method of depositing a film using a mask.

(b) Conventional technology The semiconductor film deposited on the surface of the substrate is large-area C, which is not suitable for semiconductor substrates.Since it is suitable and has excellent manufacturability, its use has rapidly increased in recent years. It is developing.

An example of a device using such a semiconductor film is a photovoltaic device that requires a large area, a so-called solar cell.

FIG. 1 shows the photovoltaic device described above, in which (1) is an insulating substrate made of glass or transparent plastic, (2a) (21))C
20) is the main surface C of the insulating substrate (1): a plurality of photoelectric conversion regions arranged in parallel, the conversion regions (2a) (2b) (2Q
) is oxidized from the insulating substrate (1) side;
02), indium tin oxide (Inz05-8nO2)
The first electrode film (5a) (3'b) (
3c) and, for example, an optical semiconductor film (4a) (41)) such as amorphous silicon having a PIN junction from the light incidence side.
40), the optical semiconductor film (4a) (4b) (40) and O! .

Aluminum AI that comes into contact with the robot! The second electrode film (51L
)(51))(5C) are sequentially stacked to form a laminated structure. Furthermore, the above-mentioned parallel photoelectric conversion regions (2
a)(21))C2Q) is the optical semiconductor film (4b) on the right
C40) The exposed part (6) (!IC') of the first electrode film (51)) C5Q) exposed on the insulating substrate (1) from the bottom surface is covered with the adjacent optical semiconductor film (4a) (41)) on the left. The extension part (5) of the second electrode film (5a) (51)) extending from the upper surface
a′)(51)′) are directly coupled, and thus the plurality of photoelectric conversion regions (2a)(21))(20) are electrically connected in series.

In such a device, one factor that affects the light utilization efficiency is the light receiving area (i.e. substrate area) of the entire device.
Actual power generation C″--contributing photoelectric conversion area (2a) (21)
) (20) is the proportion of the total area. However, the separation regions that inevitably exist at adjacent intervals between the photoelectric conversion regions (2N), (21), and (20) reduce the above-mentioned area ratio.

Therefore, in order to improve the light utilization efficiency, it is necessary to reduce the separation region, which is the interval between adjacent photoelectric conversion regions (21L), (21), and (20).

Such a reduction in the spacing is determined by the processing accuracy of the six films, and therefore, photolithography, which has excellent precision processing properties, is promising. In the case of this technique, the first electrode film is deposited on the entire surface of the substrate (1), and the individual first electrode films (31L), (31), and (50) are separated by photoresist and etching. 1 electrode films (3a) (311) (30), and then the same deposition and removal steps are performed on the optical semi-semiconductor films (4a) (41)) (40) and I
Jj & 2 electrode films (5tL) (5'b) (5c) will also be turned over again.

However, since the photo-etching technique described above includes a process such as washing with water, the photo-semiconductor film (4a) (4b) (4C
), and the second electrode material deposited in the next step reaches the first electrode film (3a) (3b) (30) through the pinhole. The first
The electrode films (3a) (3'b) (3c) are the photoelectric conversion regions (21L) (2b) (20) (7) and the optical semiconductor films (4a).
) (4'b) (4C) and the second electrode film (5
a) (511) and (50) caused an electrical short circuit accident.

Further, the contact surfaces of the optical semiconductor films (4a) (41)) (40) with which the second electrode films (5a) (51)) (50) come into Ohmig contact are coated and peeled off with photoresist using the photolithography technique described above. Even if no bottles are formed during washing, the film quality deteriorates, and a small amount of the water used for washing remains, causing the second electrode film to be deposited in the next process.
5a) (5b) (5o)v There was a risk of corrosion.

On the other hand, during the process of depositing six films without using photo-etching technology, the surface to be applied is covered with a mask and the film in a predetermined pattern is formed through the openings made in the mask. Direct deposition mask technology also exists, but although such mask technology simplifies the manufacturing process, it is difficult to process the 7th part of the film, especially when depositing the film on a heated substrate surface. Because of the seepage, processing accuracy is poor and it is not suitable for reducing the spacing of this type of equipment.

1. Purpose of the Invention The present invention has been made in view of the above, and its purpose is to create a film that improves processing accuracy despite using mask technology that simplifies the manufacturing process. Providing a deposition method (there are two).

B) Structure of the Invention The method for depositing a film of the present invention includes covering the surface of an insulating substrate in a heated state with a mask having a coefficient of linear expansion approximately equal to that of the substrate;
The structure is such that a film such as a semiconductor film or an electrode film is deposited on the surface of the substrate through the opening of the mask.

-) Embodiment 2, 3, and 5 to 8 show Embodiment Z, which was applied to the manufacture of the present invention 7 photovoltaic device.
In the process, the main surface of the transparent glass insulating substrate (10) is covered with a mask 11 having a coefficient of linear expansion approximately equal to that of the substrate (00).
11, and the opening (12
a) (12b) (12C) Y through L”C above insulating substrate (1
) SnO2, In2O with a thickness of 2000-5000A patterned in a predetermined pattern on top! t-8n
A first electrode layer (13a) made of a transparent oxidized electrode material such as 02
(15b) (13c) are deposited by electron beam evaporation (FIG. 3). At this time, the substrate temperature is maintained at about 300° C. to obtain the desired transparency.

Here, it should be noted that the insulating substrate (IQ) is heated to about 300° C. and that the mask (Ill) is approximately equal to the coefficient of linear expansion of the substrate (10). That is, the conventional mask technology does not take into account the coefficient of linear expansion between the substrate αQ and the mask CLfJ, for example, the coefficient of linear expansion is 8.
170X'10 for a soda lime glass insulating substrate (10) of 0X10-7 to 110X10
A metal mask OD made of stainless steel or the like with a size of -7 to 180 x 10-'/-C was used. Therefore, when the insulating substrate (10) is kept in a heated state, the mask aυ, which was in a state of tightly covering the surface of the insulating substrate (flo) at room temperature, becomes smaller than the substrate (10) as the temperature rises. As shown in the fourth rotation and tBl in the same figure, a (binary gap dy) is formed between the surface of the substrate (10).Such a gap d is , let α2 be that of the mask, T be the temperature difference, and 2L be the length of the expansion part.
It can be obtained approximately from the following formula C2.

Therefore, α+ = 80 x 10 /T, α2=
180X 10-'/C, T=300℃, 2L=
10 (1) (The gap d at 2 is approximately 4 tones. That is, as shown in FIG. Maximum about 4
A gap d of M is theoretically formed.

In this way, in the past, the parts to be covered were completely covered at room temperature! =However, when the film was deposited, a small gap d was formed, and as a result, the vapor flow went around the gap d, causing seepage in the etched part of the film that caused a decrease in processing accuracy. be.

That is, if a mask aυ made of a material with approximately the same coefficient of linear expansion is used as in this example, even if the insulating substrate (1
Even if [ is heated, the gap d is not formed and the mask a
υ continues to be tightly coated on the surface (2) of the insulating substrate (10) as at room temperature, and no seepage occurs in the etched portion of the film.The mask material used in this example is glass or Partially crystallized glass and glass/ceramics obtained by further crystallizing the partially crystallized glass are suitable, such as the product name "Photoform" from Corning Corporation;
"Photoform Opal" and "Photoceram"
It is sold as. The linear expansion of such a mask material is sequentially 84X1 [1-shi 89X10℃ 1G4
% is approximately equal to that of the insulating substrate (10) material.

Furthermore, the glass or glass-ceramic manufactured by Corning Co., Ltd. exhibits photosensitivity in which the rate at which acid C2 dissolves differs between the portions irradiated with ultraviolet rays and the portions not irradiated with ultraviolet rays. Since the mask pattern can be directly exposed without using photoresist as the mask material, accurate etching processing can be performed and a mask circle having a fine mask pattern can be obtained.

Next, in the process shown in FIG. 5, with only the left end of each first electrode film (15 凰) (13'b) (130) covered with a mask 2, an opening (15IL) is formed by a plasma reaction in a silane atmosphere. (151)) Semiconductor film made of amorphous silicon having a PIN junction with a thickness of about 5000A to 1μm through (150) (16&) (161))
(160) is applied (Fig. 6). Such a semiconductor film (16
&) (16b) In the deposition process of (16G), even though the insulating substrate ELL is held at approximately 300°C, the semiconductor film (1
6') (16'b) (160) No leaching or seeping occurs during the process.

In the final step in FIG. 7, the mask (17)
18a'b) (1131: lo) Exposed part (131) of the first electrode film (151)) (130) exposed at the knee
) (, 13Q') root part (13b") (13Q")
and the opening (19a) in a state where the end of the substrate α0 is covered.
(19'b) Thickness 5000A ~ 1μ via (19c)
The second electrode film (20 tL) (201
)) (20(1) is deposited by vacuum evaporation. Figure 8 shows the state after deposition. Although the substrate 0Q in this odor deposition process is not directly heated by a heat source, , Al
t Approximately 100 to 120"C1 due to heating and evaporation
=Temperature is rising.

In addition, in FIG. 7, the gap δ between the mask αη and the substrate (10) is drawn larger than the gap d due to thermal expansion of the mask (11) shown in FIG. However, in reality, the above gap δ is $1 electrode film (13") (13'
tl) (130) and semiconductor film (16 &) (161+) (
160), and is therefore about 1 to 2 μm, and as in the above example, there is a relationship of δ(d) with d, which is on the order of μm, and the gap δ is on the order of μm. is hardly a problem.

(f) Effects of the Invention As is clear from the above description, the present invention provides an insulating substrate surface V
Since the covering mask has approximately the same coefficient of linear expansion as the substrate, the mask can closely cover the surface of the substrate even in a heated state. Therefore, using mask technology that simplifies the manufacturing process. Despite this, seepage in the etched area of the membrane is still low! A can be stopped, the processing accuracy can be improved, and it is particularly useful for manufacturing photovoltaic devices.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the main parts of a basic photovoltaic device, and FIGS. 2, 3, and 5 to 8 are examples in which the present invention is applied to a method for manufacturing a photovoltaic device. Fig. 4 is a top view showing a conventional example, and Fig. 4 (Bl is a sectional view taken along line B-d in the same figure. 0.0) ... Insulating substrate , (11) (111 (141
(17)-? Sufu, (13 &) (151)) (13Q
)...first electrode film, (161L) (161) ) (
160)...Semiconductor film, (201(20'b)(2
00)...Second electrode film. Figure 1 Figure 2 O Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] (1) Covering the heated insulating substrate surface with a mask having a coefficient of linear expansion approximately equal to that of the substrate, and depositing a film such as a semiconductor film or an electrode film on the substrate surface through the opening of the mask. A film deposition method characterized by: