JPS62142368A - Manufacture of thin film semiconductor device - Google Patents

Abstract

PURPOSE:To omit a patterning process of a back surface electrode and to decrease man-hours in laser cutting machining, by ensuring the maintenance of an interval between a second electrode and a semiconductor layer in an adjacent region. CONSTITUTION:On the pattern of a surface electrode 2, which is formed on a glass substrate 1, an amorphous silicon layer 30 is formed. Thereafter, the amorphous silicon layer is cut into equal strip parts with YAG laser. At this time the laser light input direction 6 is set to that an incident angle of 45 deg. is provided with respect to the glass substrate 1 as shown by arrows 6. The shape of the cross section of a cutting region 7, which is shown by a shaded area in the amorphous silicon layer 30, is slanted by 45 deg. with respect to the substrate. Finally, aluminum is evaporated to a thickness of 300nm in an evaporating direction 5 so as to form a right angle with slant end surfaces 31 and 32 of divided amorphous silicon layer 3. Thus, the amorphous silicon solar battery can be manufactured without the laser cutting of a metal film.

Description

[Detailed description of the invention] [Technical part l'F to which the invention pertains]

The present invention relates to a thin film semiconductor device having a structure in which a plurality of thin film semiconductor elements are formed on the same substrate and are electrically connected.

[Prior art and its problems]

As a thin film semiconductor device of this type, an amorphous π silicon solar cell having a transverse cross-section as shown in FIG. 2 is conventionally known. This amorphous silicon solar cell has a transparent surface electrode 2 on a glass substrate 1. Amorphous silicon layer with pin junction3. Unit solar cells formed by laminating metal salt surfaces with poles 4 are arranged adjacent to each other, and by overlapping the extension of the front electrode 2 with the extension of the back electrode 4, the solar cells are connected in series. In this case, the range to is the valid originating area, and the range to B is the connection area. Such solar cells are manufactured through the following steps. First, a tin oxide (SnO□) film is formed to a thickness of, for example, 200 nm on a glass substrate l by a chemical vapor deposition method (CVD method). Next, using a YAG laser with a wavelength of 1.06 m, the tin oxide film is cut into strips of equal size, and on top of this, p-type, i-type, and n-type non-containing strips are cut. Crystalline silicon stores in order,
For example, it is deposited to a thickness of 10 nm, 500 nm or 450 nm by the well-known glow discharge decomposition method of silane gas (SiHa). Subsequently, the amorphous silicon layer is cut into strips of equal size using a YAG laser to form an amorphous silicon layer 3. At this time, it is necessary to control the output light energy density of the YAG laser and be careful not to damage the transparent surface bridge 2 under the cut portion, that is, not to change its electrical or chemical properties. Furthermore, aluminum (kl) is deposited on the entire surface by electron beam evaporation from the direction shown by arrow 5, and the aluminum film is cut into equal-sized strips using a YAG laser to form the back electrode 4. However, in the above-mentioned thick V4 battery, there is a drawback that the manufacturing cost is high because the cutting process using the YAG laser is performed three times. Furthermore, when laser processing the metal back electrode 4, it must be cut so that the transparent surface electrode 2 remains at the bottom, but if the thickness of the back electrode 4 to be cut is uneven, such a laser Another drawback was that it was difficult to control the cutting.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a thin film semiconductor device that eliminates the above-mentioned drawbacks, eliminates the need for a patterning process for back electrodes, and reduces the number of laser cutting steps.

[Key points of the invention]

According to the present invention, after a thin film semiconductor layer is deposited over the entire surface of a first electrode formed separately on a substrate, a part of the thin film semiconductor layer is removed in parallel lines and divided, and at that time, the removed portion is a semiconductor layer. The second electrode is formed by depositing metal so that it enters one side from the surface of the layer, and then from a direction tilted toward the side perpendicular to the substrate at the semiconductor layer dividing line. Because it is separated and formed without a cutting process,
The above objectives can be achieved.

[Embodiments of the invention]

Embodiments will be described below with reference to figures. FIG. 1 shows an embodiment of the present invention, and parts common to those in FIG. 2 are given the same reference numerals. Similar to the above process, the substrate l
After forming an amorphous silicon layer 30 on the pattern of the surface electrode 2 formed thereon, the amorphous silicon layer is cut into strips of equal size using a YAG laser.
A laser beam is applied to the glass substrate l from the direction indicated by the arrow 6 at an incident angle of 45 @, and the shape of the cross section of the cutting region 7 shown by diagonal lines of the amorphous silicon layer 30 is as follows. It was made to be inclined by 45"4'fM with respect to the substrate. Finally, as shown in 1r2I ('bl), the evaporation direction 5 which is perpendicular to the inclined end faces 31 and 32 of the amorphous silicon layer 3 was set. Aluminum was deposited to a thickness of 300 nII+. By doing this, the first layer was deposited without laser cutting the metal film.
It is possible to manufacture an amorphous silicon solar cell as shown in FIG.
Since the distance between and the cut surface 31 of the amorphous silicon layer is maintained and there is no contact between the back electrode 4 and the front electrode 3 in one effective power generation area 5^1 in the connection area B. Alternatively, the occurrence of a short circuit between the adjacent effective power generation area A2 and the electric field 4 is prevented. Note that in this example, the cross section of the amorphous silicon layer is
Although cutting was performed to form an inclined plane, it is clear that a separated back electrode can be formed by oblique vapor deposition if the cut is made so that the removed portion of the amorphous silicon layer enters one side from the surface. 2) As a method for cutting the amorphous silicon layer, a ruling engine, which is widely used to mechanically form grooves having arbitrary angles during the manufacture of diffraction gratings, may be used instead of the Yag laser. [Effects of the Invention] The present invention forms a first electrode laminated on a substrate, a second electrode separated from the yi film thickness conductor layer dividing region by diagonal metal vapor deposition without a cutting process, and By making the removal part for dividing the thin film semiconductor layer penetrate into one side from the surface, the second 1! The distance between the pole and the semiconductor layer in the adjacent region is reliably maintained. This results in an extension of the second electrode on the other side and the first one! Effects obtained because it is possible to reduce the number of cutting steps by one for manufacturing thin film semiconductor devices in which thin film semiconductor elements are connected in series by overlapping with the extensions of the poles with high reliability. is extremely large.

[Brief explanation of drawings]

FIG. 1(a) (mountain) is a cross-sectional view showing the manufacturing process of an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the conventional solar cell manufacturing method. 2: Light-transmitting surface electrode, 3,3O: Amorphous π silicon layer, 4: Back electrode, 5: Metal deposition direction, 6:
Laser beam incidence direction. τ7; "Hitoshiru +b XJ Q''-,. ・ ! Figure 1

Claims (1)

[Claims] 1) A first electrode, a thin film semiconductor layer,
When a plurality of thin film semiconductor devices are formed by laminating metal second electrodes and the extensions of the second electrodes are overlapped with the extensions of the first electrodes of adjacent devices to connect each device in series, A thin film semiconductor layer is deposited over a plurality of first electrodes that are formed separately, and then a part of the layer is removed in parallel lines to divide the layer. A method for manufacturing a thin film semiconductor device, characterized in that the second electrode is formed by vapor-depositing metal from a direction tilted toward the side with respect to a plane perpendicular to the substrate at the semiconductor layer dividing line. 2) Manufacturing a thin film semiconductor device according to the method according to claim 1, characterized in that part of the thin film semiconductor layer is removed by irradiation with laser light from a direction oblique to a plane perpendicular to the substrate. Method.