JPH0533833B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a film forming apparatus. For more details,
This is a film forming device used to form the semiconductor layer or back electrode of an amorphous silicon solar cell, and because it is equipped with a thin wire so that it is in close contact with the film forming surface of the substrate, it is possible to form a pattern at the same time as film forming. The present invention relates to a film forming apparatus that can perform a patterning process, eliminate the need for a patterning process, and thereby significantly reduce costs. [Prior Art and Problems to be Solved by the Invention] Conventionally, an amorphous silicon layer and a back electrode have been patterned using an energy beam such as a laser beam for integration. However, when laser patterning is applied to an amorphous silicon layer, the performance of the solar cell may deteriorate due to damage to the transparent electrode, and the contact resistance between the transparent electrode and the back electrode at the laser scribed portion may change over time (resistance There were problems such as an increase in Further, laser patterning of the back electrode is difficult to perform and has the disadvantage that stable production cannot be achieved. Therefore, other methods such as the etching method or the lift-off method have to be adopted, and in this case, there are other problems such as an increase in processing steps, an increase in manufacturing costs due to a decrease in productivity, and a decrease in yield. was occurring. Furthermore, in any of the above cases, patterning is performed after forming the amorphous silicon layer or the back electrode, which increases the number of steps and increases the manufacturing cost. In view of the above-mentioned points, an object of the present invention is to provide a film forming apparatus that can simultaneously perform a film forming process and a patterning process without deteriorating the performance of a solar cell. [Means for Solving the Problems] The film forming apparatus of the present invention is a film forming apparatus used for forming a semiconductor layer or a back electrode of an amorphous silicon solar cell, and includes a main body that houses a substrate, and a main body that accommodates a substrate. , comprising a means for fixing and positioning the substrate to the main body, and a plurality of thin wires provided on the film forming surface side of the substrate and to be substantially closely attached to the film forming surface of the substrate. . [Example] Next, a film forming apparatus of the present invention will be explained based on the drawings. FIG. 1 is a plan view of an embodiment of the film forming apparatus of the present invention before a substrate is set, and FIG. 2 is an enlarged sectional view taken along the line A-A of the film forming apparatus of FIG. 1 with a substrate set therein. be. Examples of the film forming apparatus of the present invention when applied to a plasma CVD apparatus will be described below.
The present invention is widely applicable not only to plasma CVD apparatuses but also to other film forming apparatuses such as sputtering apparatuses and evaporation apparatuses. In FIGS. 1 and 2, reference numeral 1 denotes a substrate made of, for example, plate glass, on which a semiconductor layer and a back electrode are formed. On this substrate, a transparent electrode made of tin oxide etc. is formed by CVD method etc.
Thereafter, the transparent electrode is patterned by laser scribing or etching. Reference numeral 2 denotes a CVD tray main body 3 that is attached to the main body of the film forming apparatus, and a plurality of thin wires 3 are stretched above the substrate 1 accommodating portion of the tray main body 2. The wire 3 has one end fixed to the tray body 2 and the other end fixed to the tension adjustment screw 8. Figure 2 shows the substrate 1 set on the CVD tray main body 2, with the substrate 1 set so that the film forming surface is on the wire 3 side, the back plate 4, the spring 5, and the back plate presser. 6 and a back plate holding jig 7, it is fixed and positioned on the tray body 2 and pressed against the wire 3. This pressing is performed using the elastic force of the spring 5, and thereby the wire 3 is kept in substantially close contact with the film forming surface. And wire 3
By bringing the film into close contact with the film formation surface, plasma CVD
Even in devices that involve a lot of turning, it is possible to obtain a pattern in which the transparent electrode surface is completely exposed. In the film forming apparatus of this embodiment, one end of the wire 3 is fixed to a tension adjustment screw 8, and the tension adjustment screw 8 is used to adjust the wire 3 before or after setting the substrate 1 on the tray body 2. By adjusting the tension, the adhesion between the wire 3 and the film-forming surface of the substrate 1 can be further ensured. The wire 3 plays the role of a kind of mask, and by selecting the wire diameter between 0.08 and 2.0 mm,
The pattern width can be adjusted as appropriate. The material of the wire 3 is not particularly limited, and may be plasma CVD,
Any material can be used as long as it can withstand film forming treatment such as sputtering. For example, piano wire of type A or B, nickel-titanium alloy wire, etc. are used. In addition, if sagging of the wire 3 due to heat during the film forming process is a problem, add weights for tension adjustment to all the wires, to each several wires, or even to each wire at the end of the wire. Attach it to
Thereby, it is also possible to keep the tension of the wire 3 constant. Furthermore, by incorporating a spring into the adjustment screw, the tension of the wire 3 can be maintained within a certain range. Although the plasma CVD apparatus has been described above, it is possible to carry out the same method in a sputtering apparatus, which is also a glow discharge apparatus, as described above. In addition, in the vapor deposition apparatus, there is little wraparound of the film, and the same method can be used satisfactorily. Next, an example will be shown in which a film was formed and patterned simultaneously using the film forming apparatus of the present invention. Example 1 A 6000 Å tin oxide transparent electrode was provided on a blue plate glass with a thickness of 2.0 mm and a size of 150 mm x 440 mm, and this transparent electrode was separated into a predetermined pattern using a laser beam. The substrate 1 on which the pattern was formed in this way was fixed to the CVD tray 2 shown in FIG.
The substrate 1 was positioned using substrate positioning jigs 9 at four locations. Thin wire 3 is 17 in total
A type B piano wire with a wire diameter (diameter) of 0.3 mm was used. Note that before fixing the substrate 1 to the CVD tray 2, the tension of each wire was adjusted using the tension adjustment screw 8. FIG. 2 shows a state in which the substrate 1 is fixed. The CVD tray 2 with the substrate 1 fixed is placed in a plasma CVD device, and the substrate temperature is 130°C and the pressure is
p-type amorphous silicon carbide at 150 Å at 1.0 Torr, substrate temperature 180℃, pressure 0.5 Torr
Type amorphous silicon at 6000 Å, substrate temperature 180 Å
N-type microcrystalline silicon at 300 °C and 1.0 Torr pressure.
A was formed. After that, take out the CVD tray and
The substrate was removed from the tray and the portion masked by the wire was observed. Although some amount of wraparound was observed for each of the 17 separation lines that separated the semiconductor layers, no wraparound that could affect the performance of the resulting device was observed. Using a precision projector, the minimum pattern width was measured for each separation line in the part where the transparent electrode was completely exposed. The results are shown in Table 1.

[Table] Note that the distance between the end of the pattern line of the transparent electrode and the end of the separation line of the semiconductor layer closer to the transparent electrode pattern line was about 150 μm. The semiconductor separation substrate thus obtained was fixed on a sputter tray of the same type as in FIG. 1 with the semiconductor side facing the wire. In this sputter tray, each of the 17 wires was arranged at a position shifted by 0.25 mm in the perpendicular direction with respect to the wire shown in FIG. Furthermore, the wire diameter was set to 0.2 mm.
Note that before fixing the substrate to the sputter tray, the tension of each wire was adjusted using the adjustment screw. Next, place the tray with the substrate set in a magnetron sputtering device, and apply Ar pressure to 6×
Adjusted to 10 ^-3 Torr, substrate temperature 80℃, 5000Å
Al was formed to a thickness of . Thereafter, the substrate was taken out, and the Al separation line on the back electrode was measured using the method described above. Table 2 shows the minimum pattern width of the portion where Al is masked and the semiconductor layer is completely exposed for each separation line.

[Table] As shown in Table 2, there were no parts where the back electrode was incompletely separated, and good results were obtained. The performance of the solar cell obtained in the above manner is
Measured using a pulse simulator approximating AM-1.5. The results are shown in Table 3.

[Table] Comparative Example A substrate patterned with transparent electrodes in the same manner as in the example was set in the same CVD tray as in Fig. 1 except that the thin wires were not arranged, and almost the entire surface was coated with the example. A semiconductor layer was formed under the same conditions as above. Separation of the semiconductor layer was performed using a YAG laser. In addition, for Al sputtering, a thin wire was not used, but a back electrode was formed on almost the entire surface under the same conditions as in the example, and then the Al
The separation was carried out by chemical etching. The performance of the obtained solar cell was measured in the same manner as in the example. The measurement results are shown in Table 3. [Effects of the Invention] As explained above, when forming a film such as a semiconductor layer using the film forming apparatus of the present invention, there is no need for patterning using a laser or the like, so deterioration in the performance of solar cells can be prevented, and the production speed can be improved. Since the film process and the patterning process can be performed at the same time, the process is simplified, and the manufacturing cost of the solar cell can thereby be reduced.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the film forming apparatus of the present invention before a substrate is set, and FIG. 2 is an enlarged sectional view taken along the line A-A of the film forming apparatus of FIG. 1 with a substrate set therein. be. Main symbols in the drawing: 1...Substrate, 2...CVD tray,
3...Wire, 8...Tension adjustment screw.

Claims (1)

[Claims] 1. A film forming apparatus used for forming a semiconductor layer or a back electrode of an amorphous silicon solar cell, which comprises a main body that accommodates a substrate, and a substrate that is fixed to and positioned in the main body. 1. A film forming apparatus comprising: means; and a plurality of fine wires provided on the film forming surface side of a substrate and to be brought into substantially close contact with the film forming surface of the substrate. 2. The device according to claim 1, further comprising a mechanism for adjusting the tension of the wire. 3. The device according to claim 1 or 2, wherein the wire has a wire diameter of 0.08 to 2.0 mm.