JP2003158078A - Method for forming silicon semiconductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming a silicon semiconductor film of a low crystal defect density at a high speed in order to obtain an amorphous silicon solar battery with less optical degradation conversion efficiency. SOLUTION: In forming an (i) layer amorphous silicon film to be a power generation layer, a substrate surface heating heater is arranged between a substrate disposed inside a reaction container and a ladder antenna electrode generating glow discharge plasma, a surface temperature of the substrate is controlled by heating the substrate surface heating heater while making a reactant gas composed of gaseous silane diluted in gaseous hydrogen flow into a reaction chamber, and the amorphous silicon semiconductor film is formed while heating the reactant gas. It is appropriate to turn a mixing ratio of the gaseous hydrogen and the gaseous silane to 1:1 to 10, preferably 1:2 to 7, and more preferably 1:3 to 5. In order to maintain a film formation speed, a super high frequency current of 30 to 100 MHz is used for a power source for plasma generation.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for manufacturing a silicon semiconductor, particularly an i-layer silicon semiconductor used for an amorphous silicon solar cell.

[0002]

2. Description of the Related Art Solar cells (photovoltaic devices) that can directly obtain electricity from the light of the sun are being put to practical use as new energy sources that are semi-permanent and pollution-free. Recently, research and development have been carried out focusing on how to efficiently convert sunlight into electric energy and how to reduce power generation costs. Among them, amorphous silicon (a-Si: amorphous silicon) solar cells have been attracting attention as mass-spread solar cells. Amorphous silicon solar cells are slightly inferior to crystalline silicon solar cells in terms of power generation efficiency, but plasma CVD (Chemical Vapor
por Deposition: suitable for mass production because it is manufactured by the chemical vapor deposition method, and it can be manufactured by a relatively low temperature process of about 200 ° C, so it consumes less energy for manufacturing and is not limited by the type of substrate. Therefore, it is most expected as a popular solar cell in the future.

FIG. 1 shows the basic structure of an amorphous silicon solar cell. As shown in FIG. 1, in an amorphous silicon solar cell, an intrinsic amorphous silicon film (hereinafter, referred to as i layer) 4 on a glass substrate 1 is a p layer amorphous silicon (hereinafter, referred to as p layer) film 3 and an n layer amorphous silicon (hereinafter referred to as p layer). Hereinafter, a semiconductor film 6 having a pin structure sandwiched between films 5 is provided, and a transparent electrode 2 and a metal electrode 7 for taking out a current are provided in the semiconductor film 6.
When sunlight is incident on such a laminated structure, an electron-hole pair is generated due to a photoelectric effect, and the electron-hole pair is moved to the n-layer side by an electric field formed inside the i-layer by a pin junction. , The holes move to the p-layer side. At this time, if an external load R is connected between the transparent electrode film 2 and the metal electrode film 7, a current flows through an external circuit to generate power.

As described above, in an amorphous silicon solar cell, since it is the i-layer that absorbs light to generate power, the film quality of the i-layer affects the power generation efficiency. Therefore, how to create a high-quality i-layer Is an important issue. In order to achieve sufficient conversion efficiency, the thickness of the i layer is usually several hundreds nm
Therefore, it is necessary to have several tens of times the film thickness of the p layer and the n layer (normally several tens nm). Therefore, in order to increase the productivity and reduce the cost, it is important to reduce the film thickness of the i layer as much as possible and increase the film formation rate as much as possible. However, if the film formation rate is increased, it becomes difficult to obtain a good quality semiconductor film. In recent years, the thickness of the i-layer has been gradually reduced,
I for absorbing sufficient light to generate electron-hole pairs
The layer thickness is usually about 300 to 600 nm.

Not all electron-hole pairs generated by the sunlight incident on the i layer contribute to power generation, and some of the generated carriers recombine and disappear. In particular, dangling bonds formed during the formation of the i layer serve as carrier traps, resulting in a decrease in output current. Therefore, it is necessary to form the i layer in which such crystal defects are minimized.
These semiconductor films 6 are usually formed by thermal CVD method or plasma CVD method.
Formed by the law. Further, in order to reduce crystal defects in the i layer 4, a method of adding a slight amount of hydrogen when forming the i layer 4 (see Japanese Patent Laid-Open No. 11-214717),
A method of providing a buffer layer between the p layer 3 and the i layer 4 to prevent diffusion of impurities from the p layer 3 (JP 2000-164A).
904) is known.

Further, the present applicant has previously adopted a ladder antenna type electrode as an electrode for generating glow discharge plasma in a plasma CVD apparatus, and heats the surface of the substrate between the substrate and the ladder antenna type electrode. Therefore, an apparatus for manufacturing an amorphous semiconductor thin film has been proposed, which is provided with a substrate surface heating heater composed of rod-shaped wires having a predetermined interval (see Japanese Patent Laid-Open No. 10-321525). Using such a device, the substrate surface temperature is precisely controlled by the substrate surface heating heater, and only long-lived and long-diffusion radicals generated in the process of plasma reaction gas such as silane (SiH ₄ ) are generated. By facilitating the deposition on the surface of the substrate, it becomes possible to form a high-quality silicon semiconductor film with few crystal defects with a crystal defect density of 10 ¹⁴ / cm ³ , and the amorphous silicon film thus obtained is used for solar cells. A high-performance solar cell can be obtained by using it as the i layer.

[0007]

However, even if a high-quality silicon semiconductor film with few crystal defects is formed using the above-mentioned device to form a solar cell, the so-called light conversion efficiency decreases with the passage of time. Deterioration occurs and the performance as a solar cell deteriorates. Therefore, further suppression of photodegradation is desired. Further, further cost reduction is required for the spread of solar cells, and it is necessary to increase the deposition rate of a high-quality silicon semiconductor film with few crystal defects to obtain a high-performance device with less photodegradation at high productivity. Is required. The present invention has been made in view of such circumstances, and since the photodegradation of an amorphous silicon solar cell is mainly due to the crystal defect density of the i layer, a silicon semiconductor having a further lower crystal defect density can be produced at a high speed. It is intended to provide a method of forming.

[0008]

In order to solve the above problems, the present invention provides a method for forming an amorphous silicon thin film on a substrate by plasma CVD vapor phase epitaxy,
A substrate surface heating heater is arranged between the substrate arranged in the reaction vessel and a ladder antenna type electrode for generating glow discharge plasma, while flowing a reaction gas consisting of silane gas diluted in hydrogen gas into the reaction chamber, A method for forming a silicon semiconductor, in which the substrate surface heating heater heats the substrate from the surface to precisely control the substrate surface temperature, and at the same time, the substrate surface heating heater heats a reaction gas to supply energy while supplying energy. It was adopted. In the present invention, it is suitable that the mixing ratio of the silane gas and the hydrogen gas as the reaction gas is 1 to 1 to 10, more preferably 1 to 2 to 7, and further preferably 1 to 3 to 5.

If such a method is adopted, energy can be applied to the precursor in the vapor phase during the film formation process of the silicon semiconductor film to sufficiently lengthen the diffusion length of the precursor, and an extra unbonded hand is used. It is possible to give a sufficient opportunity to bond hydrogen with hydrogen to suppress the incorporation of unbound bonds of the precursor into the silicon semiconductor film, and as a result, to form a high-quality silicon semiconductor film with a low crystal defect density. Can be obtained at speed.

In the method for forming a silicon semiconductor according to the present invention, it is preferable that the surface temperature of the substrate is controlled to 140 ° C to 220 ° C. Substrate surface temperature 140 ℃ ~ 22
In order to control the temperature at 0 ° C., it depends on the size of the substrate and the structure of the apparatus, but for example, the temperature of the substrate surface heating heater is set to 7 ° C.
It can be achieved by controlling at 5 ° C to 400 ° C. This is because if the surface temperature of the substrate is kept at an appropriate temperature, it becomes easy to obtain a good quality semiconductor crystal with few crystal defects.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The embodiments of the method for manufacturing a semiconductor device according to the present invention will be described below, but the present invention is not limited thereto. First, a semiconductor device manufacturing apparatus used in the present invention will be described. 2 to 4 are schematic views of a semiconductor manufacturing apparatus used in the present invention. Figure 2
FIG. 3 is a schematic sectional view showing the structure of a plasma CVD apparatus used in the present invention. FIG. 3 shows a schematic view of a substrate surface heater for heating the surface, which is arranged between the substrate used in the present invention and the ladder antenna type electrode. Figure 4
FIG. 3 is a schematic diagram of a ladder antenna type electrode used in the plasma CVD apparatus shown in FIG. 2. As shown in FIG. 2, a substrate heater body 13 having a heater 12 therein is arranged in the reaction vessel 11, and a substrate 14 placed on the substrate heater body 13 is directly attached to the substrate heater body 13. I try to heat it.

Further, the substrate surface heater 1 is provided between the ladder antenna type electrode 23 on the upper surface side of the substrate 14 in the figure.
5 is provided so that the substrate surface is heated from above the substrate 14. The substrate surface heating heater 15
As shown in FIG. 3, the heater is constituted by one wire in the same plane.
The wire heater 16 is formed by connecting a and the U-shaped heater portion 16b. The thickness (d) of the wire heater 16 used for the substrate surface heater 15 is 0.2.
~ 0.3 mm, the spacing (g) between the wire heaters 16 is 2 to 2
It is suitable to set it to 0 mm. Substrate surface heating heater 1
If 5 is configured in this way, an aperture ratio of 80% or more can be secured, so that the radical flow reaching the substrate surface is sufficient,
It is possible to eliminate the dependency of the deposition rate on the deposition time. Power supply lines 17a, 1 are provided on both ends of the wire heater 16.
Electric power is supplied from the substrate surface heating power source 19 via 7b and the current introduction terminals 18a and 18b. By using such a substrate surface heater 15, the temperature of the substrate surface can be controlled to an optimum temperature, and energy can be imparted to the radicals in the reaction gas, so that a semiconductor film with few crystal defects can be obtained. Can be obtained.

On the other hand, as shown in FIG. 2, a gas mixing box 20 is arranged on the upper side in the reaction vessel 11, and the reaction gas (SiH ₄ and H _{2 is} supplied from the outside through a gas introducing pipe 21.
Mixed gas) 22 is introduced. The gas mixing box 20
Has an opening 20a formed on the side of the gas mixing box 20 facing the substrate 14, and a ladder antenna type electrode 23 for generating glow discharge plasma so as to cover (or close) the opening 20a. Are arranged. The supplied reaction gas 22 is made into glow discharge plasma. As a result, all of the supplied reaction gas 22 passes between the ladder antenna type electrodes 23, and an efficient reaction becomes possible. The ladder antenna type electrode 23 is
As shown in FIG. 4, two rod-shaped frame members 24 and the frame members 24 are provided.
An electrode 23 is composed of a ladder-shaped ladder member 25 provided in a direction orthogonal to the power supply point 2 of the electrode 23.
6a and 26b are connected to the power supply lines 27a and 27b and the current introduction terminals 28a and 28b by the high frequency power source 29 and the impedance matching device 30 and the frequencies of 30 to 100.
Ultra high frequency power of MHz can be supplied.

The reaction gas introduction pipe 21 is used in combination with a reaction gas supply device (not shown) and the reaction gas mixing box 20, so that the reaction gas having an arbitrary dilution ratio and flow rate can be supplied to the ladder antenna type electrode 23. It is designed to discharge. The gas in the reaction container 11 is exhausted to the outside through a vacuum pump (not shown) through the exhaust port 11a.

Further, when a silicon semiconductor is manufactured using the above manufacturing apparatus, a thin film of, for example, amorphous silicon is formed on the surface of the substrate by glow plasma conversion of the reaction gas. Since the temperature greatly affects the physical property value of the thin film, it is important to monitor the temperature with a thermometer to control the substrate temperature. Here, as shown in FIG. 2, the substrate heater body 1
3 is used in combination with the heater 12 and the cooling pipe 31 arranged inside thereof, and the first thermometer (for example, thermocouple type thermometer) 32 installed inside the heater body in advance, The temperature of the substrate 14 described later can be controlled to an arbitrary value. The temperature of the surface of the substrate 14 is measured by a second thermometer (for example, thermocouple type thermometer) 33 installed in advance on the substrate surface.

As the power source for heating the substrate surface, a direct current power source, a commercial frequency power source (50 Hz, 60 Hz) and a power source having a built-in half-wave or full-wave rectifier can be appropriately used. In addition, since a high frequency (for example, 13.56 MHz) voltage (induction noise) induced by the electric field / magnetic field generated by the ladder antenna type electrode 23 is generated in the substrate surface heater 15, a high frequency voltage is generated. The induction noise is removed by interposing a high-frequency removal capacitor (for example, 600 pF at 13.56 MHz) 34 in the circuit grounding.

Next, a film forming method for producing a high quality amorphous silicon film using the apparatus shown in FIG. 2 will be described. Silane (SiH ₄ ) was added to hydrogen (H
Supply the diluted mixed gas to ₂ ). The mixing ratio of silane and hydrogen is 1 to 10 times (1 to 1 hydrogen for 1 silane).
0) is suitable. The mixing ratio of silane and hydrogen is preferably 2 to 7 times, more preferably 3 to 5 times. In the process of silicon film growth due to the decomposition of silane, a radical (precursor) in the vapor phase abstracts hydrogen on the growth surface, and another radical binds to the unbonded hand from which hydrogen has been abstracted to grow the film. There are two processes to do. Since the dangling bonds become crystal defects, it is important to surely bond the dangling bonds with radicals in order to obtain a semiconductor film with few crystal defects. The substrate surface heating heater is used to further give energy to the radicals after the decomposition of the raw material gas, thereby extending the diffusion distance of the radicals on the growth surface and making it possible to reliably bond with the dangling bonds. In addition, a large amount of hydrogen in the reaction gas exhibits an action of bonding with excess dangling bonds and leaving them as dangling bonds.

When the silane concentration in the reaction gas is lowered and the hydrogen concentration is raised, the effect of removing excess dangling bonds is obtained, but on the other hand, the film formation rate is lowered and the productivity is lowered. Therefore, the dilution ratio of silane and hydrogen has an appropriate range, and the mixing ratio of silane and hydrogen is 1 to 10 times, preferably 2 to 7 times,
More preferably, it is 3 to 5 times. When the mixing ratio of silane and hydrogen is less than 1 time, the crystal defect density in the formed amorphous silicon semiconductor cannot be lowered, and the mixing ratio of silane and hydrogen is 1 or less.
If it is diluted more than 0 times, it is not preferable because the film forming rate is lowered and the productivity is lowered. The supply amount of the reaction gas is about 500 to 800 sccm as the amount of silane gas, and the pressure is 0.03 to 1 Torr with a pressure gauge (not shown).
And

In order to obtain a good quality silicon film with few crystal defects, the substrate temperature during film formation is extremely important. It is necessary to control the temperature of the deposition surface of the substrate during film formation to 140 to 220 ° C. In the plasma CVD apparatus shown in FIG. 2, the substrate temperature is heated mainly by the substrate heater body 13 from the back side of the deposition surface to keep the substrate 14 at a high temperature, but a mixed atmosphere of silane and hydrogen of about 0.3 Torr is used. Among them, depending on the size of the silicon substrate, a temperature difference of about 30 ° C. occurs between the front surface and the back surface of the silicon substrate. Therefore, the temperature of the deposition surface of the substrate may deviate from the proper temperature, and a good quality silicon film cannot be obtained. In the present invention, the substrate is heated from the back side of the deposition surface, and at the same time, the substrate surface heating heater is used to heat the substrate from the deposition surface side of the substrate to precisely control the temperature of the deposition surface of the substrate.
For controlling the temperature of the deposition surface of the substrate, the plasma CV shown in FIG. 2 is used.
In the D device, the second thermometer 33 is used to
It can be precisely controlled in the range of 0 to 220 ° C. Depending on the size of the device, the surface temperature of the substrate should be 140-22
In order to control the temperature in the range of 0 ° C., for example, a high frequency current may be used to control the heater for heating the substrate surface at 75 to 400 ° C.

According to the method for forming a silicon semiconductor of the present invention,
Since silane gas diluted with hydrogen is used as a raw material,
As a result, the etching rate of hydrogen radicals lowers the deposition rate. In order to recover the decrease in film formation speed,
By increasing the frequency of the high-frequency current for generating glow discharge plasma and increasing the output, a film deposition rate of about 0.7 nm / sec, which does not hinder practical use, is secured from the conventional 0.27 nm / sec. Is possible. That is, as the frequency of the high frequency current, 13.56 MHz has been frequently used in the past, but in the present invention, an ultra high frequency current of 30 to 100 MHz can be used. In addition, the electric power applied to the ladder antenna type electrode for generating glow discharge plasma is about 0.04 W / cm ² to 0.2 W / c.
It can be increased to about m ² .

[0021]

EXAMPLES The present invention will be described more specifically with reference to the following examples and comparative examples. Example 1 A transparent electrode film made of SnO ₂ having a thickness of 700 is formed as a transparent electrode film on a glass substrate by using a thermal CVD apparatus.
The film was formed to a thickness of nm. Then, a semiconductor thin film of amorphous silicon having a pin junction structure was formed on the entire surface of the substrate by using a plasma CVD apparatus. The p-layer amorphous silicon film was formed by glow discharge decomposition using silane gas (SiH ₄ ), methane gas (CH ₄ ) and diborane gas (B ₂ H ₆ ) for p-layer impurity element doping. The film thickness was 15 nm. Then, the i-layer amorphous silicon film was formed using the plasma CVD apparatus shown in FIG. As reaction gas, silane (SiH ₄ ) 800 sccm and hydrogen (H ₂ )
A mixed gas of 2400 sccm was used. That is, the dilution ratio of silane to the hydrogen carrier gas is 3 times. Other film forming conditions were a substrate surface temperature of 170 ° C., a film forming pressure of 0.4 Torr, and an ultra high frequency current having a frequency of 60 MHz was applied to the ladder antenna type electrode at 0.2 W / cm ² . The substrate surface heating heater is formed by arranging heater wires having a wire diameter of 0.23 mm at intervals of 2 mm.
A high frequency current of Hz was applied at 0.35 W / cm ² . The deposition rate was 0.5 nm / sec, and the thickness of the i-layer amorphous silicon film to be deposited was 300 nm. The obtained i-layer amorphous silicon film was measured with a constant photocurrent measuring device (C
Then, the crystal defect density in the film was measured, and the crystal defect density was 4 × 10 ¹⁴ defects / cm ³ . Then, the silane gas (SiH
₄ ), hydrogen gas (H ₂ ) and phosphine gas (PH ₃ ) for n-type impurity element doping were used to form an n-layer amorphous silicon film having a thickness of 35 nm.

Then, after forming a transparent electrode film, a silver (Ag) film having a thickness of 400 nm to be a metal electrode film was vacuum-deposited on the entire surface of the substrate. Through the above steps, the amorphous silicon solar cell having the laminated structure shown in FIG. 1 was formed. The relationship between the initial efficiency and the deterioration rate of the thus obtained amorphous silicon solar cell was obtained. Here, the deterioration rate is a value obtained by dividing the optical power conversion efficiency after 10 hours deterioration by 5 sun by the initial optical power conversion efficiency. Results are shown in FIG.

Comparative Example 1 For comparison, after forming a transparent conductive film and a p-layer on a glass substrate in the same manner as in Example 1, silane (SiH) was used as a reaction gas without using a heater for heating the substrate surface. ₄ ) 600 sccm and hydrogen (H ₂ ) 300
An i-layer amorphous silicon film was formed using a mixed gas of 0 sccm, that is, a reaction gas in which the dilution ratio of silane to the hydrogen carrier gas was 5 times. Since the fine powder is easily generated in the plasma without the substrate surface heating heater, the dilution ratio of silane and hydrogen was increased. Further, in order to make the film formation rates the same, the power applied to the ladder antenna type electrode was lowered, and an ultra high frequency current having a frequency of 60 MHz was applied at 0.06 W / cm ² . Other film forming conditions were the same as in Example 1. The obtained i-layer amorphous silicon film was subjected to a constant photocurrent measuring device (CPM) and the crystal defect density in the film was measured. As a result, the crystal defect density was 10 × 10.
^{It was 14} pieces / cm ³ .

Then, after forming a transparent electrode film in the same manner as in Example 1, silver (A) having a thickness of 400 nm to be a metal electrode film is formed.
g) A film was formed on the entire surface of the substrate by vacuum evaporation. Through the above steps, the amorphous silicon solar cell having the laminated structure shown in FIG. 1 was formed. For the amorphous silicon solar cell thus obtained, the relationship between the initial efficiency and the deterioration rate was obtained in the same manner as in Example 1. The results are also shown in FIG.

(Comparative Example 2) For comparison, Example 1 was used.
After forming a transparent conductive film and a p-layer on a glass substrate in the same manner as described above, only silane (SiH ₄ ) was used as a reaction gas at 80 sc.
cm, and an i-layer amorphous silicon film was formed by using a substrate surface heater. The other film forming conditions for the i-layer amorphous silicon film were the same as in Example 1. The obtained i-layer amorphous silicon film was subjected to a constant photocurrent measuring device (CPM) and the defect density in the film was measured. As a result, the defect density was 1 × 10 ¹⁴ defects / cm ³ . Further, a transparent electrode film and a metal electrode film were formed in the same manner as in Example 1 to form an amorphous silicon solar cell. The deterioration rate of this amorphous silicon solar cell after being deteriorated for 10 hours is 0.9.
It was 0. Table 1 collectively shows the film forming conditions and the crystal defect density of the i-layer amorphous silicon film of the above-described Examples and Comparative Examples, and the deterioration rate of the amorphous silicon solar cell after 10 hours of deterioration.

[0026]

[Table 1]

From the results shown in Table 1, when an i layer is formed by the method of the present invention to form an amorphous silicon solar cell, the crystal defect density in the i layer amorphous silicon film is 1
0 ¹⁴ pieces / cm ³ It is possible to set the first half, so 1
It is clear that the deterioration rate after 0-hour deterioration can be maintained at 0.85 or more, and the light deterioration can be significantly suppressed. Moreover, since the film can be formed at a high film forming speed, high productivity can be maintained.

[0028]

As described in detail above, according to the method for forming a silicon semiconductor of the present invention, a high quality amorphous silicon semiconductor film having a low crystal defect density can be obtained.
If this is used as an i layer to form a pin structure amorphous silicon solar cell, photodegradation can be significantly suppressed. In addition, since it is possible to manufacture an amorphous silicon solar cell with high productivity while maintaining a high film formation rate, it greatly contributes to cost reduction.

[Brief description of drawings]

FIG. 1 is a diagram showing a cross-sectional structure of a unit cell of an amorphous silicon solar cell.

FIG. 2 is a schematic cross-sectional view showing the configuration of a plasma CVD apparatus used in the present invention.

FIG. 3 is a schematic view of a substrate surface heating heater used in the plasma CVD apparatus shown in FIG.

FIG. 4 is a schematic view of a ladder antenna type electrode used in the plasma CVD apparatus shown in FIG.

FIG. 5 is a diagram showing a relationship between an initial efficiency and a deterioration rate after 10 hours of deterioration of an amorphous silicon solar cell configured by using the present invention.

[Explanation of symbols]

1 ... Glass substrate, 2 ... Transparent electrode film, 3 ... p
Layer amorphous silicon film, 4 i layer amorphous silicon film, 5 n layer amorphous silicon film, 6
・ ・ ・ ・ Semiconductor film, 7 ・ ・ ・ ・ Metal electrode film, 10 ・ ・ ・ ・ ・ ・ Unit cell, 11 ・ ・ ・ ・ ・ ・ Reaction vessel, 12 ・ ・ ・ ・ Heating heater,
13: Heater main body, 14: Substrate, 15:
.... Substrate surface heating heater, 16 ... Wire heater
19 ... ・ Power source for heating the substrate surface, 20 ... Gas mixing box, 21 ... Gas introduction tube, 22 ... Reaction gas, 23
.... Ladder antenna type electrode, 24 ... Frame material, 25 ...
.... Ladder member, 29 ... High-frequency power source, 30 ... Impedance matching device

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuyoshi Tsujida             3-5-1, 717-1, Fukahori-cho, Nagasaki-shi, Nagasaki             Hishi Heavy Industries Ltd. Nagasaki Research Center F-term (reference) 4K030 AA06 AA10 AA17 BA29 BA30                       CA06 FA03 FA10 HA01 JA06                       JA10 JA18 LA16                 5F045 AA08 AB04 AC01 AD04 AD05                       AD06 AD07 AE19 BB09 BB12                       BB16 CA13 DA67 DP03 EB02                       EE12 EF05 EH04 EH19 EK07                       EK22 GB05                 5F051 AA05 CA16 CA36 CA37

Claims (7)

[Claims] 1. A method of forming an amorphous silicon thin film on a substrate by a plasma CVD vapor deposition method, comprising:
A substrate surface heating heater is arranged between the substrate arranged in the reaction vessel and a ladder antenna type electrode for generating glow discharge plasma, while flowing a reaction gas consisting of silane gas diluted in hydrogen gas into the reaction chamber, A method for forming a silicon semiconductor, wherein the substrate surface heating heater is used to control the surface temperature of the substrate, and the substrate surface heating heater is used to heat the reaction gas to form a film. 2. The method for forming a silicon semiconductor according to claim 1, wherein a mixing ratio of hydrogen gas and silane gas of the reaction gas is 1 to 1-10. 3. The mixing ratio of hydrogen gas and silane gas of the reaction gas is 1: 2 to 7.
A method of forming a silicon semiconductor according to claim 1. 4. The mixing ratio of hydrogen gas and silane gas of the reaction gas is 1: 3-5.
A method of forming a silicon semiconductor according to claim 1. 5. The surface temperature of the substrate is 140.degree.
The method for forming a silicon semiconductor according to claim 1, wherein the temperature is controlled to be ° C. 6. The temperature of the substrate surface heating heater is set to 75.
The method for forming a silicon semiconductor according to claim 1, wherein the temperature is controlled to be in the range of ℃ to 400 ℃. 7. The method for forming a silicon semiconductor according to claim 1, wherein the frequency of the high frequency power source current applied to the ladder antenna type electrode is 30 to 100 MHz.