JPH07211648A - Deposition of multilayer silicon film - Google Patents

Abstract

PURPOSE:To deposit an excellent multilayer silicon film having a wide optical band gap quite efficiently while suppressing the defect significantly. CONSTITUTION:A plasma gas containing hydrogen excited through electron cyclotron resonance and a compound of a chlorinated silane described the expresion SiHXCl4-X, (X is an integer of 0 to 3), are brought into continuous contact with the surface of a heated basic material, and then silicon is deposited by varying at least one condition of the surface temperature of the basic material, the intensity of electromagnetic wave causing the electron cyclotron resonance, and the distance between a plasma region and the surface of the basic material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel method for producing a multi-layered silicon film, which is useful as a photovoltaic device, as represented by a photovoltaic system.

[0002]

2. Description of the Related Art Amorphous silicon has excellent electrical characteristics such as high photoconductivity and low dark conductivity as compared with other photoelectric materials, and has high durability and no pollution. Therefore, it is used as a material forming a photovoltaic element represented by a solar power generation system.

As a general method for producing such amorphous silicon, chemical vapor deposition (hereinafter referred to as CVD), specifically, high frequency plasma CV is used.
D method, photo CVD method, electron cyclotron resonance (ECR)
A CVD method, a thermal CVD method, etc. are known.

Of these methods, the high frequency plasma CVD method is generally used. In this method, monosilane (SiH ₄ ) or disilane (Si ₂ H ₆ ) is used as a source gas, and in some cases, the source gas is hydrogen, He, or Ar.
Etc. and introduce it between the electrodes of a vacuum container equipped with a pair of electrodes inside, and apply high frequency power to form high frequency plasma, decompose the source gas and install it on the electrodes. An amorphous silicon film is formed on the formed base material. By this manufacturing method, the amorphous silicon film is deposited on the substrate at a rate of 60 to 1000 nm / min. Further, the photoelectric characteristics represented by the ratio of dark conductivity and photoconductivity (hereinafter referred to as photosensitivity) of the amorphous silicon film obtained by such a method become very excellent.

Further, the band gap (optical bandgap) of the amorphous silicon thus obtained is under film forming conditions such that the defect density in the film is minimized when the substrate temperature is around 250 ° C. When the film is deposited, 1.7 to 1.75
It is in the range of eV.

When the above amorphous silicon film is used as a photovoltaic element represented by a solar power generation system, in order to efficiently absorb solar energy,
A means for laminating silicon films having different band gaps is generally used.

For example, regarding a technique for producing an amorphous silicon multilayer film capable of efficiently absorbing solar energy by controlling the band gap, the following 4
A variety of methods have been favored. In the following, only the method for forming the two-layer film is shown as an example of the typical manufacturing method.

(1) SiH ₄ which is the main raw material gas, hydrogen which is a diluent gas, and a trace amount of additional elements are contained in the first container of two different evacuated containers which are separated by the gate valve and communicated with each other. A gaseous compound containing GeH ₄ or Sn is introduced, and high-frequency plasma C is introduced in the container.
A first layer silicon film is formed on the surface of the base material by the VD method. After that, the plasma is stopped once, the inside of the first vacuum container is evacuated to high vacuum, the gate valve of the communication part is opened, and
After moving the base material into the second container evacuated to high vacuum and closing the gate valve, only SiH ₄ which is the main raw material gas was introduced into the vacuum container, and like the formation of the first layer, A method of depositing a silicon film of a second layer on the first layer by a high frequency plasma CVD method.

According to the above-mentioned technique, an optical band gap of 1.0 to 1.7 eV in which a heterogeneous element such as Ge or Sn is added to a diamond structure having silicon as a base material.
A multilayer laminated film excellent in long-wavelength sensitivity is manufactured, which comprises a first layer and a second layer having an optical bandgap of 1.7 to 1.75 eV, which is composed of only silicon.

The control of the optical band gap by the addition of Ge and Sn as described above is performed by, for example, Optoelectronics 143.
Pp.-153 (1989).

(2) Using the same apparatus as in (1), SiH ₄ which is the main raw material gas is introduced into the first container, and a high-frequency plasma CVD method is used to form a silicon film of the first layer on the substrate. Perform precipitation. Then, in the same manner as in (1), the second base material is used.
Of the main raw material gas S into the container
iH ₄ and hydrogen as a diluting gas and any one kind of gas such as O ₂ , N ₂ , NH ₃ , CH ₄ and C ₂ H ₄ which is a trace additive element are introduced, and silicon and a trace amount are added by a high frequency plasma CVD method. A method of depositing a second layer which is a silicon film containing an additive element, that is, any one of O, N and C.

According to the above method, the optical band gap composed of only silicon has an optical band gap of 1.7 to 1.75 eV.
Of the first layer of No. 1 and the diamond structure having silicon as a base, and an optical band gap of 1.80 to 3.
A multilayer laminated film having a second layer of about 5 eV and excellent in short wavelength sensitivity is produced.

The control of the optical bandgap by adding O, N and C is performed by optoelectronics (O
ptoelectronics) pp.143-153 (1989).

(3) Using a device similar to (1),
SiH which is the main source gas in the container _FourIntroduce a high frequency
The first layer of silicon film is formed on the substrate by the plasma CVD method.
Perform precipitation. Then, in the same manner as in (1), the second
Move into the container and supply only hydrogen gas into the container
The surface of the silicon film formed in the first container with hydrogen gas.
Treat with plasma. After that, add the base material to the first container again.
Move it, silicon thin film (about 20 Å)
Gas) and hydrogen gas plasma moving to the second container
Repeat the process to obtain the second layer silicon film with the desired thickness.
How to form.

According to the above method, in the diamond structure having only silicon as a matrix, the first layer having an optical bandgap of 1.7 to 1.75 eV and the second layer having an optical bandgap of about 1.80 to 2.0 eV. A multilayer film composed of layers and having excellent short wavelength sensitivity is produced.

(4) Introducing SiH ₄ which is the main raw material gas into a vacuum vessel having a pair of electrodes inside and applying a high frequency voltage to the electrodes to form a high frequency gas plasma, thereby forming a raw material gas. By decomposing, the first-layer silicon film is deposited on the heating base material placed on the electrode. After that, the plasma is stopped once, the inside of the container is evacuated to a high vacuum, and then SiH ₄ which is the main raw material gas and hydrogen which is a diluting gas are introduced into the same container to re-form the high frequency gas plasma, and the high hydrogen dilution conditions Below, a method of depositing a second layer on a heated first layer.

According to the above method, in the diamond structure having only silicon as a matrix, the first layer having an optical bandgap of 1.7 to 1.75 eV and the second layer having an optical bandgap of about 1.80 to 2.0 eV. A multilayer film composed of layers and having excellent short wavelength sensitivity is produced.

[0018]

However, the formation of the amorphous silicon multilayer film by the conventional technique described above has the following manufacturing problems, and there is still room for improvement.

That is, in the above methods (1) and (2), the number of vacuum containers used for depositing a silicon film on a substrate is required only for the type of film to be formed, and a large equipment cost is required. Is required. Further, in forming each film, it is necessary to stop plasma once and move between different vacuum containers via a gate valve, which complicates the manufacturing operation. Further, as a result of the switching, defects may occur at the interface of the formed silicon multilayer film. Further, since the source gas is diluted with hydrogen to a high concentration, the deposition rate is remarkably reduced, and it takes a lot of time to include the time required for high vacuum exhaust before film deposition and the substrate moving time. There is a problem of cost.

Further, when the method (3) is used to form a multilayer silicon film, a vacuum container for depositing silicon and a vacuum container for plasma treatment are required, and the above (1) and Similar to the method (2), the equipment cost increases and there is a manufacturing problem. In addition, this method requires that film deposition and plasma treatment be performed alternately when depositing the second layer. Moreover, there is a problem that the hydrogen plasma treatment time is twice or more as long as the film deposition time, and the effective film formation time becomes long.

Further, when the multi-layered silicon film is deposited by the method (4), since the different elements are not added and the film formation is continuous, the problems in the method described above can be avoided. However, when forming the second layer after forming the first layer, it is necessary to stop the plasma and change the flow rates of the main raw material and the dilution gas. Further, since the source gas is diluted with hydrogen at a high concentration, there is a problem that the deposition rate of amorphous silicon is significantly reduced.

Therefore, in manufacturing a silicon multi-layered film for forming a silicon multi-layered film having photosensitivity over a wide wavelength range, the process and apparatus for producing the multi-layered silicon film are simplified and the formed multi-layered film is formed. It has been desired to suppress the formation of defects in the silicon film and to substantially reduce the manufacturing time by improving the film formation rate.

[0023]

[Means for Solving the Problems] The inventors of the present invention have conducted extensive studies to achieve the above object.

As a result, by using a specific silane compound as a raw material gas and bringing the raw material gas and a hydrogen-containing gas excited by electron cyclotron resonance into contact with each other under specific conditions, an amorphous silicon film is formed. It can be manufactured at a high growth rate, and by changing one or two or more of three independent conditions at the same time during the formation of such a silicon film, an optical band can be generated without generating a defect at a multilayer film interface. It has been found that the gap can be easily changed in a wide range, and as a result, an amorphous silicon multilayer film having photosensitivity over a wide wavelength range can be formed, and the present invention has been completed.

That is, the present invention is a chlorinated silane compound represented by the formula SiH _x Cl ₄ -x (where X is an integer of 0 to 3) and a hydrogen-containing gas plasmatized by being excited by electron cyclotron resonance. While continuously making contact with the heated substrate surface, at least one condition of the substrate surface temperature, the intensity of the electromagnetic wave that causes electron cyclotron resonance, and the distance between the plasma region and the substrate surface is changed. Is a method for producing a multi-layered silicon film, characterized in that silicon is deposited by means of the above method.

The formation of the multi-layered silicon film by the method of the present invention is carried out by depositing the silicon film in the same vacuum chamber in the same vacuum container when the silicon film is deposited in the second or more layers after the deposition of the first layer is completed. Since it can be performed without stopping, it is possible to significantly reduce equipment costs. Moreover, the film deposition process can be simplified by this,
It is possible to extremely efficiently manufacture an amorphous multilayer silicon film.

Further, an amorphous multi-layered silicon film having different optical band gaps between layers can be deposited at a high speed while suppressing the formation of defects at the stacking interface at a low rate, and at the same time, at a gas flow rate, Since there is no particular need to change gas phase conditions such as pressure, there is an advantage that a multi-layered silicon film having a film thickness can be deposited extremely efficiently.

The method of the present invention will be described in detail below.

In the present invention, the gas that is turned into plasma by electron cyclotron resonance (hereinafter referred to as plasma-producing gas) is not particularly limited as long as it is a gas containing at least hydrogen, but hydrogen is not particularly limited. capacity%
As described above, those containing 60 to 90% by volume are preferable.

In addition to hydrogen, it is also possible to make the plasma-producing gas contain an inert gas in the production of the silicon film. Examples of the inert gas include argon, helium, xenon, neon and the like.

Further, it is also possible to supply the above-mentioned raw material gas mixed with the plasma generating gas in the above-mentioned gas within a range that does not significantly impair the present invention, generally within a range of 50% by volume or less.

In the present invention, the method of exciting the plasma generating gas by electron cyclotron resonance is not limited, and a known method is adopted without particular limitation.

That is, all the methods that utilize the phenomenon of causing the cyclotron motion by causing the resonance absorption of the electromagnetic wave due to the interaction between the magnetic field and the electromagnetic wave can be implemented. For example,
A general method is to apply an electromagnetic wave and a magnetic field to the plasma generating gas at the same time.

As the above-mentioned electromagnetic waves, electromagnetic waves such as microwaves and very high frequency waves (VHF) are generally used. In particular, when microwaves are used, it is possible to stably form plasma. The power supplied by the electromagnetic waves is generally 2
It is 0 W to 2 kW, and preferably 100 to 600 W.

For the magnetic field, it is preferable to use an electromagnet whose strength can be adjusted by the applied power. Also,
The type of magnetic field is not particularly limited, such as a divergent magnetic field and a mirror magnetic field, but it is preferable to control the magnetic field so that the magnetic field is formed in the deposition space of the silicon film with an intensity of 875 Gauss or more.

In the present invention, the raw material gas is represented by the formula S
The use of a chlorinated silane compound represented by iH _X Cl _4-X (where X is an integer of 0 to 3) is an optical property of a silicon multilayer film obtained while maintaining a high film deposition rate. It is extremely important to control the dynamic band gap.

That is, as described above, a method of using a non-chlorinated compound such as monosilane as a raw material gas in the electron cyclotron resonance CVD method is known, but such a non-chlorinated silicon raw material such as monosilane is used. However, even if the specific conditions described above are changed, it becomes difficult for the obtained silicon film to efficiently control the optical band gap which is the object of the present invention.

Specific examples of the above chlorinated silanes include tetrachlorosilane, trichlorosilane, dichlorosilane and the like. These compounds exist in a gaseous state under the conditions for forming a silicon film.

The above-mentioned chlorinated silane compound is generally present alone, but may be supplied after being diluted with hydrogen or an inert gas within a range that does not significantly impair the effects of the present invention.

In the present invention, the mixing ratio of the plasma-converted hydrogen-containing gas and the raw material gas of the chlorinated silane compound is such that the atomic ratio of hydrogen in the hydrogen-containing gas and chlorine in the chlorinated silane compound (H / Cl) is preferably set to 0.1 to 50, and more preferably 5 to 10.

That is, when the atomic ratio is less than 0.1, the silicon film deposited on the substrate tends to be powdery, and the photoelectric conversion characteristics tend to deteriorate. Also, when the atomic ratio is larger than 50, similarly, the photoelectric conversion characteristics of the obtained silicon film are deteriorated, and the photoelectric conversion characteristics tend to be deteriorated.

The mixing ratio of the plasma-converted hydrogen-containing gas and the raw material gas made of a chlorinated silane compound preferably satisfies the above range. In particular, the flow rate ratio of the hydrogen-containing gas and the raw material gas is It is desirable to set the dilution rate of the hydrogen gas or the chlorinated silane compound so as to be in the range of 5 to 10.

In the present invention, the silicon film is deposited by bringing the mixed gas into contact with the surface of the base material. Such a base material is not particularly set, and is appropriately selected from known materials according to the process and application during element formation. For example, when the formed silicon thin film is used as a photoelectric conversion layer in a photoelectric conversion element, the base material includes quartz glass, soda lime glass, single crystal silicon,
Polycrystalline silicon, metals, ceramics, heat resistant polymers, transparent conductors, etc. can be used.

In the present invention, an important requirement is that the hydrogen-containing gas turned into plasma and the chlorinated silane compound are continuously brought into contact with each other on the surface of the heated substrate, the temperature of the substrate surface, electron cyclotron resonance. Intensity of electromagnetic waves that cause
By depositing silicon by changing at least one condition of the distance between the plasma region and the surface of the substrate, silicon films having different optical band gaps are deposited successively to form a multilayer silicon film.

In the present invention, the substrate surface temperature, which is one condition for depositing silicon, is preferably changed within the range of 100 ° C to 500 ° C. When the base material temperature is lower than the above temperature, a polymer film is formed, which causes a problem that photoelectric characteristics are deteriorated. On the contrary, when the base material temperature is higher than the above range, a large number of defects are formed in the film and the temperature is low. As before, the photoelectric properties of the film are degraded.

When the substrate temperature is changed within such a range, the optical bandgap of the obtained film decreases as the temperature rises, and the optical bandgap increases as the temperature drops.

The temperature of the surface of the base material can be adjusted by any known means without particular limitation. Generally, a method carried out by a heater mounted on a substrate support, a method carried out by an infrared lamp, and a method carried out by high frequency induction heating are suitably adopted. Among them, the method of adjusting the temperature with an infrared lamp is particularly preferable because the temperature can be switched quickly.

In the present invention, the intensity of the electromagnetic wave that causes electron cyclotron resonance, which is one condition for depositing silicon, is preferably adjusted in the range of 50 to 500W.

In the electromagnetic wave intensity range, increasing the electromagnetic wave intensity increases the optical bandgap, and conversely decreasing the electromagnetic wave intensity decreases the optical bandgap.

Furthermore, in the present invention, the distance between the plasma region and the substrate surface, which is one condition for silicon deposition, is
Although there are some differences depending on the size of the device used,
Generally, it is preferable to adjust in the range of 15 to 35 cm. That is, when the distance is less than 15 cm, the plasma tends to impact the film surface,
When it is larger than the above range, the deposition rate of the film is lowered and the effect of the present invention is not sufficiently exhibited.

The thickness of each layer of the silicon film formed by the present invention is not particularly limited, but is preferably 0.03 to 1 μm. In addition, the order of formation such as formation from the short wavelength side or the long wavelength side of the optical bandgap of each layer may be determined by appropriately selecting a desirable order in terms of the process or the characteristics of the object. .

The number of layers of the silicon film to be formed is generally suitable to be 2 to 4.

In the present invention, as long as the above-mentioned conditions are satisfied for forming the silicon film, known methods can be used for the other conditions without particular limitation.

For example, the pressure at the time of forming the silicon film is generally set in the range of 0.1 to 10 mTorr, and in particular,
0.5-5 mTorr is preferable.

As described above, in order to change the optical bandgap so as to achieve the above object of the present invention, the substrate temperature, the intensity of the electromagnetic wave which causes electron cyclotron resonance,
It is important to change at least one condition of the distance between the plasma region and the substrate surface, and it is desirable that the other conditions are not substantially changed.

Among the above-mentioned three conditions, the effect of the present invention is most prominent in the two factors of the intensity of the electromagnetic wave causing the electron cyclotron motion and the distance between the plasma region and the substrate surface.

The device for carrying out the present invention is not particularly limited. A typical device is, for example, a device as shown in the schematic view of FIG.

That is, it is composed of a plasma generation chamber 2 and a film formation chamber 1, and the microwave generation device 4 and the electromagnet 5 are arranged in the plasma generation chamber 2 so that they act on each other.
The plasma generation gas supply port 6 is connected to a position where both are affected. In addition, a support base 9 having a heater 10 built therein is provided in the film forming chamber, and the base material 3 is set thereon.

The plasma generating chamber 2 and the film forming chamber 1 communicate with each other, and the source gas is supplied to a position where the source gas can be supplied between the communication part of the film forming chamber 1 and the support base 9. Mouth 7
Are connected.

Further, the inside of the apparatus is controlled by the vacuum pump 11.
Adjusted to constant pressure. Reference numeral 12 is a valve for adjusting pressure, and reference numeral 8 is a flow rate adjuster for adjusting each gas flow rate.

In addition, the above apparatus includes an infrared heating lamp (not shown) for adjusting the surface temperature of the base material, and a microwave generator 4 as a controller for adjusting the intensity of electromagnetic waves that cause electron cyclotron resonance. A support platform elevating device 13 for adjusting the distance between the plasma region and the substrate surface is provided.

In the above apparatus, the plasma generation gas is supplied from the plasma generation gas supply port 6 to the plasma generation chamber 2 after its flow rate is controlled by the flow rate controller 8, and the microwave generated from the microwave generation device 4 is supplied there. And the magnetic field of the electromagnet 5 excites by electron cyclotron resonance and turns into plasma. The plasmatized gas is
It is supplied to the film forming chamber 1 from the communication part, and is mixed with the raw material gas whose flow rate is controlled by the flow rate regulator 8 from the raw material gas supply port 7 and then contacted with the base material 3 heated to a constant temperature by the heater 10. By doing so, a silicon film is formed on the surface of the base material.

[0063]

As will be understood from the above description, the method of the present invention is a combination of the electron cyclotron resonance CVD method and the use of a chlorinated silane compound as a silicon raw material.
This is based on the knowledge that the optical band gap of the silicon film to be formed can be controlled only by changing specific conditions, and that each silicon film can be formed at an extremely high deposition rate.

With this structure, since the multilayer silicon film can be formed in the same vacuum container, not only the throughput is greatly improved, but also the manufacturing equipment and the manufacturing process are simplified. It

Further, since it is not necessary to stop the plasma, it is possible to form a multilayer silicon film in which the generation of defects between layers is significantly suppressed. Furthermore, since adjusting the optical band gap of the multilayer silicon film does not require a high degree of dilution of the source gas with hydrogen, the high deposition rate can be sufficiently maintained.

Therefore, according to the method of the present invention, it is possible to extremely efficiently produce an excellent multi-layered silicon film having a wide optical band gap and very few defects, and its industrial value is extremely high. It is a thing.

[0067]

EXAMPLES In order to describe the present invention more specifically, examples will be shown, but the present invention is not limited to these examples.

In the examples and comparative examples, the photoconductivity, the wavelength dependence of the photoconductivity, and the defect density in the film of the obtained silicon multilayer films were measured by the following methods.

(1) Photoconductivity An aluminum electrode having an electrode interval of 0.2 mm and an electrode length of 38 mm was formed by vacuum evaporation on a silicon multilayer film formed on a quartz substrate, and a DC voltage of 100 V was applied between the electrodes. Conductivity was measured by applying.

The conductivity obtained by irradiating with light of 100 mW / cm ² was defined as the photoconductivity.

(2) Photoconductivity Wavelength Dependence The light controlled by a monochromator is 400 nm.
The sample was irradiated with light from 1 to 700 nm to examine the wavelength dependence of photoconductivity. At this time, the maximum value of the obtained photoconductivity was set to 1 and standardized.

(3) Defect density in film Amorphous silicon and related materials (AMORPHOUSSILICON AND RERATED METERIALS)
It was measured by the constant photocurrent measuring method described on pages 297 to 327 (1988) and shown as the defect density in the film.

Example 1 Using the apparatus shown in FIG. 1, a silicon multilayer film was formed under the following conditions.

First, 20 SCCM of high-purity hydrogen as a plasma generation gas was supplied to the plasma generation chamber 2 to form ECR plasma. At this time, the microwave input power is 10
The magnetic field was set to 0 W and the magnetic field was set to 875 Gauss. In this state, dichlorosilane as a raw material gas was supplied to the film forming chamber 1 in an amount of 2.5 SCCM, and the gas plasma was brought into contact with the substrate 3 made of quartz glass heated to 230 ° C. by the heater 10. , A silicon thin film was deposited.

The reaction pressure was set to 3 mTorr by the vacuum pump 11, and the distance between the substrate surface and the plasma region (contact point between the film forming chamber and the plasma generating chamber) was set to 17 cm.
After forming the film for 5 minutes, the plasma was not stopped, only the microwave power was increased to 300 W, and the film was formed for another 3 minutes to obtain a silicon multilayer film of about 0.6 μm.

The film thickness of the multilayer silicon film on the quartz substrate was measured by the stylus method, and then an aluminum electrode was formed on the substrate, and electrical measurement was performed.

Independently of this experiment, the films were formed under the above-mentioned conditions for forming the respective silicon films, and as a result, the optical band gap of the film obtained at a microwave power of 100 W was 1.7 eV. Defect density is 7 × 10 ¹⁵ cm
^-3 , the optical band gap of the film formed with microwave power of 300 W is 1.85 eV, and the defect density is 2 × 1.
It was 0 ¹⁵ cm ^-3 .

100 mW / c of the obtained multilayer silicon film
Table 1 shows the measurement results of the photoconductivity and the wavelength dependence of the photoconductivity when irradiated with white light having an intensity of m ² . For comparison, Table 2 shows the wavelength dependence of photoconductivity of each monolayer film.

Example 2 After forming a film for 5 minutes under the same conditions as in Example 1 except that the microwave power was fixed at 300 W and only the substrate position was changed from 17 cm to 32 cm, The plasma was not stopped, the substrate position was returned to 17 cm, and the film formation was further performed for 3 minutes to obtain a silicon multilayer film of about 0.6 μm.

As in Example 1, the silicon film was formed under the respective film forming conditions.
When a silicon film is formed at 2 cm, the resulting film has an optical band gap of 1.70 eV and a defect density of 8 ×.
When the film was formed at 10 ¹⁵ cm ^-3 and the substrate position was 17 cm, the optical band gap was 1.85 eV and the defect density was 3 × 10 ¹⁵ cm ^-3 .

Further, 100 m of the obtained silicon multilayer film
Similar to Example 1, Table 1 shows the photoconductivity and the wavelength dependence of the photoconductivity when irradiated with white light having an intensity of W / cm ² .

Example 3 Under the same conditions as in Example 1 except that only the substrate temperature was set to 150 ° C., a silicon film was formed on the surface of the substrate for 3 minutes, and then infrared heating was performed without stopping plasma. The strength of the lamp was increased to raise the substrate temperature to 300 ° C., and a silicon film was formed for 5 minutes to obtain a multilayer silicon film having a thickness of 0.6 μm. The temperature of the surface of the base material was measured by a thermocouple in point contact with the base material.

Evaluation of the obtained multilayer silicon film was carried out in Example 1.
The same method was used.

As in Example 1, the silicon film was formed under the respective film forming conditions.
When the silicon film is formed at 50 ° C., the resulting film has an optical band gap of 1.85 eV and a defect density of 2 ×
The film thickness was 10 ¹⁵ cm ⁻³ , the optical band gap was 1.7 eV, and the defect density was 8 × 10 ¹⁵ cm ⁻³ when the film was formed at a substrate temperature of 300 ° C.

Further, 100 m of the obtained silicon multilayer film
Similar to Example 1, Table 1 shows the photoconductivity and the wavelength dependence of the photoconductivity when irradiated with white light having an intensity of W / cm ² .

[0086]

[Table 1]

[0087]

[Table 2]

[Brief description of drawings]

FIG. 1 is a schematic view showing a typical embodiment of a manufacturing apparatus used in the method of the present invention.

[Explanation of symbols]

 1 Film-forming chamber 2 Plasma generation chamber 3 Base material 4 Microwave generator 5 Electromagnet 6 Plasma generation gas supply port 7 Raw material gas supply port 8 Flow controller 9 Support stand 10 Heater 11 Vacuum pump 12 Valve 13 Support stand lifting device

Claims (1)

[Claims] 1. A hydrogen-containing gas excited by electron cyclotron resonance and plasmatized, and a formula SiH _x Cl _4-x.
(Where X is an integer of 0 to 3), while continuously contacting the chlorinated silane compound on the heated substrate surface, the substrate surface temperature and the intensity of the electromagnetic wave that causes electron cyclotron resonance. A method for producing a multi-layered silicon film, which comprises depositing silicon by changing at least one condition of a distance between a plasma region and a substrate surface.