JP2000228369A - Apparatus and method for silicon film forming - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a silicon film forming apparatus capable of forming a silicon film having uniform film quality. SOLUTION: This silicon film forming apparatus 20 is one in which a substrate 8 coated with a semiconductor raw material liquid is heated by a heater 6 to form a silicon film on the substrate 8 and is arranged at a position confronting a coated face 8a of the semiconductor raw material liquid of the substrate 8, and comprises a silicon-adhering member 9, having a raw material adhering face 9a for adhering an evaporated semiconductor raw material from the coated face 8a due to heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicon film forming apparatus and a silicon film forming method, and more particularly, to a silicon film forming apparatus and a silicon film for a photoelectric conversion device such as an LSI, a thin film transistor, a solar cell, and a photoconductor. The present invention relates to a film forming method.

[0002]

2. Description of the Related Art Conventionally, a polycrystalline silicon film (hereinafter referred to as "po
As a method for forming an amorphous silicon film (hereinafter, referred to as an “a-Si film”) or an amorphous silicon film (hereinafter, referred to as an “a-Si film”), a thermal CVD (Chemical Vapor Dep.
osition) method, a plasma CVD method, an optical CVD method, and the like.
The VD method and the plasma CVD method are widely used for forming the a-Si film.

As a CVD method using a higher-order silane gas, a method of thermally decomposing a higher-order silane gas under a pressure higher than the atmospheric pressure (Japanese Patent Publication No. 4-62073) and a method of thermally decomposing a cyclic silane gas (Japanese Patent Publication No. Hei. 5-62073). No.-469), a method using a branched silane gas (Japanese Patent Application Laid-Open No. 60-26665), and a method using a higher-order silane gas of trisilane or higher.
Method of performing thermal CVD at 0 ° C. or lower (Japanese Patent Publication No. 5-56852)
And the like have been proposed. However, these CVD
A film that can be formed by the CVD method is an a-Si film, and these CVD methods have the following problems.

That is, since a gas phase reaction is used, particles are generated in the gas phase, which causes problems such as contamination of the silicon film forming apparatus and reduction in the yield of the device. Since the raw material is used in a gaseous state, it is difficult to obtain a film having good step coverage on a substrate having an uneven surface. The silicon film formation speed is low and the throughput is low. In the plasma CVD method, a complicated and expensive device such as a high frequency generator is required.
For example, an expensive high vacuum device is required.

In order to avoid these problems, a method has been proposed in which a liquid material is used instead of a gas phase reaction. For example, a method of forming a silicon film on a substrate by applying a liquid higher silane to a substrate and then raising the temperature, through a thermal history including a temperature raising process, and causing a decomposition reaction in the coating film (Japanese Patent Laid-Open No. No. 7-267621) or a general formula-(SiR) n- (R is at least one selected from the group consisting of hydrogen, an alkyl group having 2 or more carbon atoms having a β-position hydrogen, a phenyl group, and a silyl group) A method in which a solution of polysilane represented by formula (1) is applied onto a substrate and then silicon is released by thermal decomposition (Japanese Patent Application Laid-Open No. 9-237927).
There is.

[0006]

A silicon film used for a photoelectric conversion device such as an LSI, a thin film transistor, a solar cell, and a photoconductor needs to have a uniform film quality formed on a substrate. However, in the method of applying a material having a high vapor pressure such as liquid higher silane and applying thermal decomposition, the applied semiconductor material liquid is thermally polymerized by heating to form a silicon film from the interface side between the semiconductor material liquid and the substrate. Then, a layer formed on the substrate (referred to as a “liquid phase growth layer”) and a portion of the semiconductor material diffused into the atmosphere by heating from the applied surface, and the evaporation from the applied surface stopped. Thereafter, since a multilayer structure is formed with a layer formed by thermal polymerization on the substrate (referred to as a “vapor phase growth layer”), uniform film quality cannot be obtained. This is the same not only when a raw material consisting of only a liquid raw material is used but also when a raw material solution obtained by dissolving the raw material in a solvent is used.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object a silicon film forming apparatus and a silicon film forming method capable of forming a silicon film having a uniform film quality while avoiding the above problems. To provide.

[0008]

According to the present invention, there is provided a silicon film forming apparatus for forming a silicon film on a substrate by heating a substrate coated with a semiconductor raw material liquid by a heating means. A silicon film forming apparatus provided with a silicon attachment member provided at a position opposed to an application surface and having a material attachment surface for attaching a semiconductor material vaporized from the application surface by heating.

Thus, in the silicon film forming apparatus of the present invention, a liquid semiconductor material having a high vapor pressure, such as liquid higher silane, or a solution of the semiconductor material is applied onto the substrate, and the silicon film is decomposed by heating. At the time of formation, the silicon particles and the semiconductor raw material that have been vaporized by heating from the application surface can be made to adhere to the raw material attachment surface of the silicon attachment member disposed at a position facing the semiconductor material liquid application surface of the substrate. As a result, it is possible to form a silicon film consisting only of a thermopolymerized film layer (liquid phase growth layer) formed by thermally polymerizing higher silane or the like of the applied semiconductor raw material liquid in the coating liquid on the substrate.
Therefore, it is possible to prevent the formation of a multi-layer structure of silicon composed of the vapor phase growth layer and the liquid phase growth layer on the substrate, and to obtain a silicon film having a uniform film quality.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A silicon film forming apparatus according to the present invention
A chamber accommodating at least the substrate, a substrate supporting means for supporting the substrate, a heating means for heating the substrate supported by the support portion, a raw material liquid supplying means for supplying a semiconductor raw material liquid to the substrate in the chamber, Pressure adjusting means for pressurizing and depressurizing the inside of the chamber with a gas, and a silicon attachment member disposed at a position facing the surface of the substrate to which the semiconductor material liquid is applied, for attaching the semiconductor material vaporized by heating.

The chamber is composed of two chambers, a coating chamber for applying a semiconductor raw material liquid to a substrate in the chamber and a film forming chamber for heating a substrate coated with the semiconductor raw material liquid to form a silicon film on the substrate. Are preferred. In this case, for example,
A gate valve separates the chamber into the above two chambers,
It is preferable to provide a substrate transporting unit that transports the substrate coated with the semiconductor raw material liquid in the coating chamber to the film forming chamber. Examples of the substrate transfer means include a robot mechanism having a manipulator, a conveyor, and the like. The coating chamber is preferably provided with a mechanism for uniformly spreading the semiconductor raw material liquid supplied to the substrate on the substrate, for example, a spin coater.

In the case where the application of the semiconductor raw material liquid and the heating of the substrate are performed in one chamber, the substrate transporting means becomes unnecessary, but the mechanism for developing the raw material liquid such as a spin coater, the heating means, and the appropriateness of the raw material liquid supplying means are appropriate. An arrangement is required. The substrate supporting means supports the substrate horizontally or at a predetermined angle such that the application surface of the substrate coated with the semiconductor raw material liquid faces the silicon adhering member. Alternatively, it is preferable that the substrate can be prevented from being displaced by being placed on a horizontal surface and inserted into the fixed frame.

When depositing the vaporized semiconductor raw material, it is essential that the temperature of the silicon adhering member is set to be lower than the temperature of the base material coating surface of the substrate. For this reason, it is preferable that the heating means be disposed such that the silicon attachment member is located on the distal side of the base. The heating means is preferably one capable of raising the temperature to a temperature at which the solid compound of the semiconductor raw material becomes liquid so that the semiconductor raw material liquid can be applied. Specific examples of the heating means include a ceramic heater,
And an infrared lamp.

Preferably, the silicon attachment member according to the present invention is disposed so as to cover the substrate at a predetermined distance from the surface of the substrate to which the semiconductor raw material liquid is applied, at least during heating. The silicon adhering member is a member for adhering a gas-phase product formed by thermally polymerizing a semiconductor raw material liquid vaporized from an application surface in an atmosphere, and preferably has an appropriate adhering surface for adhering the gas-phase product. Examples of the material of the silicon attachment member include quartz.

It is preferable that the raw material adhering surface of the silicon adhering member is formed of a plate-shaped or mesh-shaped member formed in a flat shape or a bowl shape. The main surface of the silicon adhering member is a portion facing the surface of the substrate to which the semiconductor material liquid is applied, but the surface or side surface on the opposite side can also be the adhering surface. It is desirable that the raw material adhering surface is disposed so as to face the surface of the substrate to which the semiconductor raw material liquid is applied at an interval of 5 to 180 mm. Further, it is preferable that the raw material adhering surface has an area sufficient to project at least a projected shadow of the substrate.

If the material-adhering surface is formed in a planar shape, the vaporized semiconductor raw material can be uniformly adhered. However, if it is formed in a bowl-like shape, diffusion in a direction parallel to the surface can be prevented.
Further, if a mesh-shaped member is used on the surface on which the raw material is adhered, it is possible to suppress an increase in pressure in the bowl that occurs when the material is formed in a bowl shape or the like. The shape of the mesh forming the mesh is not particularly limited, and examples thereof include a lattice (rectangle), a polygon, a circle, and an ellipse. The opening (size) of the mesh and the diameter and width of the wire constituting the mesh are not particularly limited.

The semiconductor raw material liquid in the present invention comprises only a liquid raw material or a solution of the raw material. The semiconductor raw material liquid has a general formula Si _n R _m Sy _i (n is an integer of n ≧ 1, R
Are each independently selected from the group consisting of hydrogen and organic groups. Sy is a silyl group, m + i = 2n + 2, m is an integer of m ≧ 0, i is an integer of i ≧ 0) or Si _q R _t Sy
_w (q is an integer of q ≧ 3, R is each independently selected from the group consisting of hydrogen and an organic group. Sy is a silyl group, t + w
= 2q, t is an integer of t ≧ 0, w is an integer of w ≧ 0), and Si _n X _k H _j (X is a halogen atom, k + j = 2n)
+2, k is an integer of k ≧ 1, j is an integer of j ≧ 0, and n is n ≧
A compound represented by the formula: Si _x X _y H _z (X is a halogen atom, y + z = 2q, y is an integer of y ≧ 1, z is an integer of z ≧ 0, and q is an integer of q ≧ 3) It is. In general formula described above Si _q R _t Sy _w and Si _q X _y H
The compound of _z represents a cyclic silane derivative.

Examples of the organic group include ethyl, t-butyl
Octadecyl, phenyl and the like. these
As a semiconductor raw material compound containing an organic group, SiH_Three(C₁₈
H₃₇) [Octadecylsilane], Si (C_TwoH_Five)_Four[Tetra
Ethylsilane], tetraphenylsilane [Si (C₆H
_Five)_Four)] 1,1,2,2,3,3,4,4,5,5
6,6-dodeca-tert-butylhexasilane [Si₆H
_Two(C (CH_Three)_Three)₁₂)], Octadecaethylocta
Silane [Si₈(C_TwoH_Five)₁₈], Octa t-butyl
Clotetrasilane [Si_Four(C (CH_Three)_Three)₈] Nor
Maltetrasilane (n-Si_FourH_Ten), Normal penta
Silane (n-Si_FiveH₁₂), Normal hexasilane (n
-Si₆H₁₄), Normal heptasilane (n-Si₇H
₁₆), Cyclopentasilane (Si_FiveH_Ten), Cyclohex
Sasilane (Si₆H₁₂), Cyclodecasilane (Si_TenH
₂₀) And the like. Examples of the halogen atom include
Nitrogen, chlorine, bromine and the like. These halogen sources
Tribromosilane
(SiHBr _Three), Hexachlorodisilane (Si_TwoCl
₆), Octafluorotrisilane (Si_ThreeF₈), Dode
Cachloropentasilane (Si_FiveCl₁₂) Etc.
You. These compounds may be used alone or as a mixture.
May be used.

Among the above compounds, normal tetrasilane (n-Si ₄ H ₁₀ ) and normal pentasilane (n-Si
₅ H _12), normal hexa silane _{(n-Si 6 H 14)} ,
Normal hepta silane _{(n-Si 7 H 16)} , cyclopentasilane (Si ₅ H _10), cyclohexasilane (Si ₆
H ₁₂ ), tribromosilane (SiHBr ₃ ), hexachlorodisilane (Si ₂ Cl ₆ ), octafluorotrisilane (Si ₃ F ₈ ), octadecylsilane (SiH
₃ (C ₁₈ H ₃₇ )), tetraethylsilane Si (C
_{Since 2} H ₅ ) _{4 and the} like and their isomers are liquid at ordinary temperature, each compound itself can be applied to a substrate, but may be dissolved in a solvent and used as a solution. Examples of the solvent include toluene, xylene, petroleum ether and the like.

Among the above compounds, normal decasilane (n-Si ₁₀ H ₂₂ ) and cyclodecasilane (Si
₁₀ H ₂₀ ), dodecachloropentasilane (Si ₅ C
l ₁₂ ), tetraphenylsilane (Si (C
_{6 H 5) 4), 1,1,2,2,3,3,4,4,5} ,
5,6,6-dodeca t-butylhexasilane (Si ₆ H
₂ (C (CH ₃ ) ₃ ) ₁₂ ), octadecaethyl octasilane (Si ₈ (C ₂ H ₅ ) ₁₈ ), octa-tert-butylcyclotetrasilane (Si ₄ (C (CH ₃ ) ₃ ) ₈ ) , And these isomers are solid at ordinary temperature, and thus each compound is dissolved in a solvent and used as a solution. Examples of the solvent include toluene, xylene, petroleum ether and the like.

By raising the ambient temperature to a temperature at which these compounds become liquid, the semiconductor raw material liquid can be applied to the substrate. The formation of the silicon film according to the present invention is preferably performed in an inert gas atmosphere. Examples of the inert gas include helium, neon, argon, xenon, and the like. The pressure of the inert gas in the inert gas atmosphere is preferably 10 kPa or more.

According to the present invention, in a method of forming a silicon film on a substrate by applying a semiconductor raw material liquid on a substrate and then heating the substrate, the semiconductor raw material liquid is applied to a thickness of 1 μm on the substrate. It is preferable to carry out the above. The coating thickness of the semiconductor raw material liquid on the substrate is adjusted and controlled by a raw material spreading mechanism on the substrate based on a rotation speed, a rotation time, and the like of the spin coater, and a raw material supply amount on the substrate. After applying the semiconductor raw material liquid according to the present invention on a substrate,
As a silicon film forming apparatus for forming a silicon film on the substrate by heating, for example, an apparatus as shown in FIG. 1 or FIG. 2 is mentioned, and the above object is achieved by the following steps.

In order to form a silicon film according to the present invention,
First, a substrate (substrate) is fixed in a chamber for film formation,
A semiconductor raw material liquid, that is, a liquid semiconductor raw material or a solution of the semiconductor raw material, is applied to the surface of the base to a thickness of preferably 1 μm or more. Next, the substrate and the application surface are heated by the heating means. At this time, in the coating liquid, a silicon film is formed and grown from the interface between the coating liquid, the semiconductor raw material liquid and the substrate by thermal polymerization, and is deposited on the substrate as a liquid phase growth layer. Conventionally, a part of the semiconductor raw material vaporized from the application surface and diffused into the atmosphere is attached to the liquid phase growth layer after the vaporization from the application surface stops, and is thermally polymerized by heating.

A part of the semiconductor raw material diffused in the atmosphere is thermally polymerized in the atmosphere (in the gas phase) by radiant heat from a heat source such as a substrate and a heater, and is superposed on the liquid phase growth layer. Thus, a silicon film having a multilayer structure in which a liquid phase growth layer and a vapor phase growth layer are stacked is formed, and it is difficult to form uniform film quality. In the present invention, a vapor-phase product deposited as a vapor-phase growth layer on the liquid-phase growth layer,
Since the liquid deposition layer is selectively deposited on the silicon deposition member disposed at a position opposed to the coating surface of the substrate, a uniform silicon film having only a liquid phase growth layer deposited thereon can be formed.

[0025]

The embodiments of the present invention will be specifically described below. <Example 1> The apparatus 20 shown in Fig. 1 was used as an experimental apparatus. The apparatus 20 has a coating chamber 1 and a film forming chamber 2 formed in a chamber, and both chambers are provided with a gate valve 11.
Are releasably isolated by In the coating chamber 1, a supply line 3 and an exhaust line 5 for a semiconductor raw material liquid are provided.
Is provided with a gas supply line 4 and an exhaust line 5. In addition, a spin coater 7 is provided in the coating chamber 1, and a plate-like silicon made of quartz is opposed to the heater 6 and the quartz substrate 8 placed on the heater 6 in the film forming chamber 2. An attachment member 9 is provided. Silicon adhesion member 9
On the surface of the substrate 8 opposite to the application surface 8a, a planar raw material attachment surface 9a is formed.

The heater 6 is a ceramic heater having a heating surface on the upper surface in the figure. Substrate support means for fixing the substrate 8 by inserting the placed quartz substrate 8 into a fixing frame are formed on the upper surface of the spin coater 7 in the drawing and the heating surface of the heater 6 (not shown). . Further, there is a substrate transfer means (not shown) for connecting the coating chamber 1 and the film forming chamber 2 to transfer the substrate 8 on the spin coater 7 onto the heater 6.

Using a liquid mixture of higher order silanes of normal tetrasilane, normal pentasilane, and normal hexasilane as a semiconductor raw material liquid, a film was formed in the following procedure. First, with the gate valve 11 opened, the coating chamber 1 and the film forming chamber 2 were evacuated to 2 × 10 ⁻⁴ Pa, and helium gas was introduced from the gas supply line 4 to 40 kPa. Next, 1.6 cm ³ of a liquid higher silane mixture of normal tetrasilane, normal pentasilane, and normal hexasilane is dropped onto the quartz substrate 8 from the semiconductor raw material supply line 3, and then the entire surface of the quartz substrate 8 is spin-coated. Was applied. Then, again, the gas supply line 4
Helium gas is introduced into the coating chamber 1 and the film forming chamber 2 from
Pressurized to 100 kPa. Next, the quartz substrate 8 was moved onto the heater 6 and the gate valve 11 was closed.

Thereafter, helium gas was exhausted from the exhaust line 5, and the pressure in the film forming chamber 2 was set to 40 kPa. The quartz substrate 8 was heated to 600 ° C. at 100 ° C./min, and the substrate temperature was maintained at 600 ° C. for 30 minutes to form a silicon film on the quartz substrate 8. During the temperature increase and the temperature holding, the helium gas was appropriately exhausted from the exhaust line 5 to maintain the pressure in the film forming chamber 2 at 40 kPa. After film formation, the silicon adhering member 9
Had silicon attached to it. When the cross-sectional structure of the silicon film obtained on the substrate 8 was observed with a transmission electron microscope, no multilayer structure was observed.

<Embodiment 2> The glass substrate 8 was heated at 100 ° C./min.
Then, a silicon film was formed in the same manner as in Example 1 except that the temperature was raised to 450 ° C. and the substrate temperature was maintained at 450 ° C. for 30 minutes. After the film formation, silicon was adhered to the silicon adhered member 9. When the cross-sectional structure of the silicon film obtained on the substrate 8 was observed with a transmission electron microscope, no multilayer structure was observed.

Example 3 Octa-t was used as a semiconductor raw material liquid.
-Butylcyclotetrasilane (Si_Four(C (C
H _Three)_Three)₈) Using a toluene solution of
After coating on the plate 8, the toluene is evaporated and
The temperature of the substrate 8 is raised to 450 ° C. at 100 ° C./min.
Same as Example 1 except that the substrate temperature was maintained at 30 ° C. for 30 minutes.
Thus, a silicon film was formed. After film formation,
Silicon was adhered to the adhesive member 9. On the substrate 8
Observe the cross-sectional structure of the obtained silicon film with a transmission electron microscope.
On observation, no multilayer structure was observed.

<Example 4> A petroleum ether solution of dodecachloropentasilane (Si ₅ Cl ₁₂ ) was used as a semiconductor raw material liquid, and was applied on a glass substrate 8, and then the petroleum ether was evaporated. 8 was heated to 450 ° C. at 100 ° C./min, and a silicon film was formed in the same manner as in Example 1 except that the substrate temperature was maintained at 450 ° C. for 30 minutes. After the film formation, silicon was adhered to the silicon adhered member 9. When the cross-sectional structure of the silicon film obtained on the substrate 8 was observed with a transmission electron microscope, no multilayer structure was observed.

Example 5 An apparatus 30 shown in FIG. 2 was used as an experimental apparatus. The coating chamber 1 of the apparatus 30 includes a semiconductor raw material supply line 3 and an exhaust line 5, and the film forming chamber 2 includes a gas supply line 4 and an exhaust line 5. Also,
A spin coater 7 is provided in the coating chamber 1, and a mesh-like silicon attachment member 10 is provided in the film forming chamber 2 so as to cover the heater 6 and the quartz substrate 8 placed on the heater 6. . The mesh-like silicon attachment member 10 includes:
The surface of the wire rod which is formed in a bowl shape using quartz as a material and constitutes the mesh is the raw material attachment surface 10a. A liquid higher order silane mixture of normal tetrasilane, normal pentasilane, and normal hexasilane was used as a semiconductor raw material liquid, and a film was formed in the following procedure.

First, with the gate valve 11 opened,
After evacuating the coating chamber 1 and the film forming chamber 2 to 2 × 10 ⁻⁴ Pa, helium gas is supplied from the gas supply line 4 to 40 kPa.
Introduced. Next, 1.6 cm ³ of a liquid higher silane mixture of normal tetrasilane, normal pentasilane, and normal hexasilane is dropped onto the quartz substrate 8 from the semiconductor raw material supply line 3, and then the entire surface of the quartz substrate 8 is spin-coated. Applied. Next, again, the gas supply line 4
Helium gas is introduced into the coating chamber 1 and the film forming chamber 2 from
The pressure was increased to 00 kPa. Next, the quartz substrate 8 was moved onto the heater 6 and the gate valve 11 was closed.

Thereafter, helium gas was exhausted from the exhaust line 5, and the pressure in the film forming chamber 2 was set to 40 kPa. The quartz substrate 8 was heated to 600 ° C. at 100 ° C./min, and the substrate temperature was maintained at 600 ° C. for 30 minutes to form a silicon film on the quartz substrate 8. During the temperature increase and the temperature holding, the helium gas is appropriately exhausted from the exhaust line 5 to reduce the pressure in the film forming chamber 2 to 40.
kPa. After the film formation, silicon was adhered to the silicon adhered member 9. When the cross-sectional structure of the silicon film obtained on the substrate 8 was observed with a transmission electron microscope, no multilayer structure was observed.

<Embodiment 6> The glass substrate 8 was heated at 100 ° C./min.
Then, a silicon film was formed in the same manner as in Example 3, except that the temperature was raised to 450 ° C. and the substrate temperature was maintained at 450 ° C. for 30 minutes. After the film formation, silicon was adhered to the silicon adhered member 9. When the cross-sectional structure of the silicon film obtained on the substrate 8 was observed with a transmission electron microscope, no multilayer structure was observed.

Comparative Example In order to compare the formation of a silicon film by the silicon film forming apparatus of the present invention with the formation of a silicon film by the conventional silicon film forming apparatus, a conventional silicon film forming apparatus 100 shown in FIG. Was used to form a silicon film. The apparatus 100 is different from the silicon film forming apparatuses 20 and 30 of the present invention in that the apparatus 100 does not include members corresponding to the silicon attachment members 9 and 10. A silicon film was formed by the following procedure using a liquid higher silane mixture of normal tetrasilane, normal pentasilane, and normal hexasilane as a semiconductor raw material liquid.

First, with the gate valve 11 opened,
After evacuating the coating chamber 1 and the film forming chamber 2 to 2 × 10 ⁻⁴ Pa, helium gas is supplied from the gas supply line 4 to 40 kPa.
Introduced. Next, 1.6 cm ³ of a liquid higher silane mixture of normal tetrasilane, normal pentasilane, and normal hexasilane is dropped onto the quartz substrate 8 from the semiconductor raw material supply line 3, and then the entire surface of the quartz substrate 8 is spin-coated. Applied. Next, again, the gas supply line 4
Helium gas is introduced into the coating chamber 1 and the film forming chamber 2 from
Pressurize to 100 kPa and heat the quartz substrate 8 with a heater 6
It was moved upward, and the gate valve 11 was closed. Thereafter, helium gas is exhausted from the exhaust line 5 to make the pressure in the film forming chamber 2 40 kPa, and the quartz substrate 8 is heated at 100 ° C./min.
The temperature was raised to 600 ° C., and the substrate temperature was maintained at 600 ° C. for 30 minutes to form a silicon film on the quartz substrate 8. Helium gas was appropriately exhausted from the exhaust line 5 during the temperature increase and the temperature maintenance to maintain the pressure in the film forming chamber 2 at 40 kPa. Quartz substrate 8
When the cross-sectional structure of the silicon film obtained above was observed with a transmission electron microscope, it was confirmed that the silicon film had a multilayer structure with different crystallinity.

[0038]

According to the present invention, a liquid semiconductor material having a high vapor pressure, such as liquid higher silane, or a solution of the semiconductor material is applied to a substrate and heated to decompose to form a silicon film. In addition, the silicon particles and the semiconductor raw material that are vaporized by heating from the application surface can be attached to the raw material attachment surface of the silicon attachment member disposed at a position of the base opposite to the semiconductor material liquid application surface. As a result, it is possible to form a silicon film consisting only of a thermopolymerized film layer (liquid phase growth layer) formed by thermally polymerizing higher silane or the like of the applied semiconductor raw material liquid in the coating liquid on the substrate. Therefore, it is possible to prevent the formation of a multi-layer structure of silicon composed of the vapor phase growth layer and the liquid phase growth layer on the substrate, and to obtain a silicon film having a uniform film quality. In addition, it is possible to avoid problems such as cost in the conventional silicon film formation such as the CVD method, and the uniformity of the formed film quality in the film widens the application of the silicon film to device processes and the like.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of an apparatus used for forming a silicon film according to Examples 1, 2, 3, and 4 of the present invention.

FIG. 2 is a schematic cross-sectional view of an apparatus used for forming a silicon film according to Examples 5 and 6 of the present invention.

FIG. 3 is a schematic cross section of a conventional apparatus used in a comparative experiment of forming a silicon film.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coating room 2 Film-forming room 3 Semiconductor raw material supply line 4 Gas supply line 5 Exhaust line 6 Heater 7 Spin coater 8 Substrate (base) 8a Coating surface 9 Silicon adhesion member 9a Material adhesion surface 10 Silicon adhesion member 10a Material adhesion surface 11 Gate valve 20 Silicon film forming device 30 Silicon film forming device

Claims (11)

[Claims] In a silicon film forming apparatus for forming a silicon film on a substrate by heating a substrate coated with a semiconductor raw material liquid by a heating means, the silicon film forming apparatus is disposed at a position facing a surface of the substrate coated with the semiconductor raw material liquid. A silicon film forming apparatus comprising: a silicon adhering member having a material adhering surface for adhering a semiconductor material vaporized from a coating surface by heating. 2. The method according to claim 1, wherein the semiconductor raw material liquid comprises only a liquid raw material or a raw material solution, and the raw material-adhering surface of the silicon-adhering member is at least heated to a predetermined distance from the semiconductor raw material liquid-coated surface of the substrate. 2. The silicon film forming apparatus according to claim 1, wherein the silicon film forming apparatus is formed so as to cover the base with an interval. 3. The silicon film forming apparatus according to claim 1, wherein the raw material adhering surface of the silicon adhering member is a plate-shaped or mesh-shaped member formed in a planar shape or a bowl shape. 4. The raw material attachment surface of the silicon attachment member is 5 to 5.
The silicon film forming apparatus according to any one of claims 1 to 3, wherein the silicon film forming apparatus faces the surface of the substrate to which the semiconductor raw material liquid is applied at an interval of 180 mm. 5. The method according to claim 1, wherein, when attaching the vaporized semiconductor material, the temperature of the silicon attachment member is set lower than the temperature of the semiconductor material liquid application surface of the substrate. The silicon film forming apparatus as described in the above. 6. The silicon film forming apparatus according to claim 1, wherein the raw material adhering surface has an area sufficient to project at least a projected shadow of the substrate. 7. A method for forming a silicon film on a substrate by applying a semiconductor raw material liquid onto the substrate and then heating the substrate to form a silicon film on the substrate, wherein the apparatus according to claim 1 is used. A method for forming a silicon film. 8. A semiconductor raw material liquid represented by the general formula Si_nR_mSy
_i(N is an integer of n ≧ 1 and R is each independently hydrogen, organic
Selected from the group consisting of bases. Sy is a silyl group, m + i
= 2n + 2, m is an integer of m ≧ 0, i is an integer of i ≧ 0)
Or Si_qR_tSy_w(Q is an integer of q ≧ 3, R is
Each is independently selected from the group consisting of hydrogen and organic groups. S
y is a silyl group, t + w = 2q, t is an integer of t ≧ 0, w is
w ≧ 0), and Si_nX_kH_j(X is haloge
Atom, k + j = 2n + 2, k is an integer of k ≧ 1, j is j
≧ 0, n is an integer of n ≧ 1) or Si_qX_yH
_z(X is a halogen atom, y + z = 2q, y is an integer of y ≧ 1)
Number, z is an integer of z ≧ 0, q is an integer of q ≧ 3)
The method for forming a silicon film according to claim 7, which is a compound. 9. The method according to claim 7, wherein the formation of the silicon film is performed in an inert gas atmosphere. 10. The method for forming a silicon film under a pressure of 10 kP.
The method for forming a silicon film according to claim 7, wherein the method is performed in an atmosphere gas of a or more. 11. The method for forming a silicon film according to claim 7, wherein the application of the semiconductor raw material liquid is performed on the substrate with a coating thickness of 1 μm or more.