JPH04252020A - Method and apparatus for formation of amorphous silicon thin film - Google Patents

Abstract

PURPOSE:To form an amorphous silicon thin film having an accurate composition at high speed by a method wherein, when the amorphous silin thin film is formed by evaporating or exciting silicon, by exciting hydrogen and by reacting them on a substrate, it is achieved that the evaporation means or the excitation means of the silicon and the excitation means of the hydrogen do not interfere with each other and individual raw materials are excited or activated independently to a desired state. CONSTITUTION:A shielding member 16 composed of a conductive material is installed between the excitation means, of silicon 5, which is composed of an electron-beam evaporation source 6 used to evaporate the silicon or of the evaporation source 6 and of an ionization means 7 and the excitation means 10 of hydrogen; a positive potential or a negative potential is applied to the shielding member 16. Thereby, both means are shielded electrically.

Description

[Detailed description of the invention]

0001

TECHNICAL FIELD The present invention relates to a method and an apparatus for forming a thin film of amorphous silicon, and particularly to a method for forming a thin film of amorphous silicon by depositing silicon and hydrogen particles on a substrate. The present invention relates to a method and apparatus for forming an amorphous silicon thin film.

0002

2. Description of the Related Art Plasma CVD (chemical vapor deposition) is known as a method for forming a thin film of amorphous silicon. This method enables thin film formation at a lower temperature than the conventional thermal CVD method by replacing part or most of the thermal energy required for the chemical reaction of raw material gases with electrical energy. It's a method. In this plasma CVD method, a raw material gas is supplied into a vacuum chamber, and direct current or high frequency is applied to cause glow discharge to generate plasma. Then, a thin film is formed on the surface of the substrate placed in the plasma. In this case, the raw material gas supplied into the chamber becomes active excited species such as ions, radicals, atoms, or molecules when passing through the plasma. Since the reaction of these excited species proceeds even at low temperatures, it is thought that a thin film of the compound is formed on the substrate at low temperatures. Therefore, this plasma CVD method has not only the advantage of the CVD method of being good at covering three-dimensional objects, but also the advantage of the PVD (physical vapor deposition) method of being able to form films at low temperatures. .

By the way, when producing amorphous silicon used for solar cells, photosensitive drums, etc., a high frequency plasma CVD method is usually used. This method not only enables low-temperature film formation as mentioned above, but also
It has various advantages such as easy multilayering, easy control of valence electrons, easy continuous automation, easy expansion into a large area, and low cost.

However, this high frequency plasma CVD
The major disadvantage of this method is that the deposition rate is slow. Research on high-speed film formation has been carried out in the past by searching for raw material gases and examining raw material supply methods, but currently only 1
The limit seems to be about 0 μm/hr. As for the cause, some think that it is an essential problem arising from the film formation method.

[0005] For these reasons, high frequency plasma CV
Amorphous silicon film forming methods using methods other than the D method are also being investigated. For example, there is a method of forming an amorphous silicon thin film using a PVD method such as a reactive vapor deposition method, a reactive sputtering method, or a reactive ion plating method. Reactive evaporation is a so-called vacuum evaporation method in which silicon is evaporated in a vacuum chamber by resistance heating evaporation or electron beam heating evaporation and deposited on a substrate to form a thin film. This is a method of forming a thin film of amorphous silicon. In addition, the reactive sputtering method uses plasma generated in a vacuum chamber to collide high-speed particles with the surface of a silicon target, and the particles that fly out from the target surface due to the sputtering phenomenon are deposited on the substrate. In a so-called sputtering method for forming a thin film, a thin film of amorphous silicon is formed by simultaneously introducing hydrogen. The reactive ion plating method is a reactive vacuum evaporation method in which a part or most of the silicon particles to be evaporated are excited and
This method forms an amorphous silicon thin film by ionizing it and depositing it on a substrate. However, these PVD methods have drawbacks in common, such as that it may be difficult to control the composition of amorphous silicon and that the film formation rate is relatively slow. Therefore, these methods are also practically difficult to apply.

By the way, one of the causes of the drawbacks of the PVD method is that hydrogen, which should react with silicon, is not excited. From this perspective, IVD (
Research using the ion-assisted vapor deposition method is also being conducted. The method is to form an amorphous silicon thin film by exciting and ionizing some or most of the hydrogen in a reactive vapor deposition method. However, conventionally,
In this IVD method as well, silicon was simply evaporated, similar to the reactive vapor deposition method. for that,
The energy of silicon particles is not sufficient, and the drawbacks of reactive deposition methods have not yet been completely eliminated.

[0007] From the above, we have reached the conclusion that both silicon and hydrogen should be excited or their energy should be increased. For example, by combining the reactive ion plating method and the IVD method, a part or most of the silicon is excited and ionized, and at the same time, a part or most of the hydrogen is also excited and ionized, and they are reacted to form a substrate. A possible method is to form an amorphous silicon thin film by depositing it on top. Furthermore, in the IVD method, it is conceivable to further increase the evaporation energy of silicon. By using such a method, it is expected that the amorphous silicon thin film will have excellent composition controllability and the possibility of high-speed formation.

[0008]

SUMMARY OF THE INVENTION However, the present inventors have found that the following problems occur when the various PVD methods that have been used in the past are operated simultaneously. In other words, in order to excite silicon and hydrogen, it is necessary to provide independent excitation means for each, but if they are operated at the same time, they interfere with each other and their independent operation becomes impossible. The problem is that there are cases. Furthermore, in order to increase the evaporation energy of silicon, it is effective to use the electron beam heating evaporation method and to strengthen the electron beam, but even in such a case, the hydrogen excitation means is affected. It becomes impossible to obtain stable operation.

[0009] The causes of this have not yet been completely elucidated at present. However, the following are estimated to be extremely important. That is, when silicon or hydrogen is excited, excitation or ionization using plasma is usually performed. Since electrons are also generated during ionization, ions and electrons are generated by the excitation. Some of these ions and electrons reach the substrate and participate in the formation of a thin film, while others exist in the vacuum chamber as stray electrons and stray ions. As a result, stray electrons and ions generated from one excitation means affect the other excitation means, and the independent operation of each excitation means is hindered. In order to increase the rate of formation of amorphous silicon thin films, it is necessary to increase the ionization rate and current density of each excitation method, but when attempting to do so, the tendency for mutual interference as described above increases. do. Furthermore, even when electron beam heating means is used to evaporate silicon, a large amount of reflected electrons will be generated if the power is increased. Therefore, it is thought that similar interference occurs.

[0010] Because of these problems, the method of forming an amorphous silicon thin film in which silicon and hydrogen are independently excited or activated to react as described above is practically impossible to apply. .

The present invention has been made in view of these circumstances, and its purpose is to enable silicon and hydrogen to be excited or activated independently and simultaneously to a desired state, The object of the present invention is to provide a method and apparatus for forming an amorphous silicon thin film that can speed up film formation and facilitate composition control.

0012

[Means for Solving the Problems] In order to achieve this object, the method for forming an amorphous silicon thin film according to the present invention involves evaporating silicon by an electron beam heating means and exciting hydrogen by an excitation means. When exciting hydrogen to a desired state using independent excitation means for each raw material, at least one electrical shield is provided between the silicon electron beam heating means or the excitation means and the hydrogen excitation means. The device is characterized in that the electron beam heating means and the hydrogen excitation means or the silicon and hydrogen excitation means are operated simultaneously by installing a member and applying a potential to the shielding member. The potential applied to the shielding member can be either a positive potential or a negative potential. In that case,
10 to 500V for positive potential, -10 for negative potential
It is desirable to set it as the range of -500V.

Further, the amorphous silicon thin film forming apparatus according to the present invention is provided with an electron beam heating means for evaporating silicon or an excitation means for exciting it and an excitation means for exciting hydrogen, which are independent from each other, and
At least one electrical shielding member made of a conductive material is installed between the electron beam heating means or the silicon excitation means and the hydrogen excitation means, and a DC power supply capable of applying a potential to the shielding member is provided. It is characterized by When exciting silicon, the excitation means includes, for example, a heating means such as resistance heating or electron beam heating to evaporate the silicon, and a glow discharge, arc discharge, or thermionic radiation to ionize at least a part of the evaporated particles. ionization means. It is desirable to use a mesh-like shielding member.

[0014]

[Operation] As described above, when various PVD methods are operated simultaneously using conventional methods, the respective excitation means may interfere with each other, making independent operation of each of them impossible. However, by installing at least one electrical shielding member between these excitation means and applying a potential to the shielding member, it is possible to independently excite silicon and hydrogen to a desired state. Become. The same applies when silicon is evaporated with high power by electron beam heating means. The reason for this is not necessarily clear, but when a shielding member to which a positive potential is applied is installed, stray electrons are captured by the shielding member, and stray ions are prevented from approaching the shielding member. This is thought to be because when a shielding member to which a negative potential is applied is installed, stray electrons are prevented from approaching the shielding member, and stray ions are captured by the shielding member. It is presumed that the effect of shielding stray electrons and ions prevents mutual interference between the respective excitation means. As a result of the inventors' experiments,
It has been found that the appropriate potential range to be applied to the shielding member is ±10 to ±500V. If the potential applied to the shielding member is less than ±10V, the above-mentioned interference prevention effect will not be sufficiently exhibited, and the same problems as in the prior art will occur. In addition, if the potential applied to the shielding member is ±500V or more, new practical problems will occur, such as abnormal discharge occurring between the shielding member and the excitation means, and it will be difficult to excite each raw material to the desired state. I become unable to do so.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing an embodiment of an amorphous silicon thin film forming apparatus according to the present invention.

As is clear from this figure, this amorphous silicon thin film forming apparatus 1 is equipped with a vacuum chamber 2 in the form of a closed container. The wall surface of the chamber 2 is made of a conductive material such as metal, and is maintained at ground potential. Further, the chamber 2 is provided with a vacuum exhaust port 3, and the chamber 2 is
The pressure inside is reduced.

An electron beam evaporation source 6 is provided at the bottom of the chamber 2 to evaporate silicon 5 by electron beam heating. Further, above the evaporation source 6, an arc discharge type ionization means 7 is provided which ionizes the evaporated particles 5a of the silicon 5 by arc discharge. The ionization means 7 includes an ionization electrode 8, and the excited state of the evaporated particles 5a is controlled by the magnitude of the voltage applied to the ionization electrode 8 from an excitation power source 9. Thus, in this example, silicon 5
is excited and ionized. That is,
Excitation means for the silicon 5 is constituted by an electron beam evaporation source 6, which is an electron beam heating means, and an arc discharge type ionization means 7.

The vacuum chamber 2 further includes an ion gun 1.
0 is set. A gas introduction pipe 13 provided with a valve 11 and a mass flow controller 12 is connected to the ion gun 10, and hydrogen gas 14 is supplied from the introduction pipe 13. Then, the hydrogen gas 14 is supplied to the excitation power source 1 within the ion gun 10.
5 and is excited and ionized, and is emitted as an ion beam 14a. That is, in this embodiment, the ion gun 10 serves as a means for exciting the hydrogen 14.

In this way, the excitation means for silicon 5 and the excitation means for hydrogen 14 are controlled independently.

A mesh-shaped shielding member 16 is disposed between the silicon 5 excitation means, that is, the electron beam evaporation source 6 and the ionization means 7, and the hydrogen 14 excitation means, the ion gun 10. The shielding member 16 is made of a conductive material such as metal, and is installed on the bottom surface of the chamber 2 with an insulating material 17 interposed therebetween. A DC power source 18 whose polarity can be switched is connected to the shielding member 16,
A positive potential or a negative potential is applied by the power source 18. In this way, the shielding member 16 electrically shields between the silicon 5 excitation means and the hydrogen 14 excitation means.

On the other hand, the top of the vacuum chamber 2 is located at a position where the evaporated particles 5a of silicon 5 excited by the arc discharge type ionization means 7 and the ion beam 14a of hydrogen 14 excited by the ion gun 10 are simultaneously projected. A substrate support electrode 20 is provided to support a substrate 19 that is a flat base. The substrate supporting electrode 20 has a built-in heater 21 for heating the substrate.
The heater 2 is powered by the heater power supply 22 connected to the
1 is activated, and the substrate 19 attached to the electrode 20 is heated. In addition, the substrate supporting electrode 2
A DC bias power supply 23 is connected to 0, and a negative bias potential is applied to the substrate 19 by the bias power supply 23. Furthermore, a high frequency power source 25 is connected to the substrate supporting electrode 20 via a matching box 24, and the high frequency power source 25 allows
A high frequency bias voltage is applied to the substrate 19.

Next, the operation of the amorphous silicon thin film forming apparatus 1 constructed as described above will be explained.

When a thin film of amorphous silicon is to be formed, a substrate 19 made of silicon or the like is attached to the substrate support electrode 20. Then, connect the vacuum pump 4 to the vacuum exhaust port 3 of the vacuum chamber 2, and
The chamber 2 is evacuated, and the heater 21 is activated by the heater power source 22 to heat the substrate 19 to a predetermined temperature. Further, a predetermined bias potential is applied to the substrate 19 by a DC bias power supply 23 or a high frequency power supply 25. Furthermore, the shielding member 16 is provided with a DC power source 1.
8, a positive potential or a negative potential is applied.

In this state, the electron beam evaporation source 6 is operated to evaporate the silicon 5, and the evaporated particles 5a are excited by the arc discharge type ionization means 7. Then, at least a portion of the evaporated particles 5a are ionized. The ions are then accelerated by the electric field between them and the substrate 19 and collide with the substrate 19. Meanwhile, at the same time, the ion gun 10 is operated to irradiate the substrate 19 with an ion beam 14a of hydrogen 14. Thereby, the excited hydrogen particles 14 collide with the substrate 19.

In this way, both the silicon 5 particles and the hydrogen 14 particles are guided to the surface of the substrate 19 in an excited state. Therefore, they react and particles of the compound are formed. The particles then adhere and accumulate on the surface of the substrate 19. As a result, a thin film of amorphous silicon is formed.

By the way, when silicon 5 is excited in this way, ions and electrons of silicon 5 are generated. Further, due to the excitation of the hydrogen 14, its ions and electrons are generated. Moreover, since the silicon 5 is heated and evaporated by the electron beam, if the electron beam is strengthened, a large amount of reflected electrons will be generated. If they stray, each excitation means will be affected. For example, when ions and electrons generated by excitation of silicon 5 fly into the ion gun 10,
The normal operation of the ion gun 10 is hindered, and the hydrogen 14 is no longer excited to the desired state. Further, a similar phenomenon occurs when electrons generated from the electron beam evaporation source 6 that heats and evaporates the silicon 5 jump into the ion gun 10. In this way, silicon 5 excitation means and hydrogen 1
If the four excitation means are operated simultaneously, they may interfere with each other, making it impossible to operate each of them independently.

However, in the case of this amorphous silicon thin film forming apparatus 1, a shielding member 16 made of a conductive material is provided between the silicon 5 excitation means and the hydrogen 14 excitation means, and the shielding member 16 has a positive polarity. Alternatively, since a negative potential is applied, such mutual interference is prevented. For example, if a positive potential is applied to the shielding member 16,
Stray electrons are captured by the shielding member 16, and stray ions are repelled by the shielding member 16. Further, when a negative potential is applied to the shielding member 16, stray ions are captured by the shielding member 16, and stray electrons are repelled. As a result, these stray electrons and ions are prevented from affecting the other excitation means.

By thus preventing mutual interference between the excitation means for silicon 5 and the excitation means for hydrogen 14, they can be operated simultaneously and independently, bringing silicon 5 and hydrogen 14 into desired states, respectively. Since it becomes possible to excite, it becomes possible to accurately control the composition of the amorphous silicon thin film that is formed. Furthermore, since the excitation energy can be increased, high-speed film formation is also possible.

Furthermore, by using the mesh-like shielding member 16, the shielding member 16 becomes less of a physical barrier to the evaporated particles 5a of silicon 5 and the ion beam 14a of hydrogen 14, so that the shielding member 16 can be reduced. Member 16
Even if the height is increased, a chemical reaction can be caused over a wide range on the substrate 19 to form an amorphous silicon thin film. By increasing the height of the shielding member 16 in this manner, mutual interference between the respective excitation means can be more reliably prevented.

Similar effects can be obtained by providing the shielding member 16 even when the power of the electron beam evaporation source 6 is increased to simply evaporate the silicon 5 without ionizing it to form a thin film of amorphous silicon.

[0031] Such an amorphous silicon thin film forming apparatus 1 was actually manufactured as a prototype, and the following experiments were conducted using it.

[0032] On the substrate supporting electrode 20, a 50 mm long and 50 mm wide
A silicon substrate 19 with a thickness of 1 mm and a thickness of 1 mm was attached. Then, the inside of the vacuum chamber 2 is pumped by the vacuum pump 4.
The pressure was reduced to ×10 −7 Torr. In addition, the heater 21
The temperature of the substrate 19 was set to 400° C., and a bias potential of −100 V was applied to the substrate 19 by the DC bias power supply 23. On the other hand, a positive potential of 100 V was applied to the shielding member 16 by the DC power supply 18. In this state, the electron beam evaporation source 6 and arc discharge type ionization means 7 were operated to perform ion plating of silicon. At the same time, hydrogen gas 14 was supplied to the ion gun 10, and the ion gun 10 was operated to irradiate the substrate 19 with ionized hydrogen. As a result, a thin film was formed on the surface of the substrate 19.

At this time, the electron beam evaporation source 6 and ionization means 7, which are excitation means for silicon 5, and the ion gun 10, which is excitation means for hydrogen 14, operate normally.
No abnormalities such as interference were observed.

Next, the substrate 19 with the thin film formed on its surface in this manner was taken out from the chamber 2, and an evaluation test was conducted on the thin film. The formed thin film was confirmed to be amorphous by XRD (X-ray diffraction). Furthermore, it was confirmed by SIMS that the hydrogen content in the silicon of the thin film was 13%. From the results of the film thickness measurement, the film formation rate was calculated to be approximately 20 μm/hr. Note that film formation was performed 10 times under the same conditions, and the reproducibility was good.

Next, by switching the polarity of the DC power supply 18,
A similar experiment was conducted by applying a negative potential of -100V to the shielding member 16. At this time, exactly the same results as when a positive potential was applied to the shielding member 16 were obtained.

On the other hand, using the same device 1, the shielding member 1
A thin film formation test was conducted with No. 6 removed. In this case as well, film formation was performed 10 times under the same conditions. In this case, the ion gun 10 often became uncontrollable during thin film formation. After the thin film formation was completed, the substrate 19 was taken out from the chamber 2 and an evaluation test was performed.The formed thin film was all identified as amorphous by XRD, but the hydrogen content measured by SIMS was
It varied between 5 and 10%. Further, as a result of measuring the film thickness, a variation of about 10 to 15 μm/hr was observed in the film formation rate.

Furthermore, with the operation of the arc discharge type ionization means 7 stopped, the power of the electron beam evaporation source 6 was increased, and similar film formation experiments were conducted with and without the shielding member 16 installed. I did it. As a result, it was confirmed that the operation of the ion gun 10 becomes unstable when the shielding member 16 is not present, but when the shielding member 16 is installed, an amorphous silicon thin film can be formed satisfactorily.

As for the excitation means for the silicon 5, in addition to the combination of the electron beam evaporation source 6 and the arc discharge type ionization means 7 as in the above embodiment, resistance heating evaporation, glow discharge, arc discharge, and thermionic radiation can be used. Similar results can be obtained when using a combination of at least one of the following, or a combination of electron beam heating evaporation with at least one of glow discharge, arc discharge, and thermionic radiation, and even when sputtering is used. It has been confirmed that it can be obtained. Furthermore, similar results were obtained when at least one of glow discharge, arc discharge, thermionic radiation, and ion gun was used as the means for exciting hydrogen 14.

FIG. 2 is a schematic diagram showing a different embodiment of the amorphous silicon thin film forming apparatus according to the present invention. In this embodiment, parts corresponding to those in the embodiment of FIG. 1 are denoted by the same reference numerals, and redundant explanation will be omitted.

This amorphous silicon thin film forming apparatus 1
In this case, silicon 5 is used as an excitation means for silicon 5.
a resistance heating evaporation source 26 that evaporates the silicon 5, and a glow discharge type ionization means 2 that ionizes the evaporated particles 5a of the silicon 5.
7 is used. The ionization means 27 includes an ionization electrode 28, and the excited state of the evaporated particles 5a is controlled by the magnitude of the voltage applied to the ionization electrode 28 from an excitation power source 29.

The interior of the vacuum chamber 2 is divided into an upper vapor deposition chamber 32 and a lower vapor deposition chamber 33 by a partition wall 31 having a small opening 30 in the center. The resistance heating evaporation source 26 is installed in the evaporation chamber 33 in the lower part thereof. Further, the glow discharge type ionization means 27 is arranged in the upper vapor deposition chamber 32.

[0042] In the vapor deposition chamber 32, an ion gun 10, which is a means for exciting hydrogen 14, is further provided. This ion gun 10 is capable of operating under higher pressure than the embodiment shown in FIG.

A double plate-shaped shielding member 16 is provided between the silicon 5 excitation means and the hydrogen 14 excitation means. These shielding members 16, 16 are both made of conductive material, and are connected to the partition wall 3 through an insulating material 17.
It is installed on 1. And those shielding members 16
, 16 are applied with different positive or negative potentials by DC power supplies 18, 18, respectively.

The vacuum chamber 2 is provided with a vacuum exhaust port 3 that opens into the evaporation chamber 33 at the bottom and a vacuum exhaust port 34 that opens into the vapor deposition chamber 32 at the top. A vacuum pump 4 is connected to the vacuum exhaust port 34 via a valve 35, and the vacuum pump 4 operates the deposition chamber 32 and the evaporation chamber 3.
3 are both evacuated.

The rest of the structure is the same as the embodiment shown in FIG.

In the amorphous silicon thin film forming apparatus 1 configured as described above, the valve 35 is opened to operate the vacuum pump 4 to reduce the pressure in both the deposition chamber 32 and the evaporation chamber 33, and then the valve 35 is closed to further vacuum the chamber. When the pump 4 is operated, the pressure in the evaporation chamber 33 becomes sufficiently lower than that in the deposition chamber 32. Therefore, when the resistance heating evaporation source 26 is operated in this state, the silicon 5 is efficiently evaporated. The evaporated particles 5a of the silicon 5 thus evaporated flow into the deposition chamber 32 through the opening 30 of the partition wall 31, are ionized by the glow discharge type ionization means 27, and collide with the substrate 19. In this case, since the pressure within the vapor deposition chamber 32 is kept relatively high, glow discharge can also be caused efficiently. On the other hand, the hydrogen 14 is excited and ionized by the ion gun 10, and the substrate 19 is irradiated with the ion beam 14a. In this way, in this amorphous silicon thin film forming apparatus 1 as well, silicon 5 and hydrogen 1 are formed on the substrate 19, as in the embodiment of FIG.
A thin film of amorphous silicon, which is a compound with 4, is formed.

During this period, the ions and electrons generated by the glow discharge type ionization means 27 or the ions and electrons generated by the ion gun 10 are exposed to the shielding member 16 provided between them, as in the embodiment of FIG.
16. Therefore, these ions or electrons are prevented from influencing the other excitation means. Moreover, in the case of this embodiment, the shielding members 16 are arranged in duplicate and potentials of different magnitudes are applied to them, so the potential applied to one shielding member 16 is set to be higher. However, the potential difference between the excitation means for silicon 5 or the excitation means for hydrogen 14 and the shielding member 16 adjacent thereto can be made small. Therefore, while increasing the electrical shielding effect of the shielding member 16, it is possible to prevent abnormal discharge or the like from occurring between the shielding member 16 and the excitation means. If the number of shielding members 16 is increased, the potential applied to the shielding members 16 remote from the excitation means can be further increased, and the electrical shielding between the respective excitation means can be further ensured.

Note that in the above embodiment, the shielding member 1
Although the shielding member 6 is in the form of a mesh or a flat plate, the shielding member 16 may be of any shape, such as a block or a curved surface. Further, the voltage waveform of the potential applied to the shielding member 16 can also be any arbitrary waveform, such as a continuous wave, a rectangular wave, or a triangular wave.

Furthermore, the substrate on which the amorphous silicon thin film is formed is not limited to the flat substrate 19 as in the above embodiment, but the present invention can also be used when forming the amorphous silicon thin film on a three-dimensional object such as a rod shape. can be applied.

[0050]

As is clear from the above description, according to the present invention, when forming a thin film of amorphous silicon from silicon and hydrogen, a means for excitation of the silicon or an electron beam heating means for vaporizing the silicon can be used. Since a shielding member to which a positive or negative potential is applied is installed between the hydrogen excitation means, the shielding member to which a positive or negative potential is applied is installed between the excitation means or between the silicon electron beam heating means and the hydrogen excitation means. interference can be prevented. Therefore, while operating these excitation means and electron beam heating means simultaneously, it is possible to excite or activate silicon and hydrogen to the desired state independently, and the composition of the amorphous silicon thin film can be precisely controlled. At the same time, it becomes possible to speed up the film formation.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of an amorphous silicon thin film forming apparatus according to the present invention.

FIG. 2 is a schematic configuration diagram showing another embodiment of the amorphous silicon thin film forming apparatus according to the present invention.

[Explanation of symbols]

1 Amorphous silicon thin film forming apparatus 2 Vacuum chamber 3 Vacuum exhaust port 4 Vacuum pump (vacuum exhaust means) 5 Silicon 6 Electron beam evaporation source (electron beam heating means) 7
Arc discharge type ionization means (silicon excitation means) 10
Ion gun (hydrogen excitation means) 14 Hydrogen 16 Shielding member 18 DC power supply 19 Substrate (substrate) 20 Substrate support electrode 26 Resistance heating evaporation source (heating means) 27 Glow discharge type ionization means (silicon excitation means) 30 Opening 31 Partition wall 32 Evaporation chamber 33 Evaporation chamber

Claims (12)

[Claims] 1. A method for forming an amorphous silicon thin film, in which silicon is evaporated by an electron beam heating means, hydrogen is excited by a hydrogen excitation means, and a thin film of amorphous silicon is formed by adhering the silicon and hydrogen to a substrate. ; installing at least one electrical shielding member between the electron beam heating means and the hydrogen excitation means, applying a potential to the shielding member, and simultaneously operating the electron beam heating means and the hydrogen excitation means; A method for forming an amorphous silicon thin film, the method comprising: 2. A method for forming an amorphous silicon thin film in which an amorphous silicon thin film is formed by exciting silicon and hydrogen using independent excitation means and adhering them to a substrate; A method for forming an amorphous silicon thin film, the method comprising: installing at least one electrical shielding member between the shielding member and the excitation means; applying a potential to the shielding member; and simultaneously operating the excitation means. 3. The method of forming an amorphous silicon thin film according to claim 1, wherein a positive potential of 10 to 500 V is applied to the shielding member. 4. The method of forming an amorphous silicon thin film according to claim 1, wherein a negative potential of -10 to -500 V is applied to the shielding member. 5. The amorphous silicon thin film according to claim 1, wherein at least one of glow discharge, arc discharge, thermionic radiation, or an ion gun is used as the hydrogen excitation means. Formation method. 6. The amorphous silicone according to claim 2, wherein a combination of resistance heating evaporation, glow discharge, arc discharge, or thermionic radiation is used as the silicon excitation means. Method of forming silicon thin film. 7. The silicon excitation method according to claim 2, wherein a combination of electron beam heating evaporation and at least one of glow discharge, arc discharge, and thermionic radiation is used as the silicon excitation means. Method for forming amorphous silicon thin film. 8. The method for forming an amorphous silicon thin film according to claim 2, wherein a sputtering method is used as the silicon excitation means. 9. An amorphous silicon thin film forming apparatus that forms an amorphous silicon thin film by evaporating silicon, exciting hydrogen, and attaching the silicon and hydrogen particles to a substrate; an electron beam heating means for evaporating, a hydrogen excitation means for exciting the hydrogen, and at least one electrical shielding member made of a conductive material provided between the electron beam heating means and the hydrogen excitation means; An apparatus for forming an amorphous silicon thin film, comprising: a DC power source that applies a potential to the shielding member. 10. An amorphous silicon thin film forming apparatus that forms an amorphous silicon thin film by exciting silicon and hydrogen to desired states and attaching their particles to a substrate; mutually independent excitation means for exciting each, at least one or more electrical shielding members made of a conductive material provided between the excitation means;
An apparatus for forming an amorphous silicon thin film, comprising: a DC power source that applies a potential to the shielding member. 11. The amorphous silicon thin film forming apparatus according to claim 9, wherein the shielding member has a mesh shape. 12. The excitation means for silicon comprises a heating means for vaporizing the silicon and a glow discharge type ionization means for ionizing at least a part of the vaporized particles, and the heating means is arranged such that the substrate is placed on the substrate. 11. The amorphous silicon thin film forming apparatus according to claim 10, wherein the evaporation chamber is provided within an evaporation chamber partitioned by a partition wall having an opening, and a vacuum evacuation means is connected to the evaporation chamber.