JPH08157295A - Formation of thin film - Google Patents

Abstract

PURPOSE: To form plural layers of thin films varying crystal structures and crystal bearings, etc., at a low temp. CONSTITUTION: A substrate 11 is placed on a sample stage 10 installed in a reaction chamber 8 subjected to vacuum evacuation. This sample stage 10 is freely rotatable and tiltable by the action of a driving device 35. Reactive gases selected by a gas selector 34 are supplied onto the substrate 11 and a gas selected by selector 32 is cast as a beam onto the substrate 11 by the action of an ECR ion generator 2. While substance is deposited by the plasma CVD reaction of the reactive gases on the substrate 11, the substance is subjected to irradiation with the beam of the gas of the low energy to the extent not inducing sputtering from the prescribed direction determined by the posture of the sample stage 10. Consequently, the successively deposited substance is easily crystallized at a relatively low temp. below the crystallization temp. Any of polycrystals, axially oriented polycrystals and single crystal are obtainable by the directions where the substrate is irradiated with the beam.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention makes it possible to easily form a thin film having various desired crystal structures such as single crystal, polycrystal, axially oriented polycrystal and amorphous at relatively low temperature. The present invention relates to a thin film forming method.

[0002]

2. Description of the Related Art As a method of forming a thin film of a predetermined substance on a substrate at a relatively low temperature, a plasma chemical vapor deposition method (plasma CVD) in which a reaction gas is put into a plasma state to cause a chemical reaction is well known. ing. Many types of films can be formed at low temperature, weak heat resistance, generally cheap substrate can be used, and it has the advantage that it is less likely to cause pollution etc. because it is at low temperature. Therefore, the use of plasma CVD is expanding mainly in the semiconductor related industry.

[0003]

However, in general low temperature plasma CVD, the formed thin film is almost always amorphous, and the electrical characteristics such as carrier mobility and the optical characteristics. In most cases, it is inferior to the single crystal thin film or the polycrystalline thin film.

Therefore, if a single crystal thin film or a polycrystalline thin film can be formed at a temperature as low as that in the conventional amorphous thin film formation, its application is expected to be wide-ranging mainly in the semiconductor related industry. To be done.

According to the present invention, a polycrystal thin film or a polycrystal film in which one crystal axis of the polycrystal is oriented in one direction on a substrate having an arbitrary crystal structure at a temperature as low as the conventional amorphous thin film formation. It is an object of the present invention to provide a thin film forming method for forming an axially oriented polycrystalline film, which is superior in electrical characteristics and the like to a normal polycrystalline thin film, and a single crystal thin film.

Another object of the present invention is to provide a thin film forming method for forming an amorphous thin film such as a high quality amorphous film.

[0007]

The thin film forming method of the first invention is a thin film forming method for forming a polycrystalline thin film of a predetermined substance on a substrate, wherein crystallization of the predetermined substance does not occur. In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature, a beam of a low energy gas that does not cause the predetermined substance to cause sputtering. Are radiated onto the substrate from arbitrary plural directions.

The thin film forming method of the second invention comprises:
A thin film forming method for forming a polycrystalline thin film of a predetermined substance, wherein an amorphous thin film of the predetermined substance is formed on the substrate in advance, and a low temperature at which crystallization of the predetermined substance does not occur. Below, the amorphous thin film is irradiated with a beam of gas having a low energy to such an extent that the predetermined substance does not cause sputtering from arbitrary plural directions.

The thin film forming method of the third invention comprises:
A thin film forming method for forming an axially oriented polycrystalline thin film of a predetermined substance, wherein the predetermined substance is provided by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance does not occur. In the process of depositing the substrate on the substrate, a beam of low energy gas that does not cause the predetermined substance to sputter is irradiated onto the substrate from one direction.

The thin film forming method according to the fourth aspect of the present invention comprises:
A thin film forming method for forming an axially oriented polycrystalline thin film of a predetermined substance, comprising preliminarily forming an amorphous thin film or a polycrystalline thin film of the predetermined substance on the substrate, and crystallizing the predetermined substance. Under a low temperature at which the amorphous substance or the polycrystalline thin film is irradiated from one direction with a low energy gas beam that does not cause sputtering of the predetermined substance.

The thin film forming method according to the fifth invention comprises:
A thin film forming method for forming an amorphous thin film of a predetermined substance, wherein the predetermined substance is supplied by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance does not occur. In the process of depositing on the substrate, the substrate is irradiated with a beam of gas having low energy to such an extent that rearrangement of atoms constituting the predetermined substance does not occur.

The thin film forming method according to the sixth invention comprises:
A thin film forming method for forming a thin film including a plurality of layers having different crystal structures, characterized in that at least two or more of the following steps (a) to (d) are sequentially performed: Here, in the steps (a) to (d), (a) the predetermined gas is supplied onto the substrate under a low temperature at which crystallization of a predetermined material forming one layer does not occur. In the process of depositing a substance on the substrate, a beam of low energy gas that does not cause the predetermined substance to sputter is irradiated onto the substrate from arbitrary plural directions. Forming a polycrystalline thin film of material;
(b) in the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate under a low temperature at which crystallization of the predetermined substance forming one layer does not occur, A step of irradiating the substrate with a beam of gas having low energy such that the predetermined substance does not cause sputtering from one direction, and as a result, forming an axially oriented polycrystalline thin film of the predetermined substance; (c) In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur, the predetermined substance is deposited on the substrate. A low energy gas beam that does not cause the substance to sputter,
Irradiating the substrate from a plurality of directions perpendicular to a plurality of close-packed planes of the single crystal thin film of the predetermined substance to be formed, thereby forming the single crystal thin film of the predetermined substance; and And (d) a step of forming an amorphous thin film of the predetermined substance by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur. .

The thin film forming method according to the seventh invention comprises:
A thin film forming method for forming a thin film containing a plurality of single crystal layers having different crystal orientations or a plurality of axially oriented polycrystal layers, wherein a plurality of steps are allowed from the following steps (a) to (d). Sequentially, wherein the steps (a) to (d) include (a) applying a reaction gas onto the substrate under a low temperature at which crystallization of a predetermined material forming one layer does not occur. In the process of depositing the predetermined substance on the substrate by supplying the gas, a beam of gas with low energy such that the predetermined substance does not cause sputtering is irradiated onto the substrate from arbitrary plural directions. And, as a result, forming a polycrystalline thin film of the predetermined substance; (b) supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur. In the process of depositing the predetermined substance on the substrate by A low-energy gas beam that does not cause sputtering to irradiate the substrate from one direction, and as a result, forms an axially oriented polycrystalline thin film of the predetermined substance; (c) one layer In a process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance does not occur, the predetermined substance causes sputtering. A low energy beam of gas that does not cause irradiation is irradiated onto the substrate from a plurality of directions perpendicular to a plurality of close-packed planes of a single crystal thin film of the predetermined substance to be formed, and as a result, the predetermined beam is irradiated. Forming the single crystal thin film of substance; and (d) supplying the reaction gas onto the substrate under a low temperature at which crystallization of one layer of the substance does not occur. Amorphous substance A step of forming a film, said plurality of steps, the step
At least one of (b) and (c) is redundantly included, and the beam direction is different between the overlapping steps.

The thin film forming method of the eighth invention comprises:
A thin film forming method for forming a thin film including a plurality of layers of different substances, wherein a plurality of steps are performed while allowing duplication among the following steps (a) to (d), wherein the steps (a) to (d) (a) depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur. In the process, a low energy gas beam that does not cause sputtering of the predetermined substance is irradiated onto the substrate from arbitrary plural directions, and as a result, a polycrystalline thin film of the predetermined substance is formed. (B) In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur. At a low energy level such that the predetermined substance does not cause sputtering. Irradiating the substrate with the gas beam from one direction, thereby forming an axially oriented polycrystalline thin film of the predetermined substance; (c) crystallization of one layer of the predetermined substance occurs. In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature, a gas with low energy such that the predetermined substance does not cause sputtering. A beam is irradiated onto the substrate from a plurality of directions perpendicular to a plurality of close-packed planes of a single crystal thin film of the predetermined substance to be formed, and as a result, the single crystal thin film of the predetermined substance is formed. And (d) forming an amorphous thin film of the predetermined substance by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur. And the plurality of steps are Type of reaction gas is characterized in that it comprises two or more different steps.

The thin film forming method of the ninth invention is the method of the eighth invention, wherein in the two or more steps in which the kinds of the reaction gases are different, the substances deposited by the respective reaction gases are insulators, semiconductors, To be one of the conductors,
It is characterized in that the type of each reaction gas is selected.

The thin film forming method of the tenth invention is a thin film forming method for forming a thin film including a plurality of layers having different added impurities on a substrate, wherein the following steps (a) to (d) are repeated. To perform a plurality of steps, wherein the steps (a) to (d) are performed.
(A) In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur. Then, a step of irradiating the substrate with a low energy gas beam of such a degree that the predetermined substance does not cause sputtering from arbitrary plural directions, and as a result, forming a polycrystalline thin film of the predetermined substance; b) In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur, A step of irradiating the substrate with a low-energy gas beam that does not cause sputtering of a predetermined substance from one direction, and as a result, forming an axially oriented polycrystalline thin film of the predetermined substance; One layer of a given substance In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization does not occur, the predetermined substance may have a temperature low enough to prevent sputtering. Irradiating a beam of gas of energy onto the substrate from a plurality of directions perpendicular to a plurality of close-packed planes of a single crystal thin film of the predetermined substance to be formed, and as a result, the single crystal of the predetermined substance. Forming a thin film; and (d) supplying a reaction gas onto the substrate at a low temperature at which crystallization of one layer of a predetermined substance does not occur, and thereby the predetermined substance is amorphous. It is a step of forming a thin film, and the plurality of steps include two or more steps in which an impurity element added to the reaction gas is different.

The thin film forming method according to the eleventh invention is the method according to any one of the sixth to tenth inventions, wherein the step (d) comprises (c-4-1) crystallization of the predetermined substance. Under a low temperature that does not occur, the step of depositing the predetermined substance on the substrate by supplying the reaction gas onto the substrate, (c-4-2) step (c-4-1) ) Is performed, and a step of irradiating the substrate with a beam of gas having low energy to such an extent that rearrangement of atoms constituting the predetermined substance does not occur.

The thin film forming method of the twelfth invention is characterized in that, in the method of the second invention or the fourth invention, the low temperature is not lower than the Debye temperature of the predetermined substance.

The thin film forming method of the thirteenth invention is a thin film forming method of forming a single crystal thin film of a predetermined substance on a substrate, wherein an amorphous thin film and a polycrystal of the predetermined substance are formed on the substrate. A thin film or an axially oriented polycrystalline thin film is formed in advance, and the predetermined substance is sputtered within a temperature range in which crystallization of the predetermined substance does not occur and at a temperature higher than the Debye temperature of the predetermined substance. A low energy gas beam that does not cause a beam of the amorphous thin film, the polycrystalline thin film, or the axially oriented polycrystalline thin film from a plurality of directions perpendicular to the plurality of close-packed planes of the single crystalline thin film to be formed. It is characterized by irradiation to the top.

The thin film forming method of the fourteenth invention is characterized in that, in any one of the first to thirteenth inventions, the gas is an inert gas.

The thin film forming method of the fifteenth invention is the method of the fourteenth invention, wherein the atomic weight of the element forming the inert gas is the element forming the predetermined substance irradiated with the beam of the gas. It is characterized by not exceeding the maximum atomic weight.

A thin film forming method of a sixteenth invention is the method of the fifteenth invention, wherein the atomic weight of the element constituting the inert gas does not exceed the maximum atomic weight of the element constituting the predetermined substance, and , And is the closest atomic weight.

A thin film forming method according to a seventeenth invention is the method according to any one of the first to sixteenth inventions, characterized in that the gas is a gas substance containing an element constituting the predetermined substance. And

A thin film forming method of an eighteenth invention is the method of any one of the first to seventeenth inventions, wherein the reaction gas contains a gaseous substance containing an impurity element to be added to the predetermined substance. Is characterized by.

The thin film forming method according to the nineteenth invention is the method according to any one of the sixth to eleventh inventions, wherein the thin film including the plurality of layers is formed while maintaining the low temperature at a constant value. Is characterized by.

A thin film forming method of a twentieth invention is the method of the first, second or fifth invention, wherein a reflector for focusing the gas beam on the substrate is arranged around the substrate. At the same time, the irradiation of the gas beam is performed.

The thin film forming method of the twenty-first invention is the method of the sixth invention to the eleventh invention, wherein the beam of gas is directed onto the substrate when the step (a) or (d) is executed. Irradiation with the beam of the gas is performed while a reflection plate for converging is arranged around the substrate.

The thin film forming method of the twenty-second invention is the method of the twentieth or twenty-first invention, wherein at least the surface of the reflecting plate which is irradiated with the gas beam causes sputtering due to the irradiation of the gas beam. It is characterized by being made of a non-material.

The thin film forming method of the twenty-third invention is the method of the twentieth or twenty-first invention, wherein at least the surface of the reflection plate which is irradiated with the gas beam constitutes the uppermost substance on the substrate. It is characterized in that it is composed of an element.

The thin film forming method according to the twenty-fourth invention is the method according to any one of the sixth through eleventh inventions, wherein each of the steps (a) to (d) is performed when the beam of gas is irradiated. ,
It is characterized in that the beam of gas is irradiated onto the substrate with low energy such that none of the layers already formed on the substrate cause sputtering.

A thin film forming method of a twenty-fifth invention is the method of any of the sixth to eleventh inventions, wherein the predetermined substance is deposited in each of the steps (a) to (d). Previously, the gas beam is irradiated onto the substrate.

The thin film forming method according to the twenty-sixth invention is the method according to any one of the first to twenty-fifth inventions, wherein plasma is generated using microwaves and the plasma is guided to the substrate by a divergent magnetic field. It is characterized in that a beam of the gas is obtained by a plasma irradiation device.

The thin film forming method of the 27th invention is the method of the 26th invention, wherein the substrate is made of a conductive material.
Moreover, the potential of the substrate is set to a desired value.

The thin-film forming method of the twenty-eighth invention is the method of the twenty-sixth invention, wherein the electrons generated by the plasma irradiation apparatus that can substantially contribute to the generation of the plasma sheath on the substrate. It is characterized in that an electron blocking member is used to prevent the particles from flying onto the substrate.

The thin film forming method of the twenty-ninth invention is characterized in that, in the method of the first or third invention, the low temperature is not lower than the Debye temperature of the predetermined substance.

The thin film forming method of the thirtieth invention is a thin film forming method of forming a single crystal thin film of a predetermined substance on a substrate, within the temperature range in which the crystallization of the predetermined substance does not occur. The degree to which the predetermined substance does not cause sputtering during the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a temperature higher than the Debye temperature of the predetermined substance. And irradiating the low energy gas beam onto the substrate from a plurality of directions perpendicular to a plurality of close-packed planes of the single crystal thin film to be formed.

The thin film forming method according to the thirty-first invention is the method according to any one of the sixth to eleventh inventions, wherein the low temperature in each of the steps (a) to (c) is the predetermined substance. It is characterized by being at or above the Debye temperature.

A thin film forming method of a thirty-second invention is the method of the first or third invention, wherein the predetermined substance is silicon, the reaction gas contains silane gas as a main component, and the low temperature is used. Is 400 ° C. or higher.

The thin film forming method of the 33rd invention is a thin film forming method for forming a single crystal thin film of silicon on a substrate, which is within a temperature range in which crystallization of silicon does not occur and at a temperature of 400 ° C. or more. In the process of depositing silicon on the substrate by supplying a reaction gas containing silane gas as a main component to the substrate, a beam of a gas having low energy such that silicon does not cause sputtering, Irradiation onto the substrate is performed from a plurality of directions perpendicular to a plurality of densest planes of the single crystal thin film to be formed.

A thirty-fourth invention is a method for forming a thin film according to any of the sixth invention to the eleventh invention, wherein the predetermined substance is used in at least one of the steps (a) to (c). Is silicon, the reaction gas contains silane gas as a main component, and the low temperature is 400
It is characterized by being at least ° C.

In the present invention, the "substrate" is not limited to an object as a simple base provided only for forming a thin film on the substrate, and includes, for example, a device having a predetermined function. And the medium on which the thin film is formed.

In the present invention, the "gas beam" means
This is a concept that includes any of a beam-like ion flow, an atomic flow, and a molecular flow.

[0043]

[Action]

<Operation of Method of First Invention> In the method of the first invention,
By irradiating the substrate with a beam of gas at a low temperature at which the prescribed substance does not crystallize while depositing the prescribed substance on the substrate, the densest crystal plane of the prescribed substance is directed in the beam direction. Crystallization progresses vertically. Moreover,
Since the direction of the beam is arbitrary plural directions, a polycrystalline thin film is generally formed.

<Operation of the method of the second invention> In the method of the second invention, an amorphous thin film of a predetermined substance is formed on the substrate in advance, and thereafter, the low temperature at which the predetermined substance is not crystallized. By irradiating the substrate with a beam of gas below, crystallization proceeds so that the densest crystal plane of a given substance is perpendicular to the beam direction. Moreover, since the beam direction is arbitrary plural directions, a polycrystalline thin film is generally formed.

<Operation of the method of the third invention> In the method of the third invention, while depositing a predetermined substance on the substrate, a beam of gas is generated at a low temperature at which the predetermined substance does not crystallize. By irradiating the substrate with crystallization, crystallization proceeds so that the densest crystal plane of a given substance is perpendicular to the beam direction. Moreover, since the beam is unidirectional, an axially oriented polycrystalline thin film is formed.

<Operation of the method of the fourth invention> In the method of the fourth invention, an amorphous thin film or a polycrystalline thin film of a predetermined substance is formed in advance on a substrate, and then the predetermined substance is crystallized. By irradiating the substrate with a gas beam at a low temperature that does not cause crystallization, crystallization proceeds so that the densest crystal plane of a given substance is perpendicular to the beam direction. Moreover, since the beam is unidirectional, an axially oriented polycrystalline thin film is formed.

<Operation of the Method of the Fifth Invention> In the method of the fifth invention, in the process of depositing the predetermined substance at a low temperature at which crystallization does not occur, the atoms constituting the predetermined substance are regenerated. A substrate is irradiated with a low energy gas beam that does not cause alignment. Therefore, crystallization is not promoted by the gas beam, and hydrogen atoms taken in as impurities in the predetermined substance that is being deposited are removed by sputtering with the gas beam. as a result,
Formation of an amorphous thin film proceeds efficiently.

<Operation of the Method of the Sixth Invention> In the method of the sixth invention, a thin film having a plurality of layers having different crystal structures is formed at a relatively low temperature. Moreover, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained.

<Operation of the Method of the Seventh Invention> In the method of the seventh invention, a plurality of single crystal layers having different crystal orientations or a plurality of axially oriented polycrystal layers are formed by changing the direction of the gas beam. A thin film having is formed. Moreover, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained.

<Operation of the Method of the Eighth Invention> In the method of the eighth invention, a thin film having a plurality of layers of different substances is formed by changing the kind of the reaction gas. Moreover, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained.

<Operation of Method of Ninth Invention> In the method of the ninth invention, a thin film having a plurality of layers of an insulator, a semiconductor, or a conductor is formed by appropriately selecting a reaction gas. Moreover, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained.

<Operation of the method of the tenth aspect of the invention> In the method of the tenth aspect of the invention, the type of the impurity element added to the reaction gas is made different to form a thin film having a plurality of layers having different added impurities. . Moreover, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained.

<Operation of the method of the eleventh invention> In the method of the eleventh invention, during the process of depositing a predetermined substance at a low temperature at which crystallization does not occur in forming an amorphous layer. Then, the substrate is irradiated with a beam of gas having a low energy to such an extent that rearrangement of atoms constituting a predetermined substance does not occur.
Therefore, crystallization is not promoted by the gas beam, and hydrogen atoms taken in as impurities in the predetermined substance that is being deposited are removed by sputtering with the gas beam. As a result, the predetermined substance is efficiently formed as an amorphous thin film.

<Operation of the method of the twelfth invention> In the method of the twelfth invention, since the temperature at the time of irradiating the beam of gas is kept above the Debye temperature of the predetermined substance, the predetermined substance is polycrystalline. Or the axial orientation polycrystallization progresses efficiently.

<Operation of the method of the thirteenth invention> In the method of the thirteenth invention, an amorphous thin film or the like of a predetermined substance is formed on a substrate in advance, and thereafter, a predetermined substance is not crystallized. By irradiating the substrate with a gas beam at a temperature, crystallization proceeds so that the densest crystal plane of a given substance is perpendicular to the beam direction. Moreover, since the beam direction is a plurality of directions perpendicular to the plurality of densest planes of the single crystal thin film to be formed, the single crystal thin film is formed. Furthermore, since the temperature at which the gas beam is irradiated is maintained at the Debye temperature of the predetermined substance or higher, the single crystallization of the predetermined substance efficiently proceeds.

<Operation of the method of the fourteenth invention> In the method of the fourteenth invention, since the gas to be irradiated is an inert gas, even if atoms or ions of the gas remain in the thin film after irradiation, These rarely adversely affect the electronic properties of the thin film as impurities.

<Operation of the method of the fifteenth invention> In the method of the fifteenth invention, the atomic weight of the element constituting the irradiated inert gas is higher than the maximum atomic weight of the constituent elements of the predetermined substance to be irradiated. Therefore, most of the irradiated atoms or ions of the inert gas recoil backward at the surface of the thin film or in the vicinity thereof, and are hard to remain in the thin film.

<Operation of the method of the sixteenth invention> In the method of the sixteenth invention, the atomic weight of the element constituting the irradiated inert gas is the value closest to the maximum atomic weight of the element constituting the predetermined substance. Therefore, the irradiation effect of the beam can be maximized.

<Operation of the method of the seventeenth invention> In the method of the seventeenth invention, since the gas to be irradiated contains a constituent element of a predetermined substance to be irradiated, after the irradiation, atoms of this constituent element or Even if the ions remain in the thin film, there is no fear that these will act as impurities and adversely affect the electrical properties or optical properties of the thin film.

<Operation of the method of the eighteenth invention> In the method of the eighteenth invention, the reaction gas contains a gaseous substance containing an impurity element to be added to a predetermined substance, so that a thin film doped with a desired impurity is obtained. Is formed.

<Operation of the method of the nineteenth invention> In the method of the nineteenth invention, a multilayer film is formed at a constant temperature, for example, by keeping the substrate temperature constant. Therefore, residual stress in the multilayer thin film is reduced.

<Operation of the method of the twentieth or twenty-first invention> In the method of the twentieth or twenty-first invention, since the reflector for converging the gas beam onto the substrate is arranged around the substrate, the gas The substrate is efficiently irradiated with the beam.

<Operation of the method of the twenty-second invention> In the method of the twenty-second invention, at least the surface of the reflection plate which is irradiated with the gas beam is made of a material which does not cause sputtering by the gas beam. Therefore, the elements forming the reflector are not attached to the surface of the substrate by sputtering and adversely affect the electrical and optical characteristics of the formed thin film. Further, there is no fear that the reflection plate will be worn out by sputtering.

<Operation of the method of the twenty-third invention> In the method of the twenty-third invention, at least the surface of the reflecting plate which is irradiated with the beam of gas is composed of the element constituting the substance on the uppermost surface of the substrate. Therefore, even if the element forming the reflection plate adheres to the substrate surface by sputtering, it does not adversely affect the electrical and optical characteristics of the formed thin film.

<Operation of the method of the twenty-fourth invention> In the method of the twenty-fourth invention, when forming a multilayer film, a low energy gas beam is used so that all layers do not cause sputtering. Therefore, it is possible to prevent the substance of the underlayer already formed from being sputtered and mixed into the upper layer being formed. Further, when performing this method using the film forming apparatus, the constituent elements of each layer of the multilayer film deposited in the chamber of the film forming apparatus are sputtered,
It can also be prevented from being mixed into the thin film being formed.

<Operation of the method of the twenty-fifth invention> In the method of the twenty-fifth invention, since the beam of gas is irradiated before depositing the predetermined substance, the substrate or the underlayer is preliminarily cleaned. That is, contaminants adhering to the surface of the substrate or the underlying layer are removed.

<Operation of the method of the twenty-sixth invention> In the method of the twenty-sixth invention, in the plasma irradiation apparatus, the gas beam generation source uses microwaves to generate plasma and the plasma is guided to the substrate by a divergent magnetic field. Therefore, it is possible to easily obtain ions or neutral atoms or molecules having a required energy of several tens of electron volts as a gas beam.

<Operation of the method of the twenty-seventh invention> In the method of the twenty-seventh invention, the collision energy is desired when the beam impinging on the substrate contains ions by setting the potential of the substrate to a desired value. Can be controlled to the size of. For this reason, the energy of the ion beam can be reliably lowered below the sputter threshold (threshold energy in sputtering).

<Operation of the method of the twenty-eighth invention> In the method of the twenty-eighth invention, since the electron blocking member is used, generation of the plasma sheath on the substrate can be suppressed. Therefore, even if the substrate or the thin film formed on the substrate is made of an insulating material, charge accumulation on the substrate is suppressed. As a result, even when the beam impinging on the substrate contains ions, the energy of the ion beam can be surely lowered below the sputtering threshold.

<Operation of the methods of the twenty-ninth to thirty-first inventions>
In the method of any of the twenty-ninth to thirty-first inventions, since the temperature at which the beam of gas is irradiated while depositing the predetermined substance is maintained at the Debye temperature of the predetermined substance or higher, the rearrangement of atoms is performed. Will proceed smoothly.

<Operation of the methods of the thirty-second to thirty-fourth inventions>
In the method according to any one of the thirty-second to thirty-fourth inventions, the temperature is maintained at 400 ° C. or higher when the crystalline thin film of silicon is formed using silane gas. Therefore, hydrogen gas that remains in the silicon and hinders crystallization in the process of depositing silicon on the substrate by the silane gas is removed to the outside by the action of heat of 400 ° C. or more.

[0072]

【Example】

<1. First Embodiment> First, a first embodiment of the present invention will be described.

<1-1. Structure of Apparatus> FIG. 1 is a sectional view of a thin film forming apparatus capable of effectively implementing the method for forming a polycrystalline thin film or an axially oriented polycrystalline thin film of the present invention. As shown in FIG. 1, the present apparatus 102 includes a reaction container 1 and an electron cyclotron resonance (ECR) ion generator 2.
In FIG. 1, 3 is a plasma container, 4 is a plasma chamber,
A magnetic coil 5 for applying a DC magnetic field is installed on the outer periphery of the plasma container 3. Above the plasma container 3, a waveguide 6 for introducing microwaves into the plasma chamber 4 and a gas introduction pipe 7 for introducing an inert gas such as Ne into the plasma chamber 4 are installed.

The inside of the reaction vessel 1 is a reaction chamber 8. An outlet 9 for introducing plasma into the reaction chamber 8 is opened at the center of the bottom of the plasma container 3. A sample stage 10 is installed in the reaction chamber 8 directly below the outlet 9, and a substrate 1 for forming a thin film on the sample stage 10.
1 is installed. In addition, a reaction gas for forming a thin film of a predetermined substance on the substrate 11 is supplied to the reaction chamber 8 through the reaction gas supply pipe 13. In the example of FIG. 1, three reaction gas supply pipes 13a, 13b, 13c are provided. The reaction chamber 8 is further evacuated via a vacuum exhaust pipe 14.
The gas is evacuated and is maintained at a predetermined degree of vacuum by a vacuum evacuation device (not shown) linked with the vacuum gauge 15.

<1-2. Operation of ECR Ion Generator 2> Next, the operation of the ECR ion generator 2 will be described. In order to operate the device 102, gas is introduced into the plasma chamber 4 from the gas introduction pipe 7, and at the same time, microwaves are introduced into the plasma chamber 4 from the waveguide 6. Further, at the same time, a direct current is applied to the magnetic coil 5 so that the plasma chamber 4
And a DC magnetic field is formed around it. In the plasma chamber 4, a phenomenon called cyclotron resonance is caused by the microwave and the DC magnetic field. By this phenomenon, high-energy electrons that make a spiral motion are generated, and the supplied gas is turned into plasma by the electrons.

Since this electron has a diamagnetic property,
An electron flow is formed along the weak magnetic field, that is, along the lines of magnetic force. Since the magnetic coil 5 generates a divergent magnetic field in the reaction chamber 8, an electron flow that spreads downward along the magnetic field lines diverging from the outlet 9 is formed. Then, in order to maintain the electrical neutrality, the positive ions also form an ion flow along the lines of magnetic force along with the electron flow. Since the ion flow and the electron flow flow while recombining with each other, they gradually change into a neutral atomic flow. As described above, by using the ECR ion generator 2, it is possible to relatively easily obtain an ion flow or a neutral atom flow that falls on the substrate 11 in a state close to a parallel flow with uniform traveling directions.

<1-3. Operation of Device 102> Next, Device 1
02, a method for forming a polycrystalline thin film or an axially oriented polycrystalline thin film will be described. As the substrate 11, for example, a glass substrate such as Corning # 7059 is used,
On this glass substrate, a polycrystalline silicon thin film, or
Take an example of forming an axially oriented polycrystalline silicon thin film.
First, a gas such as SiH ₄ (silane) or Si ₂ H ₆ (disilane) for supplying Si is supplied from the reaction gas supply pipe 13a. Here, when the silicon thin film to be formed is p-type, B ₂ H ₆ (diborane) gas for doping p-type impurities is used, and when it is n-type, n-type impurities are doped. PH ₃ (phosphine) gas, AsH ₃ (arsine) gas, or the like may be supplied from the reaction gas supply pipes 13b and 13c.

When the inert gas is introduced through the gas introduction pipe 7, it is desirable to introduce Ne, He or the like having a smaller atomic weight than Si. Here, in order to form the polycrystalline silicon or the axially oriented polycrystalline silicon thin film more effectively, it is preferable to use Ne having a relatively large atomic weight.
In the following description, the case where Ne is used as the inert gas will be described.

When the above-described gas is introduced and the apparatus shown in FIG. 1 is operated, the Ne ion flow and the electron flow formed in the ECR ion generator 2 as described above are discharged from the extraction port 9 to the substrate 11 Flowing in the direction of. The plasma flow of the reaction gas such as SiH ₄ and Si ₂ H ₆ supplied from the reaction gas supply pipe 13 proceeds by the flow of Ne ions or the flow of neutral atoms and electrons, and the glass substrate 11 A Si thin film grows on the upper surface. At this time, the substrate 11 is kept at a low temperature (for example, the substrate is not heated) where the crystallization of Si does not occur in the ordinary plasma CVD. Therefore, the Si thin film is first formed on the substrate 11 as an amorphous Si film which is amorphous. Here, the amount of Ne ions or neutral atoms in the reaction chamber 8 is set to Si.
The amount of gas introduced is adjusted so that the amount of reaction gas such as H ₄ , Si ₂ H ₆ or the like is relatively large so that Ne ions or neutral atoms are irradiated to the substrate 11. Leave.

Here, regarding the plasma energy formed by the ECR ion generator 2, the energy of Ne ions or neutral atoms with which the substrate 11 is irradiated does not cause sputtering of Si, that is, S of Ne.
It is set to a value lower than the threshold energy value of sputtering (about 27 eV) for i. When the amorphous silicon thin film is irradiated with Ne ions or neutral atoms having such an energy value, the silicon atoms of amorphous silicon are rearranged by the energy of Ne. At this time, silicon atoms are rearranged into a more stable polycrystal. As described above, in the present embodiment, the amorphous Si film is subjected to plasma CV.
By irradiating the Si thin film grown on the substrate 11 with Ne ions or neutral atoms while growing in D, the Si atoms are rearranged, and the polycrystalline silicon thin film has a crystallization temperature (about 600 ° C.). It can be formed as follows.

Under the same formation conditions as the above-described formation of polycrystalline silicon, Ne ions or neutral atoms are
By adjusting the pressure in the reaction chamber 8 and the distance from the plasma outlet 9 to the substrate 11 so that the substrate 11 is irradiated in the form of a parallel flow whose directions are relatively uniform, Ne
The main irradiation direction of the ions or neutral atoms to the substrate 11 can be substantially aligned with the normal direction of the substrate. Under such conditions, the plane perpendicular to the irradiation direction of Ne is the (111) plane which is the densest plane of silicon. By doing so, an axially oriented polycrystalline silicon film can be formed in which the crystal axes of the polycrystalline silicon thin film are oriented in the substrate normal direction.

Further, by supplying B ₂ H ₆ gas, PH ₃ gas, AsH ₃ gas or the like at a specified amount at the same time from the reaction gas supply pipe 13, the plasma CVD reaction by these reaction gases also progresses at the same time. , B (boron), P
It is possible to form a p-type or n-type polycrystalline silicon thin film or an axially oriented polycrystalline silicon thin film in which (phosphorus) or As (arsenic) is added at a desired concentration. In addition, supply of a reaction gas containing these impurity elements,
By controlling the silicon thin film during formation, for example, an n-type silicon layer or an intrinsic silicon layer is formed on the p-type silicon layer to form a multilayer film of silicon of different types. Can be easily formed.

In the above example, Ne was used as the plasma flow. The reason for this is as follows:
This is because the atomic weight is larger than that of the e atom, so that when the ions or atoms of Ne collide with the Si thin film, there is a high probability of being scattered backward, and it is difficult for the ions or atoms of Ne to enter and remain in the Si thin film. Secondly, since Ne is an inert gas, it does not form a compound with either Si or the doped impurities even if it penetrates into and remains in the Si thin film.
It can be said that the influence on the electrical or optical characteristics of the Si thin film is small. Moreover, the formed Si thin film can be easily removed to the outside by keeping it at a high temperature to some extent. This also applies to He, but since Ne has a closer atomic weight to Si than He, crystallization becomes possible more effectively than He.

<1-4. Modification of First Embodiment> First Embodiment
A modified example of the embodiment will be described.

<1-4-1. First Modified Example> In the apparatus of the first embodiment, when a simple polycrystalline thin film (a polycrystalline thin film which is not an axially oriented polycrystalline film) is formed, as shown in FIG. By installing the plate 20, Ne ions or neutral atoms can be efficiently supplied to the substrate 11
Can be irradiated. As a result, the irradiation amount of Ne ions or neutral atoms is substantially increased, the flow rate of the reaction gas can be increased, the film formation rate can be increased, and as a result, the cost can be reduced.

At least the surface of the reflection plate 20 to be irradiated is made of, for example, a material having a threshold energy of sputtering with respect to Ne atoms equal to or higher than that of Si atoms in the example of forming a silicon thin film described in the first embodiment. It is desirable to be formed by.

Table 1 shows the values of the sputtering threshold energy in various combinations of the types of atoms or ions to be irradiated and the elements constituting the target thin film. The values listed in Table 1 are all obtained based on simulations, except for some values that are particularly shown.

[0088]

[Table 1]

From Table 1, it can be seen that, for example, when forming a Si thin film, a material such as aluminum (Al), tungsten (W), or platinum (Pt) may be used. The reflector may be made of Si, which is the same material as the thin film to be formed. In this case, even if sputtering occurs, the sputtered element does not contaminate the thin film.

Furthermore, the shape of the reflecting surface 17 of the reflecting plate 20 may simply be a flat surface set at a certain angle with respect to the surface of the substrate, but preferably, it is most efficient from the direction of the plasma flow 16 and The curved surface is formed so that the substrate 11 is uniformly irradiated with plasma. The plasma flow 16 is E
Since it flows along the magnetic force lines of the CR device, the shape of the curved surface can be obtained by calculation from the distribution of the magnetic force lines.

<1-4-2. Second Modification> In the first embodiment, in order to form a polycrystalline silicon thin film or an axially oriented polycrystalline silicon thin film, a silicon thin film is deposited on the substrate 11 by supplying a reaction gas, In the process, a method of crystallizing this silicon thin film by irradiating with a Ne beam was described. On the other hand, it is also possible to crystallize the amorphous silicon thin film previously formed on the substrate 11 into a polycrystalline silicon thin film or an axially oriented polycrystalline silicon thin film by performing beam irradiation thereafter. In addition, a polycrystalline silicon thin film previously formed on the substrate 11 is
After that, it is also possible to crystallize into an axially oriented polycrystalline silicon thin film.

In order to carry out these methods, the device 1
02 by irradiating the substrate 11 with an inert gas such as Ne without supplying any gas from the reaction gas supply pipe 13 in FIG. 1 as in the first embodiment. . An amorphous silicon thin film or the like is previously formed on the substrate 11 by using another CVD device or the like.

In order to rearrange Si atoms in the already formed amorphous silicon thin film or polycrystalline silicon thin film, as compared with the case of rearranging Si atoms in parallel with the growth of the film of the first embodiment, It requires a lot of energy. Especially when rearranging the polycrystalline silicon thin film,
Need more energy. For this reason, preferably, the temperature of the substrate 11 is kept relatively higher than the Debye temperature of silicon, and the irradiation of the inert gas such as Ne is performed. In order to heat the substrate 11, for example, a heater may be built in the sample table 10.

<1-4-3. Third Modification> In the first embodiment, the case where the beam of the inert gas such as Ne is irradiated to the substrate 11 substantially vertically is described. Therefore, the (111) crystal of the axially oriented polycrystalline silicon thin film to be formed is described. The surface coincides with the substrate normal direction. However, with respect to the substrate 11,
By changing the irradiation angle of the beam of an inert gas such as Ne, it is possible to form the (111) crystal plane of silicon at an arbitrary angle with respect to the substrate normal direction. For that purpose, for example, the sample stage 10 on which the substrate 11 can be installed while being inclined with respect to the beam incident direction may be used.

<1-4-4. Fourth Modification> In the first embodiment, the case where an inert gas such as Ne is used as the gas introduced into the plasma chamber 4 has been described. However, instead of these inert gases, a reaction gas (SiH in the case of SiH ₄ ,
It is also possible to use a gas containing as constituent elements the main constituent elements of the thin film to be formed such as Si ₂ H ₆ . In this case, from the reaction gas supply pipe 13 of FIG. 1, SiH _4, Si ₂ H
_It is not necessary to supply gas such as ₆ .

Even in this case, for example, since SiH ₄ functions as a reaction gas, SiH ₄ molecules,
Alternatively, decomposed radicals or the like are applied to the substrate 11. As a result, rearrangement of Si atoms occurs, so that a polycrystalline silicon thin film or an axially oriented polycrystalline silicon thin film is formed as in the first embodiment.

<1-4-5. Fifth Modification> Preferably, in the apparatus 102, the sample stage 10 can be rotated during thin film formation. By doing so, it becomes possible to form a uniform thin film in terms of film quality and film thickness.

<1-4-6. Sixth Modification> In the first embodiment, the method of forming polycrystalline silicon or an axially oriented polycrystalline silicon thin film has been described. However, using the apparatus shown in FIG. It is also possible to form a crystalline thin film or an axially oriented polycrystalline thin film.
As an example, Table 2 shows a gas material for a beam, a reactive gas material, and an impurity gas material to be introduced when forming a thin film of a semiconductor-related material containing silicon.

[0099]

[Table 2]

Further, in various combinations of the type of the atom or ion to be irradiated and the element constituting the target thin film, the ion or atom having an energy lower than the value of the threshold energy of sputtering shown in Table 1 is used. By irradiating with, it is possible to form various polycrystalline thin films or axially oriented polycrystalline thin films. In addition,
The thin film made of a compound may be irradiated with ions or atoms having an energy lower than the threshold energy value of the element having the largest atomic weight among the constituent elements.

<Second Embodiment> In the first embodiment, polycrystal,
Alternatively, the method for forming the axially oriented polycrystalline thin film has been described, but it is also possible to form a single crystal thin film by beam irradiation. In this case, the beam may be irradiated onto the substrate 11 from a plurality of directions perpendicular to the plurality of densest planes of the desired single crystal thin film to be formed. For this purpose, for example, the device 100 shown in FIG. 1 may be used. This device 100 is characteristically different from the device 102 in that the reflecting plate 12 is installed on the sample stage 10 so as to be located above the substrate 11.
Other structural features are similar to device 102.

FIG. 4 is a perspective view of an example of the reflector 12. The reflector 12a is an example of a reflector for forming a single crystal having a diamond structure, such as single crystal Si. The reflector 12a defines an opening at the center of the flat base 21. Three rectangular parallelepiped blocks 22 are fixedly installed around the opening, and reflection blocks 23 are fixed inside the blocks. As a result, an equilateral triangular opening 24 framed by these reflection blocks 23 is formed in the center of the base 21. In the reflection block 23, the slope 25 facing the opening 24 functions as a reflection surface that reflects the gas beam. Therefore, the inclination angle of the slope 25 is set to 55 ° corresponding to the direction of the crystal axis of the single crystal to be formed.

A part of the Ne ion flow or the neutral atom flow downward from the outlet 9 is reflected by the three slopes 25 formed on the reflection plate 12 a, and further passes through the opening 24 to the substrate 11. Incident on the upper surface of. Also, Ne
The other part of the atomic flow does not enter the slope 25 and the opening 24
And then directly enters the upper surface of the substrate 11. That is, the Si thin film being formed on the upper surface of the substrate 11 is
A four-component Ne atomic flow consisting of a component straight from the outlet 9 and three components reflected by the three slopes 25 is irradiated. Since the inclination angle of the slope 25 is set to 55 °, the incident directions of these four component Ne atomic flows are four independent close-packed crystal faces of the Si single crystal to be formed, that is, the (111) face. It corresponds to four directions perpendicular to.

As a result, since the Si atoms are rearranged so that the planes perpendicular to the incident direction of each of these components are the densest planes, single crystal Si having a single crystal orientation is formed. It That is, the amorphous Si thin film growing by plasma CVD is sequentially converted into a single crystal Si thin film having a uniform crystal orientation.

The same modified example as that of the first embodiment can also be implemented in the second embodiment. For example, after forming an amorphous or polycrystal (including axially oriented polycrystal) Si thin film on the substrate 11 in advance, the apparatus 100 may be used to single crystallize the Si thin film. At this time, it is desirable that the temperature of the substrate 11 be maintained above the Debye temperature of Si.

<3. Third Embodiment> In the first and second embodiments, the method of forming a crystalline thin film has been described.
It is also possible to efficiently form an amorphous thin film by irradiating a beam. In this case,
For example, this can be achieved by irradiating the substrate 11 with a low energy Ne beam that does not recrystallize the amorphous silicon film growing on the substrate 11 by plasma CVD. At this time, the content of hydrogen in the silicon film can be changed by changing the introduction amount of Ne gas with respect to the introduction amount of SiH ₄ which is a reaction gas.
This is because the irradiation of Ne ions or atoms causes the hydrogen atoms taken into the silicon film to be sputtered.

As another method, in the same method as the above-mentioned polycrystalline thin film formation, the amount of Ne introduced is reduced so that the silicon thin film rate is faster than the case where the substrate silicon is sufficiently crystallized. As a result, it is possible to form an amorphous thin film that is an aggregate of ultrafine crystals. As a special example, an amorphous thin film is formed even when Ne is not introduced at all.

<4. Fourth Embodiment> FIG. 5 is a front sectional view of a thin film forming apparatus suitable for carrying out a method for forming a multi-layered thin film in which various types of layers are laminated. In this device 140, a desired gas is selected as a gas to be introduced into the gas introducing pipe 7 from a large number of gas cylinders 31 in which various kinds of gases are stored, by the action of the gas selector 32. Further, as the reaction gas introduced into the reaction gas supply pipe 13, a desired gas is selected by the function of the gas selector 34 from a large number of gas cylinders 33 in which various kinds of gases are stored. In the gas cylinder 33, not only the reaction gas for supplying the main component of the substance forming the thin film, but also the reaction gas containing impurities to be added to the main component is prepared.

Further, the tilting and rotating direction of the sample table 10 can be adjusted by the driving device 35. FIG. 6 is a partially enlarged view showing the movement of the sample table 10. Gas selector 3
The operations of 2, 34 and the drive unit 35 are controlled by the controller 36.

Since the sample table 10 freely tilts and rotates, the irradiation direction of the beam on the substrate 11 can be set arbitrarily. Therefore, when forming the axially oriented polycrystalline thin film or the single crystal thin film, its crystal orientation can be arbitrarily selected. In particular, when forming a single crystal thin film, the beam is irradiated from a plurality of directions perpendicular to a plurality of densest planes of the single crystal thin film to be formed, as shown by a solid line and a wavy line in FIG. 6, for example. The two postures should be taken alternately. By irradiating the beams from a plurality of directions in a time-division manner, single crystallization can be realized as in the case of simultaneously irradiating from a plurality of directions by the method of the second embodiment using the reflector 12.

In this apparatus 140, by controlling the attitude of the sample table 10, it is possible to form thin films having all desired single crystal, polycrystal, axially oriented polycrystal, and amorphous crystal structures. . Moreover, the crystal orientation can be set in any desired direction. Further, by operating the gas selectors 32 and 34, it is possible to form a thin film of any desired substance. It is also possible to form a thin film to which desired impurities are added.

In addition, the substrate 11 is used as the sample table 1 in the reaction chamber 8.
After being installed at 0, the crystal structure is changed by gradually changing the operations of the driving device 35 and the gas selectors 32 and 33.
It is also possible to form a multilayer thin film having a plurality of layers having different crystal orientations, kinds of substances, or added impurity elements.

As one of application examples, oxygen (O ₂ ) is introduced from the gas introduction pipe 7 into the plasma chamber 4 after forming the silicon thin film, and SiH ₄ as a reaction gas
By supplying a gas such as Si ₂ H ₆ , a silicon oxide film (SiO ₂ ) can be continuously formed on the silicon thin film. When the constituent material of the substrate 11 may adversely affect the device formed on the substrate 11, for example, first, a silicon oxide film is formed,
After that, if the silicon crystal thin film and the silicon oxide film are formed again, the first silicon oxide film serves as a separation layer between the substrate and the device formed thereon, and a device having excellent characteristics can be formed. Become.

As described above, by combining various gases introduced into the plasma chamber or reaction gases introduced into the reaction chamber, various kinds of films having excellent crystallinity can be maintained at a low temperature and a high degree of vacuum can be maintained. Since it can be continuously formed on the substrate as it is, moisture and the like are not adsorbed on the interface of the film, and excellent interface characteristics can be realized.

When a new layer is formed on the substrate 11 or the underlayer, the substrate 11 or the underlayer may be irradiated with a beam in advance to clean the surface. By doing so, the adhesion between the newly formed layer and the substrate or the base layer is improved.

<5. Fifth Embodiment> Here, an experiment demonstrating that a polycrystalline silicon thin film and an axially oriented polycrystalline silicon thin film are formed by the method of the first embodiment will be described.

In this demonstration experiment, the device 102 shown in FIG.
Based on the conditions shown in Table 3, using a device equivalent to
A silicon thin film was formed on an amorphous glass substrate.

[0118]

[Table 3]

FIG. 7 is a reflection electron beam diffraction image of the formed silicon thin film. FIG. 7A is a backscattered electron beam diffraction image of the silicon thin film formed under the condition 1 among the conditions shown in Table 3, and FIG. 7B is a backscattered electron beam diffraction image of the silicon thin film formed under the condition 2. It is an analysis image.

In FIG. 7A, diffraction spot points (see FIG.
(Center of (a)) is observed, and concentric light and dark stripes that are light as a whole are observed around it. This shows the characteristics of the axially oriented polycrystalline silicon film in which the (111) crystal planes of silicon are aligned in the direction of the substrate normal. On the other hand, in FIG. 7B, clear diffraction spots are observed in a concentric pattern. This shows the characteristics of a typical polycrystalline silicon film. That is, it was found that the condition 1 forms an axially oriented polycrystalline silicon thin film, and the condition 2 forms a polycrystalline silicon thin film (not an axially oriented polycrystalline film).

In the apparatus 102, Ne ions or neutral atoms collide with the Si thin film to cause rearrangement of Si crystals, thereby promoting crystallization. Therefore, first, unless the introduction flow rate ratio of the inert gas Ne to the reaction gas SiH ₄ is more than a certain level (in this experiment, the SiH ₄ gas is 1 to the Ne gas 5 or more), the growth rate of the silicon film is high. On the other hand, since Ne ions or neutral atoms are not sufficiently irradiated to the substrate 11, the formed thin film is an amorphous silicon thin film. In this experiment, by introducing Ne gas of Ne gas 5 or more to SiH ₄ gas 1, a normal plasma CV of 300 ° C. or less was obtained.
It was confirmed that in D, a polycrystalline silicon thin film was obtained at a low temperature at which crystallization did not occur.

Further, in the apparatus 102, crystals are formed so that the densest plane becomes perpendicular to the direction in which the Ne ions or neutral atoms are irradiated on the substrate 11, and therefore, the same process as the polycrystalline silicon thin film formation is performed. Under the film conditions, it is possible to achieve the formation of an axially oriented polycrystalline thin film by aligning the main irradiation directions of Ne ions or neutral atoms. As shown in the experimental conditions in Table 3, in this experiment, the operating pressure was 1 × 10 ⁻³ To.
It can be seen that rr is the boundary between the polycrystal and the axially oriented polycrystal. This means that when the operating pressure is lowered and the Ne ions or neutral atoms are irradiated to the substrate within the mean free path of Ne, in other words, a large number of Ne ions or neutral atoms are not transferred to the other. It is shown that when the ions reach the substrate without colliding with the gas, the irradiation directions of Ne ions or neutral atoms with respect to the substrate are aligned, whereby an axially oriented polycrystalline silicon thin film is formed.

In the above proof experiment, the polycrystalline silicon thin film or the axially oriented polycrystalline silicon thin film was tested at 300 ° C.
It was confirmed that it can be formed at a low temperature as below. It is possible to form not only silicon but also polycrystalline or axially oriented polycrystalline thin films of other materials.

The film forming conditions for the silicon thin film shown in Table 3 are peculiar to the device 102, but the following principles are applicable to any device such as polycrystalline silicon thin film or axially oriented polycrystal. It is applied to thin film formation. That is, in order to crystallize silicon at a low temperature, no matter what device is used, the growth rate of a silicon film per unit time is compared with that of Ne ions or neutral atoms irradiated per unit area. The amount must exceed a certain value. Moreover, in order to achieve axial orientation,
It is necessary to align the main irradiation directions of Ne ions or neutral atoms to the substrate while satisfying the crystallization conditions.

Further, the higher the substrate temperature during film formation, the easier the crystallization. Therefore, it is better to form a film at a temperature as high as possible.
The film forming speed can be increased, which is advantageous in practical use. In addition, the case of forming a polycrystalline thin film, by using the reflection plate shown in FIG. 2, it is possible to increase the dose of substantial Ne ions or neutral atoms into the substrate, such as SiH ₄ gas Crystallization is possible even if the flow rate is increased, and as a result, the film formation rate can be increased, which is further advantageous in practical use.

<6. Sixth Embodiment> Next, an experiment demonstrating that a single crystal silicon thin film is formed by the method of the second embodiment will be described.

In this demonstration experiment, the apparatus 100 shown in FIG.
Was used to form a silicon thin film on an amorphous glass substrate under the condition 1 shown in Table 3. FIG.
[Fig. 4] is a backscattered electron diffraction image of the formed silicon thin film. As shown in FIG. 8, many diffraction spot points arranged in a lattice are observed. This indicates that the formed thin film is a single crystal silicon thin film. That is,
It was found that a single crystal silicon thin film was formed under the condition 1.

<7. Seventh Embodiment> When performing the method of the first embodiment, the device 10 shown in FIG.
It is more desirable to use 3. In this device 103, a seed remover (electron blocking member) 1 is mounted on the sample table 10.
The device 8 is characteristically different from the device 102 in that 8 is installed above the substrate 11. Sea remover 1
8 is fixed on the sample table 10 via, for example, a support column 19, and has a function of suppressing generation of a plasma sheath on the substrate 11.

FIG. 10 is a perspective view showing an example of the structure of the sheath remover 18. The sheath remover 18a is a flat plate made of a conductive material such as metal and having a circular opening in the center. The sheath remover 18a is placed in the plasma so that the opening surface of the opening is perpendicular to the magnetic field lines B _ECR . The thickness of the sheath remover 18a, that is, the depth T _{S of} the opening and the diameter D _{S of the} opening are set according to the amount of energy of the electrons to be removed. Further, preferably, the sheath remover 18a is electrically grounded.

[0130] Since the sheath remover 18a is configured like this, among the electrons that move along the magnetic field lines B _ECR of the divergent magnetic field while spiraling around the magnetic field lines B _ECR, at a position where the sheath remover 18a is installed , The Larmor diameter D _L is larger than the opening diameter D _S , and the Debye length L _D is shorter than the opening depth T _S , the electrons cannot pass through the opening and the main surface of the sheath remover 18a or the opening Be sure to hit the inner wall. Further, since the sheath remover 18a is grounded, the colliding electrons are promptly removed to the ground potential and are not accumulated or scattered.

That is, electrons having an energy higher than a certain height determined by the opening diameter D _S and the opening depth T _S are captured by the see-slip remover 18a and cannot pass through the see-slip remover 18a. Therefore, as viewed from the ECR ion source 2, electrons having a high energy of a certain level or higher are removed behind the see-through remover 18a, that is, downstream of the see-through remover 18a in the beam of Ne gas.

It is mainly the electrons with high energy in the electrons generated in the plasma chamber 4 that contribute to the generation of the plasma sheath, and the electrons with little energy loss due to collision, that is, high energy is maintained. It is an electron. Therefore, by appropriately setting the opening diameter D _S and the opening depth T _S , it is possible to prevent passage of electrons that contribute to the generation of the plasma sheath. By doing so, it is possible to substantially eliminate the generation of the plasma sheath on the surface of the object such as the substrate 11 placed downstream of the sheath remover 18a.

The device 103 includes a substrate 11 and a reflector 1.
Since the seed remover 18 is placed upstream of the board 2, the board 1
The generation of the plasma sheath on the surface of No. 1 is suppressed.
Therefore, the Ne ion flow in the Ne beam hardly undergoes excessive acceleration that exceeds the sputter threshold, so that the Ne ⁺ ion flow as well as the Ne atomic flow is similar to the Ne atomic flow. Effectively contributes to the formation of a crystalline thin film. Therefore, the crystalline thin film is formed more efficiently. Further, the substrate 11 or the formed thin film is N
There is no risk of etching due to re-sputtering due to the ions of e. This also contributes to the formation of a highly efficient crystalline thin film.

Also in the method of the second or fourth embodiment, the sheath remover 18 can be similarly used, and the same effect can be obtained.

<8. Eighth Embodiment> In the first, second, or fourth embodiment, the temperature of the substrate 11 is being deposited when the beam is irradiated while supplying the reaction gas to form the crystalline thin film. It is desirable to keep above the Debye temperature of (eg silicon). By doing so, the rearrangement of the atoms that make up the material being deposited proceeds smoothly. Therefore, crystallization of this material (polycrystallization,
Axial orientation polycrystallization and single crystallization) are efficiently performed. Further, the partial pressure of the reaction gas can be set to be relatively higher than that of the gas beam. For this reason, the deposition rate of the predetermined substance is improved, so that the crystalline thin film is rapidly formed.

<9. Ninth Embodiment> In the first, second, or fourth embodiment, in order to form a crystalline silicon thin film, a silane gas is used as a main component of the reaction gas, and a beam is formed while supplying the reaction gas. It is desirable to maintain the temperature of the substrate 11 at 400 ° C. or higher during irradiation. By doing so, hydrogen gas that remains in the silicon and hinders crystallization during the process of depositing the silicon on the substrate is removed to the outside by the action of heat of 400 ° C. or higher. Therefore, crystallization of silicon is promoted,
Crystallinity improves with the film formation rate. As a result of the improved crystallinity, the electrical characteristics of the formed silicon film are also improved.

[0137]

【The invention's effect】

<Effect of the first invention> In the method of the first invention, by depositing a predetermined substance on the substrate and irradiating the substrate with a beam of gas therein, the predetermined substance does not crystallize. At a temperature, generally, a polycrystalline thin film having better electrical and optical characteristics than an amorphous thin film can be obtained. Further, since the thin film is formed at a low temperature, a relatively inexpensive material having low heat resistance can be used as the substrate material, and the manufacturing cost can be reduced. In addition, since the thin film is formed at a low temperature, contamination during film formation is unlikely to occur.

<Effect of the Second Invention> In the method of the second invention, an amorphous thin film of a predetermined substance is formed in advance on a substrate, and then the substrate is irradiated with a gas beam. At a low temperature at which a given substance does not crystallize, a polycrystalline thin film generally superior in electrical and optical properties to an amorphous thin film can be obtained. Further, since the thin film is formed at a low temperature, a relatively inexpensive material having low heat resistance can be used as the substrate material, and the manufacturing cost can be reduced. In addition, since the thin film is formed at a low temperature, contamination during film formation is unlikely to occur.

<Effect of the Third Invention> In the method of the third invention, a predetermined substance is crystallized by irradiating the substrate with a gas beam while depositing a predetermined substance on the substrate. At a low temperature that does not change, an axially oriented polycrystalline thin film, which generally has better electrical and optical characteristics than an amorphous thin film or a polycrystalline thin film, can be obtained. Further, since the thin film is formed at a low temperature, a relatively inexpensive material having low heat resistance can be used as the substrate material, and the manufacturing cost can be reduced. In addition, since the thin film is formed at a low temperature, contamination during film formation is unlikely to occur.

<Effect of Fourth Invention> In the method of the fourth invention, an amorphous thin film or a polycrystalline thin film of a predetermined substance is formed on the substrate in advance, and then the substrate is irradiated with a gas beam. By doing so, it is possible to obtain an axially oriented polycrystalline thin film that is generally superior in electrical and optical characteristics to an amorphous thin film or a polycrystalline thin film at a low temperature at which a predetermined substance does not crystallize. Further, since the thin film is formed at a low temperature, a relatively inexpensive material having low heat resistance can be used as the substrate material, and the manufacturing cost can be reduced. In addition, since the thin film is formed at a low temperature, contamination during film formation is unlikely to occur.

<Effect of Fifth Invention> In the method of the fifth invention, in the process of depositing a predetermined substance at a low temperature at which crystallization does not occur, rearrangement of atoms constituting the predetermined substance is performed. The substrate is irradiated with a low energy gas beam that does not occur. Therefore, crystallization is not promoted by the gas beam, and hydrogen atoms taken in as impurities in the predetermined substance that is being deposited are removed by sputtering with the gas beam. As a result, the predetermined substance is efficiently formed as an amorphous thin film.

<Effect of Sixth Invention> According to the method of the sixth invention, a thin film having a plurality of layers having different crystal structures is formed at a relatively low temperature. For example, when the solar battery cell is made of silicon, the power generation layer is preferably amorphous or microcrystal that behaves like a direct transition type, and the electrode layer has a low defect density and carrier mobility, Alternatively, a single crystal having a long carrier life is suitable. Therefore, if a structure in which an amorphous or microcrystalline layer is sandwiched by single crystal layers can be realized, a solar battery cell with excellent power generation efficiency can be constructed. Moreover, by using the method of the present invention, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained.

<Effect of Seventh Invention> In the method of the seventh invention, a thin film having a plurality of single crystal layers having different crystal orientations or a plurality of axially oriented polycrystal layers by changing the direction of the gas beam. Is formed. Moreover, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained.

<Effect of Eighth Invention> In the method of the eighth invention, a thin film having a plurality of layers of different substances is formed by changing the kinds of reaction gases. Moreover, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained.

<Effect of Ninth Invention> In the method of the ninth invention, a thin film having a plurality of layers of an insulator, a semiconductor, or a conductor is formed by appropriately selecting a reaction gas. Therefore, for example, a TFT transistor (thin film transistor) including a silicon single crystal, an insulating film such as a silicon oxide film or a silicon nitride film, and a gate electrode film of polycrystalline or polycrystalline silicon can be formed.

Moreover, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained. Therefore, for example, it is possible to realize a TFT transistor in which characteristics such as threshold voltage or current driving force are uniform and stable.

<Effect of Tenth Invention> In the method of the tenth invention, the type of the impurity element added to the reaction gas is made different to form a thin film having a plurality of layers with different added impurities. Moreover, since such a multilayer film can be continuously formed in a vacuum, contaminants such as moisture do not adhere to the interface, so that excellent interface characteristics can be obtained.

<Effect of the Eleventh Invention> In the method of the eleventh invention, in forming the amorphous layer, in the process of depositing a predetermined substance at a low temperature at which crystallization does not occur, A substrate is irradiated with a beam of gas having low energy to such an extent that rearrangement of atoms constituting a predetermined substance does not occur. Therefore, crystallization is not promoted by the gas beam, and hydrogen atoms taken in as impurities in the predetermined substance that is being deposited are removed by sputtering with the gas beam. As a result, the predetermined substance is efficiently formed as an amorphous thin film.

<Effect of the twelfth invention> In the method of the twelfth invention, since the temperature at the time of irradiating the beam of gas is kept at the Debye temperature of the predetermined substance or higher, the predetermined substance is polycrystallized, Alternatively, the axial orientation polycrystallization progresses efficiently.

<Effect of Thirteenth Invention> In the method of the thirteenth invention, an amorphous thin film or the like of a predetermined substance is formed on the substrate in advance, and then the substrate is irradiated with a gas beam. At a low temperature at which a predetermined substance does not crystallize, a single crystal thin film that is generally superior in electrical and optical characteristics to any of an amorphous thin film, a polycrystalline thin film, and an axially oriented polycrystalline thin film can be obtained. Further, since the thin film is formed at a low temperature, a relatively inexpensive material having low heat resistance can be used as the substrate material, and the manufacturing cost can be reduced. Since the thin film is formed at a low temperature, contamination during film formation is unlikely to occur. Furthermore, since the temperature at which the gas beam is irradiated is maintained at the Debye temperature of the predetermined substance or higher, the single crystallization of the predetermined substance efficiently proceeds.

<Effect of Fourteenth Invention> In the method of the fourteenth invention, since the gas to be irradiated is an inert gas, even if atoms or ions of the gas remain in the thin film after the irradiation, these are It has an effect of not adversely affecting the electronic properties of the thin film as an impurity.

<Effect of Fifteenth Invention> In the method of the fifteenth invention, the atomic weight of the element constituting the irradiated inert gas is lower than the maximum atomic weight of the constituent element of the predetermined substance to be irradiated. Therefore, most of the irradiated atoms or ions of the inert gas recoil backward on the surface of the thin film or in the vicinity thereof, and are hard to remain in the thin film.

<Effect of Sixteenth Invention> In the method of the sixteenth invention, the atomic weight of the element constituting the irradiated inert gas is the value closest to the maximum atomic weight of the element constituting the predetermined substance. Therefore, the irradiation effect of the beam can be maximized. Therefore, the amount of the inert gas introduced can be suppressed to be smaller than the amount of the reaction gas introduced.
Alternatively, the rate of forming a thin film having a predetermined crystal structure is improved.

<Effect of Seventeenth Invention> In the method of the seventeenth invention, since the gas to be irradiated contains a constituent element of a predetermined substance to be irradiated, the atom or ion of this constituent element is changed after the irradiation. Even if they remain in the thin film, there is no fear that these will adversely affect the electrical properties or optical properties of the thin film as impurities.

<Effect of the 18th Invention> In the method of the 18th invention, the reaction gas contains a gaseous substance containing an impurity element to be added to a predetermined substance, thereby forming a thin film doped with a desired impurity. To be done.

<Effect of Nineteenth Invention> In the method of the nineteenth invention, a multilayer film is formed at a constant temperature, for example, by keeping the substrate temperature constant. Therefore, residual stress in the multilayer thin film can be reduced, and as a result, a thin film device having excellent electrical or optical characteristics can be obtained.

<Effects of the twentieth and twenty-first inventions> In the method of the twentieth or twenty-first invention, since the reflector for converging the gas beam onto the substrate is arranged around the substrate, the gas beam is efficiently produced. The substrate is well illuminated. Therefore, even if the partial pressure ratio of the reaction gas is increased, crystallization can be performed, and as a result, the film formation rate can be increased and the manufacturing cost can be reduced.

<Effect of the 22nd Invention> In the method of the 22nd invention, at least the surface of the reflection plate which is irradiated with the gas beam is made of a material which does not cause sputtering by the gas beam. Therefore, the elements forming the reflector are not attached to the surface of the substrate by sputtering and adversely affect the electrical and optical characteristics of the formed thin film. Further, there is no fear that the reflection plate will be worn out by sputtering.

<Effect of the twenty-third invention> In the method of the twenty-third invention, at least the surface of the reflecting plate which is irradiated with the beam of gas is composed of the element constituting the substance on the uppermost surface of the substrate, Even if the element forming the reflection plate adheres to the substrate surface by sputtering, it does not adversely affect the electrical and optical characteristics of the formed thin film.

<Effect of 24th Invention> In the method of the 24th invention, when a multilayer film is formed, a low energy gas beam is used so that all layers do not cause sputtering. Therefore, it is possible to prevent the substance of the underlayer already formed from being sputtered and mixed into the upper layer being formed. Further, when the method is performed using the film forming apparatus, it is also possible to prevent the constituent elements of each layer of the multilayer film attached in the chamber of the film forming apparatus from being mixed into the thin film being formed by sputtering. it can. As a result, it is possible to form a multilayer film in which the electrical and optical characteristics of each layer are stable.

<Effect of the 25th Invention> In the method of the 25th invention, since the beam of gas is irradiated before depositing a predetermined substance, the substrate or the underlayer is preliminarily cleaned. That is, contaminants adhering to the surface of the substrate or the underlying layer are removed. As a result, the adhesion between the subsequently formed layer and the substrate or the base layer is improved.
In addition, since the thin film is continuously formed in vacuum after removing the contaminants, the interface with the substrate is kept clean. Therefore, excellent interfacial characteristics are realized in the formed thin film.

<Effect of the twenty-sixth invention> In the method of the twenty-sixth invention, the gas beam generation source is a plasma irradiation apparatus for generating plasma using microwaves and for guiding the plasma to the substrate by a divergent magnetic field. In addition, as the gas beam, ions or neutral atoms or molecules having an energy of several tens of electron volts necessary for the present invention can be easily obtained.

<Effect of the 27th Invention> In the method of the 27th invention, by setting the potential of the substrate to a desired value, the collision energy can be increased to a desired value when the beam impinging on the substrate contains ions. Can be controlled. For this reason, the energy of the ion beam can be reliably lowered below the sputter threshold (threshold energy in sputtering). as a result,
The substrate or the thin film formed is not etched due to ion resputtering.

<Effect of the twenty-eighth invention> In the method of the twenty-eighth invention, since the electron blocking member is used, generation of the plasma sheath on the substrate can be suppressed. Therefore, even if the substrate or the thin film formed on the substrate is made of an insulating material, charge accumulation on the substrate is suppressed. As a result, even when the beam impinging on the substrate contains ions, the energy of the ion beam can be surely lowered below the sputtering threshold. Therefore, the substrate or the formed thin film is not etched due to resputtering by ions.

<Effects of the 29th to 31st inventions>
In the method of any one of the thirty-first inventions, since the temperature at which the beam of gas is irradiated while depositing the predetermined substance is maintained at the Debye temperature of the predetermined substance or higher, the rearrangement of atoms is smooth. Proceed to. Therefore, the crystallization of the predetermined substance is efficiently performed. Further, the partial pressure of the reaction gas can be set to be relatively higher than that of the gas beam. For this reason, the deposition rate of the predetermined substance is improved, so that the crystalline thin film is rapidly formed.

<Effects of 32nd to 34th Inventions> 32nd invention
In the method according to any one of the thirty-fourth inventions, the temperature is set to 40 at the time of forming the crystalline thin film of silicon using silane gas.
Since the temperature is maintained at 0 ° C. or higher, hydrogen gas remaining in the silicon is removed to the outside during the process of depositing the silicon on the substrate by the silane gas. Therefore, crystallization of silicon is promoted, and the crystallinity is improved together with the film formation rate. As a result of the improved crystallinity, the electrical characteristics of the formed silicon film are improved.

[Brief description of drawings]

FIG. 1 is a front sectional view of an apparatus suitable for carrying out the method of the first embodiment.

FIG. 2 is a partially enlarged cross-sectional view of an apparatus further suitable for carrying out the method of the first embodiment.

FIG. 3 is a front sectional view of an apparatus suitable for carrying out the method of the second embodiment.

FIG. 4 is a perspective view of a reflector used in the device of FIG.

FIG. 5 is a front sectional view of an apparatus suitable for carrying out the method of the fourth embodiment.

6 is a partial enlarged cross-sectional view of the device of FIG.

FIG. 7 is a schematic diagram showing the results of the verification experiment of the fifth embodiment.

FIG. 8 is a schematic diagram showing the results of the verification experiment of the sixth embodiment.

FIG. 9 is a front sectional view of an apparatus suitable for carrying out the method of the seventh embodiment.

10 is a perspective view of a sheath remover used in the apparatus of FIG. 9. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reaction container 2 ECR ion generator 6 Waveguide 7 Gas introduction pipe 11 Substrate 13 Reactive gas supply pipe 14 Vacuum exhaust pipe 18 Shear remover (electron blocking member) 20 Reflector plate 12 Reflector plate 35 Driving device 32,34 Gas selector 31 , 33 gas cylinder 36 controller

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Hikawa 15-16 Machikaneyamacho, Toyonaka City, Osaka Prefecture Crystal Device Co., Ltd.

Claims (34)

[Claims] 1. A thin film forming method for forming a polycrystalline thin film of a predetermined substance on a substrate, comprising supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance does not occur. By irradiating the substrate with a beam of gas with low energy to such an extent that the predetermined substance does not cause sputtering in the process of depositing the predetermined substance on the substrate from any of plural directions. And a method for forming a thin film. 2. A thin film forming method for forming a polycrystalline thin film of a predetermined substance on a substrate, wherein an amorphous thin film of the predetermined substance is previously formed on the substrate, and the predetermined substance is used. A thin film characterized by irradiating the amorphous thin film with a beam of a gas having low energy to such an extent that the predetermined substance does not cause sputtering from a plurality of arbitrary directions under a low temperature at which crystallization of the film does not occur. Forming method. 3. A thin film forming method for forming an axially oriented polycrystalline thin film of a predetermined substance on a substrate, wherein a reaction gas is provided on the substrate at a low temperature at which crystallization of the predetermined substance does not occur. In the process of depositing the predetermined substance on the substrate by supplying a low-energy gas beam of such a degree that the predetermined substance does not cause sputtering,
A method for forming a thin film, which comprises irradiating the substrate from one direction. 4. A thin film forming method for forming an axially oriented polycrystalline thin film of a predetermined substance on a substrate, wherein an amorphous thin film or a polycrystalline thin film of the predetermined substance is previously formed on the substrate. Every time, under a low temperature at which crystallization of the predetermined substance does not occur, a beam of gas with low energy such that the predetermined substance does not cause sputtering is unidirectionally applied to the amorphous thin film or the polycrystalline thin film. A method for forming a thin film, which comprises irradiating. 5. A thin film forming method for forming an amorphous thin film of a predetermined substance on a substrate, wherein a reaction gas is formed on the substrate at a low temperature at which crystallization of the predetermined substance does not occur. Irradiating the substrate with a beam of gas having low energy to such an extent that rearrangement of atoms constituting the predetermined substance does not occur in the process of depositing the predetermined substance on the substrate by supplying. And a method for forming a thin film. 6. A thin film forming method for forming a thin film including a plurality of layers having different crystal structures on a substrate, wherein at least two or more of the following steps (a) to (d) are sequentially performed. A thin film forming method, characterized in that
Here, the steps (a) to (d) include: (a) supplying the reaction gas onto the substrate under a low temperature at which crystallization of a predetermined material forming one layer does not occur. In the process of depositing a substance on the substrate, a beam of low energy gas that does not cause the predetermined substance to sputter is irradiated onto the substrate from arbitrary plural directions. Forming a polycrystalline thin film of the substance; (b) supplying the reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur During the process of depositing on the substrate, a beam of low energy gas that does not cause the predetermined substance to sputter is irradiated onto the substrate from one direction, and as a result, the axial alignment of the predetermined substance is increased. Step of forming crystalline thin film; (c) One In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming the layer does not occur, A low energy beam of gas that does not cause sputtering is irradiated onto the substrate from a plurality of directions perpendicular to a plurality of close-packed planes of a single crystal thin film of the predetermined substance to be formed, and as a result, Forming the single crystal thin film of a predetermined substance; and (d) supplying a reaction gas onto the substrate at a low temperature at which crystallization of the single substance of the single layer does not occur. This is a step of forming an amorphous thin film of a predetermined substance. 7. A thin film forming method for forming a thin film comprising a plurality of single crystal layers having different crystal orientations or a plurality of axially oriented polycrystalline layers on a substrate, the method comprising the steps (a) to (d) below: A plurality of steps are sequentially performed by allowing overlapping from the inside, and the steps (a) to (d) are performed at a low temperature at which (a) crystallization of a predetermined substance forming one layer does not occur. In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate, the low energy gas beam that does not cause sputtering of the predetermined substance is applied to the substrate. A step of irradiating upwards from arbitrary plural directions, and as a result, forming a polycrystalline thin film of the predetermined substance; (b) reacting under a low temperature at which crystallization of a predetermined substance forming one layer does not occur. Depositing the predetermined substance on the substrate by supplying a gas onto the substrate In the process, a beam of low energy gas that does not cause sputtering of the predetermined substance is irradiated onto the substrate from one direction, and as a result, an axially oriented polycrystalline thin film of the predetermined substance is formed. (C) In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur. A beam of gas of low energy to such an extent that the predetermined substance does not cause sputtering onto the substrate from a plurality of directions perpendicular to a plurality of close-packed planes of a single crystal thin film of the predetermined substance to be formed. Irradiating, and as a result, forming the single crystal thin film of the predetermined substance; and (d) reacting the reaction gas at a low temperature at a low temperature at which crystallization of the predetermined substance forming one layer does not occur. By feeding on Is a step of forming an amorphous thin film of the predetermined substance, wherein the plurality of steps include at least one of the steps (b) and (c) in an overlapping manner, and between the overlapping steps. A method for forming a thin film, wherein the beam directions are different. 8. A thin film forming method for forming a thin film including a plurality of layers of different substances on a substrate, wherein a plurality of steps are performed while allowing overlap among the following steps (a) to (d). Here, the steps (a) to (d) include the steps of: (a) supplying the reaction gas onto the substrate at a low temperature at which crystallization of a predetermined material forming one layer does not occur. In the process of depositing the substance on the substrate, a beam of gas with low energy that does not cause the predetermined substance to sputter is irradiated onto the substrate from arbitrary plural directions, and as a result, the predetermined amount (B) supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur, During the process of depositing on the substrate, the predetermined substance causes sputtering. A step of irradiating the substrate with a low-energy gas beam that does not rub the substrate in one direction, thereby forming an axially oriented polycrystalline thin film of the predetermined substance; (c) a predetermined one layer The degree to which the predetermined substance does not cause sputtering during the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the substance does not occur. Irradiating a low-energy gas beam onto the substrate from a plurality of directions perpendicular to a plurality of close-packed planes of a single crystal thin film of the predetermined substance to be formed, so that Forming a single crystal thin film; and (d) supplying a reaction gas onto the substrate at a low temperature at which crystallization of one layer of a predetermined substance does not occur, thereby depleting the substance of the predetermined substance. In the process of forming a crystalline thin film Ri, wherein the plurality of steps, a thin film forming method characterized in that the type of the reaction gas comprises two or more different steps. 9. The thin film forming method according to claim 8, wherein in the two or more steps in which the types of the reaction gas are different, the substance deposited by each reaction gas is an insulator,
A method for forming a thin film, characterized in that the type of each reaction gas is selected so that it is either a semiconductor or a conductor. 10. A thin film forming method for forming a thin film including a plurality of layers having different added impurities on a substrate, wherein a plurality of steps are performed while allowing overlap among the following steps (a) to (d). Here, in the steps (a) to (d), (a) by supplying a reaction gas onto the substrate at a low temperature at which crystallization of a predetermined material forming one layer does not occur, In the process of depositing a predetermined substance on the substrate, a beam of low energy gas such that the predetermined substance does not cause sputtering is irradiated onto the substrate from arbitrary plural directions, and as a result, Forming a polycrystalline thin film of a predetermined substance; (b) supplying the reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance forming one layer does not occur. Is deposited on the substrate, the predetermined substance is sputtered. Irradiating the substrate with a low-energy gas beam that does not cause energization from one direction, and as a result forms an axially oriented polycrystalline thin film of the predetermined substance; (c) forming one layer In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a low temperature at which crystallization of the predetermined substance does not occur, the predetermined substance causes sputtering. A low-energy beam of gas having a low level of energy is irradiated onto the substrate from a plurality of directions perpendicular to a plurality of close-packed planes of a single crystal thin film of the predetermined substance to be formed, and as a result, the predetermined substance is irradiated. And (d) by supplying a reaction gas onto the substrate at a low temperature at which crystallization of one layer of a predetermined substance does not occur. Forming an amorphous thin film of A step, said plurality of steps, a thin film forming method characterized in that the impurity element added to the reaction gas contains two or more different steps. 11. The thin film forming method according to claim 6, wherein the step (d) is (c-4-1) at a low temperature at which crystallization of the predetermined substance does not occur. Under the step of depositing the predetermined substance on the substrate by supplying the reaction gas onto the substrate, (c-4-2) in performing the step (c-4-1) A step of irradiating the substrate with a beam of gas having low energy to such an extent that rearrangement of atoms constituting the predetermined substance does not occur, the thin film forming method. 12. The thin film forming method according to claim 2 or 4, wherein the low temperature is equal to or higher than the Debye temperature of the predetermined substance. 13. A thin film forming method for forming a single crystal thin film of a predetermined substance on a substrate, comprising: an amorphous thin film, a polycrystalline thin film, or an axially oriented polycrystalline thin film of the predetermined substance on the substrate. Is formed in advance, and is a low energy gas that does not cause sputtering of the predetermined substance within a temperature range in which crystallization of the predetermined substance does not occur and at a temperature higher than the Debye temperature of the predetermined substance. The beam of the above is irradiated onto the amorphous thin film, the polycrystalline thin film, or the axially oriented polycrystalline thin film from a plurality of directions perpendicular to a plurality of close-packed planes of the single crystalline thin film to be formed. Method for forming thin film. 14. The thin film forming method according to claim 1, wherein the gas is an inert gas. 15. The thin film forming method according to claim 14, wherein the atomic weight of the element forming the inert gas exceeds the maximum atomic weight of the element forming the predetermined substance irradiated with the beam of the gas. A method for forming a thin film, which is characterized in that it does not exist. 16. The thin film forming method according to claim 15, wherein the atomic weight of the element forming the inert gas does not exceed the maximum atomic weight of the element forming the predetermined substance, and the atomic weight is the closest. A method for forming a thin film, characterized by being present. 17. The thin film forming method according to claim 1, wherein the gas is a gas substance containing an element that constitutes the predetermined substance. 18. The thin film forming method according to claim 1, wherein the reaction gas contains a gaseous substance containing an impurity element to be added to the predetermined substance. Method. 19. The thin film forming method according to claim 6, wherein the thin film including the plurality of layers is formed while maintaining the low temperature at a constant value. Method. 20. The claim 1, claim 2, or claim 5.
In the thin film forming method described in (1), the irradiation of the beam of gas is performed while a reflection plate for converging the beam of gas on the substrate is arranged around the substrate. Method. 21. The thin film forming method according to claim 6, wherein a reflective plate for converging the gas beam onto the substrate when performing the step (a) or (d). The method for forming a thin film, wherein the irradiation of the gas beam is performed while arranging the substrate around the substrate. 22. The thin film forming method according to claim 20 or 21, wherein at least a surface of the reflection plate which is irradiated with the gas beam is made of a material which does not cause sputtering due to the irradiation of the gas beam. And a thin film forming method. 23. The thin film forming method according to claim 20 or 21, wherein at least a surface of the reflection plate which is irradiated with the beam of gas is composed of an element constituting a substance on the uppermost surface of the substrate. And a thin film forming method. 24. The thin film forming method according to claim 6, wherein the steps (a) to (d) are performed.
However, when irradiating the beam of gas, it is possible to irradiate the beam of gas onto the substrate with low energy such that none of the layers already formed on the substrate cause sputtering. A characteristic thin film forming method. 25. The thin film forming method according to claim 6, wherein in each of the steps (a) to (d), the gas is added before the predetermined substance is deposited. A method for forming a thin film, comprising irradiating the substrate with the beam. 26. The thin film forming method according to claim 1, wherein the plasma is generated by using a microwave and the gas is radiated by a plasma irradiating device that guides the plasma to the substrate by a divergent magnetic field. A method for forming a thin film, which comprises obtaining a beam of 27. The thin film forming method according to claim 26, wherein the substrate is made of a conductive material, and the potential of the substrate is set to a desired value. 28. The thin film forming method according to claim 26, wherein among the electrons generated by the plasma irradiation apparatus, electrons that can substantially contribute to generation of a plasma sheath on the substrate are transferred to the substrate. A method for forming a thin film, characterized by using an electron blocking member for blocking flying. 29. The thin film forming method according to claim 1 or 3, wherein the low temperature is equal to or higher than the Debye temperature of the predetermined substance. 30. A thin film forming method for forming a single crystal thin film of a predetermined substance on a substrate, which is within a temperature range in which the crystallization of the predetermined substance does not occur and which is higher than the Debye temperature of the predetermined substance. In the process of depositing the predetermined substance on the substrate by supplying a reaction gas onto the substrate at a temperature, a beam of a low energy gas that does not cause sputtering of the predetermined substance is generated. A method for forming a thin film, which comprises irradiating onto the substrate from a plurality of directions perpendicular to a plurality of close-packed surfaces of the single crystal thin film to be formed. 31. The thin film forming method according to claim 6, wherein the low temperature in each of the steps (a) to (c) is equal to or higher than the Debye temperature of the predetermined substance. And a method for forming a thin film. 32. The thin film forming method according to claim 1, wherein the predetermined substance is silicon, the reaction gas contains silane gas as a main component, and the low temperature is 400 ° C. A thin film forming method characterized by the above. 33. A method of forming a single crystal thin film of silicon on a substrate, comprising a silane gas as a main component within a temperature range where crystallization of silicon does not occur and at a temperature of 400 ° C. or higher. In the process of depositing silicon on the substrate by supplying a reaction gas to the substrate, a beam of gas with low energy that does not cause sputtering of silicon is formed on the single crystal thin film to be formed. A method for forming a thin film, which comprises irradiating onto the substrate from a plurality of directions perpendicular to a plurality of densest surfaces. 34. The method for forming a thin film according to claim 6, wherein in the at least one of the steps (a) to (c), the predetermined substance is silicon. A method for forming a thin film, characterized in that the reaction gas contains silane gas as a main component and the low temperature is 400 ° C. or higher.