JP2002121660A - Method and apparatus for forming thin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for forming a carbon thin film excellent in adhesiveness to a substrate and film productivity. SOLUTION: In a first process, a substance containing atoms (e.g. carbon atom) constituting a thin film as a cathode substance 31 is used, in a gas atmosphere containing second atoms (e.g. silicon atom) different from the atom constituting the thin film, a plasma originating from the cathode substance and the gas is generated from the cathode substance by vacuum arc discharging, an intermediate film MF, which contains the atom constituting the thin film CF and the second atom under the plasma, has tight adhesion to both of a substrate W and the thin film CF, is formed, in a second process, a substance containing atoms (e.g. carbon atom) constituting a thin film as a cathode substance 31 is mainly used, the plasma originating from the cathode substance is generated from the cathode substance by vacuum arc discharging, the thin film (e.g. carbon thin film) is formed under the plasma.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and an apparatus for forming a thin film.

[0002]

2. Description of the Related Art In order to impart desired characteristics such as abrasion resistance and good slidability to a substrate surface of various articles, a thin film is widely formed on the substrate.

For example, carbon films such as a DLC (diamond-like carbon) film, an amorphous carbon film, and an amorphous diamond film have excellent abrasion resistance and slidability. It is formed on an article substrate that requires abrasion and / or good slidability.

[0004] Such carbon films have hitherto been used for plasma CVD.
It has been formed by the method.

However, the carbon film formed by the plasma CVD method is made of an iron-based material, an aluminum-based metal, a cemented carbide, a ceramic, etc., which are often used as base materials for automobile parts, machine parts, tools, molds and the like. Was not satisfactory in terms of adhesion.

For this reason, research and development have been made to form a carbon film having good adhesion. To illustrate one of them:
It has been proposed that a binder film having good adhesion to both the substrate and the carbon film be formed on the substrate by a general ion plating method or a sputtering method, and a carbon film formed on the binder film by a plasma CVD method. ing.

[0007]

However, all of the carbon film forming methods proposed and implemented so far, including the formation of a carbon film by a plasma CVD method, are still satisfactory in terms of adhesion to a substrate. In addition to what is not possible, the deposition rate is slow, especially over large areas, and is still not satisfactory in terms of carbon film productivity.

Although the formation of a carbon film has been described above as an example, generally speaking, a film which is still unsatisfactory in terms of film adhesion to a substrate and a film formation rate by a conventional film forming method is more and more. There is a demand for improved adhesion to substrates, and a further improvement in film forming speed.

Accordingly, an object of the present invention is to provide a method and an apparatus for forming a thin film which can be applied to the formation of various films, have excellent film adhesion to a substrate, and are excellent in film productivity.

Another object of the present invention is to provide a method and an apparatus for forming a thin film, particularly a method and an apparatus for forming a carbon thin film, which are excellent in film adhesion to a substrate and excellent in film productivity.

[0011]

Means for Solving the Problems The present inventor has repeated studies to solve the above problems, and a) forming an intermediate film containing atoms constituting the thin film having good adhesion to both the substrate and the target thin film; Forming a target thin film on the intermediate film, or b) forming a mixing layer of a substrate containing a thin-film constituent atom and a substrate having good adhesion to both the substrate and the target thin film on the substrate, Forming a desired thin film on the mixing layer, or c) forming a mixing layer between the substance containing atoms constituting the thin film and the substrate on the substrate after cleaning the substrate to improve the film adhesion to the substrate. Forming an intended thin film on the mixing layer, or forming an intermediate film containing thin film constituent atoms having good adhesion to both the mixing layer and the intended thin film on the mixing layer, Target on interlayer By forming any one of the methods of forming a thin film, and forming these intermediate films, mixing layers, and thin films of interest by vacuum arc evaporation,
It has been found that the adhesion to the substrate can be dramatically improved and the film productivity can be improved as compared with the conventional case.

The vacuum arc evaporation method uses a vacuum arc evaporation source that evaporates a cathode material by vacuum arc discharge to generate a plasma derived from the cathode material, and uses a vacuum arc evaporation source from the plasma generated by the vacuum arc evaporation source. In this method, ions contributing to the configuration of a thin film are drawn into a substrate or the like on which a film is to be formed under the application of a bias voltage, and a film is formed on the substrate or the like. It has the advantage of high film adhesion to substrates and the like.

The reason why the film formation rate is high is that a large amount of the cathode material can be evaporated using vacuum arc discharge. Can be formed. The film adhesion is high because the ions in the plasma can be strongly attracted to the substrate and the like by application of a film forming bias voltage such as a negative bias voltage to the substrate and the like, and can collide with the substrate and the like. .

The present invention provides the following first to fourth types of thin film forming methods and apparatuses based on such knowledge.

In any of the thin film forming methods and apparatuses described below, a thin film is formed using a vacuum arc evaporation method, so that a desired thin film can be formed on a substrate with good adhesion. Since the arc evaporation method is used, the film forming speed is high, and a film can be formed at a large film forming speed even in a large area, and the film productivity is high. Further, the target thin film is formed by (1) forming an intermediate film having adhesiveness to both the substrate and the target thin film on the substrate firmly with good adhesion by a vacuum arc vapor deposition method, Whether the target thin film is formed firmly with good adhesion by vacuum arc evaporation (in the case of the first and second types of thin film forming methods and apparatuses described below), or (2) the thin film constituent atoms and the base After the sputter cleaning of the substrate using the vacuum arc evaporation method, a mixing layer having adhesion to the substrate itself, in which the material is mixed, is formed on the substrate with good adhesion by the vacuum arc evaporation method,
Whether the target thin film is firmly formed on the mixing layer by vacuum arc evaporation with good adhesion (in the case of the following third type of thin film forming method and apparatus), or (3) forming such a mixing layer, An intermediate film having adhesiveness to both the mixing layer and the target thin film is formed on the mixing layer firmly and firmly by vacuum arc vapor deposition on the mixing layer. The thin film to be formed is firmly formed with good adhesion (in the case of the fourth type thin film forming method and apparatus described below), so that the adhesion of the target thin film to the substrate is further improved.

Any of the thin film forming methods and apparatuses described below can be applied to the formation of various films. For example, it can be used for forming (various metal films, nitride films, carbide films). A typical example is the formation of a carbon thin film.

Although the carbon thin film has poor adhesion to a metal substrate such as an iron-based or aluminum-based substrate, a substrate made of an alloy such as a cemented carbide, a ceramic substrate, etc., even such a material substrate may be used. According to the following method and apparatus for forming a thin film according to the present invention, a thin film can be formed with good adhesion and firmly. In particular, a hard carbon film having better adhesion than before can be formed on an iron-based metal substrate in which the adhesion of the carbon film is weak.

In each of the following types of thin film forming methods and apparatuses, the base for forming a carbon film is a metal base such as an iron base or an aluminum base, an alloy base such as a cemented carbide, or a ceramic base. Substrates selected from the substrates can be mentioned as typical examples. (1) First type thin film forming method and apparatus a) First type thin film forming method This is a thin film forming method for forming a target thin film on a substrate.
A first step of forming an intermediate film on the substrate by a vacuum arc deposition method, and forming the thin film on the intermediate film formed by the first step by a vacuum arc deposition method subsequent to the first step. The first step comprises using a substance containing the atoms constituting the target thin film and a second atom different from the atoms as a cathode material for causing a vacuum arc discharge. A vacuum arc discharge is generated from the cathode material to generate plasma derived from the cathode material, and the atoms including the atoms constituting the thin film and the second atoms under the plasma are adhered to both the substrate and the thin film. A good intermediate film is formed, and in the second step, a material mainly containing atoms constituting the target thin film is used as a cathode material for causing a vacuum arc discharge. Discharged thereby to generate plasma from the cathode material, a thin film forming method for forming a thin film to the object under the plasma.

The term "second atom" as used herein refers to an atom that is easily compatible with the substrate, in other words, is easily bonded to the substrate.
The intermediate film has good adhesion to the substrate by containing the second atoms, and has good adhesion to the target thin film by containing atoms constituting the thin film.

The same applies to the “second atom” and the “intermediate film” including the “second atom” used in the method and apparatus for forming a thin film described later.

According to the present invention, as the thin film forming method, in the first step, a silicon carbide intermediate film is formed by using a material containing carbon atoms and silicon atoms as the cathode material for causing a vacuum arc discharge. In the second step, a method for forming a carbon thin film using a material mainly containing carbon atoms (which may not contain silicon) as the cathode material for causing vacuum arc discharge is provided.

Since the silicon carbide intermediate film contains silicon, it can be formed with good adhesion even on substrates such as iron-based or aluminum-based metal substrates, alloy substrates such as cemented carbides, and ceramic substrates. Since it contains, it has good adhesion to the carbon thin film. b) Thin film forming apparatus of the first type This is a thin film forming apparatus for forming a target thin film on a substrate, and forms a vacuum vessel in which a substrate to be formed is placed, and an intermediate film on the substrate placed in the vacuum vessel. Vacuum arc evaporation source for forming the thin film of interest on an intermediate film formed by the first vacuum arc evaporation source, and a film forming bias on the base. A bias voltage applying device for applying a voltage, wherein the first vacuum arc evaporation source includes, as a cathode material for causing a vacuum arc discharge, an atom constituting the target thin film and a second atom different from the atom. The second vacuum arc evaporation source has a cathode material for forming a thin film mainly containing atoms constituting the thin film as a cathode material for causing vacuum arc discharge. The bias voltage applying device can apply a bias voltage for forming an intermediate film to the substrate when forming an intermediate film, and a bias voltage for forming a thin film when forming a thin film, and the first vacuum arc evaporation source can perform vacuum arc discharge from the cathode material. Forming a plasma derived from the cathode material, and applying both the substrate and the target thin film on the substrate to which a bias voltage for forming an intermediate film is applied from the bias voltage applying device under the plasma. The second vacuum arc evaporation source forms a plasma derived from the cathode material by causing a vacuum arc discharge from the cathode material, and the bias voltage is applied under the plasma. A thin film forming apparatus capable of forming the target thin film on an intermediate film on the substrate to which a thin film forming bias voltage is applied from an application device.

The present invention is particularly directed to such a thin film forming apparatus, wherein the first vacuum arc evaporation source has a cathode material for forming an intermediate film containing carbon atoms and silicon atoms as a cathode material for causing vacuum arc discharge. The second vacuum arc evaporation source has a cathode material for forming a thin film mainly containing carbon atoms (which may not contain silicon) as a cathode material for causing a vacuum arc discharge. A plasma derived from the cathode material is formed by performing a vacuum arc discharge from the cathode material, and a silicon carbide intermediate layer is formed on the substrate to which a bias voltage for forming an intermediate film is applied from the bias voltage applying device under the plasma. A film can be formed, and a plasma derived from the cathode material is formed by performing a vacuum arc discharge from the cathode material in the second vacuum arc evaporation source. , Under the plasma, to provide a carbon film forming apparatus capable of forming a carbon film on an intermediate layer on the bias voltage the substrate is applied a bias voltage for thin film formation from the application device.

The "vacuum vessel" can be set to a predetermined reduced-pressure atmosphere state in the inside thereof. Usually, the "vacuum container" is provided with an exhaust device, and the inside of the vacuum device can be set to a predetermined reduced pressure state. This applies to other types of thin film forming methods and apparatuses described below.

Each of the vacuum arc evaporation sources basically includes a cathode material for generating a vacuum arc discharge and a discharge power supply connected to the cathode material. This point also
The same applies to the method and apparatus for forming a thin film described below.

Here, the first and second vacuum arc evaporation sources may be partially configured in common.

The number of vacuum arc evaporation sources and / or the number of cathode materials belonging to each vacuum arc evaporation source are arbitrary. This is the same in the method and apparatus for forming a thin film described below. (2) Second type thin film forming method and apparatus a) Second type thin film forming method This is a thin film forming method for forming a target thin film on a substrate,
A first step of forming an intermediate film on the substrate by a vacuum arc vapor deposition method, and forming the intermediate film on the intermediate film formed by the first step by the vacuum arc vapor deposition method following the first step; A second step of forming a thin film, wherein in the first step, a material containing atoms constituting the thin film is used as a cathode material for causing a vacuum arc discharge, and is different from the atoms constituting the thin film. A vacuum arc discharge is generated from the cathode material in a gas atmosphere containing a second atom to generate plasma derived from the cathode material and the gas, and the plasma includes atoms forming the thin film and the second atoms under the plasma. An intermediate film having good adhesion is formed on both the base and the thin film, and in the second step, a material mainly containing atoms constituting the thin film is used as a cathode material for causing vacuum arc discharge. There was vacuum arc discharge from the cathode material to generate a plasma from the cathode material, a thin film forming method for forming a thin film to the object under the plasma.

In this thin film forming method, when the intermediate film is formed in the first step, the supply amount of the gas containing the second atom is gradually reduced from the beginning to the end of the formation of the intermediate film. An intermediate film having a higher content of the second atoms in a portion closer to the base than a portion far from the base, and having a higher content of thin-film constituent atoms in a portion closer to the thin film than a portion close to the base may be formed. Since the intermediate film has a large content of the second atom in a portion close to the substrate and a large content of atoms constituting the thin film in a portion near the thin film, the adhesion between the substrate and the target thin film is better. .

In the present invention, in particular, as the second type of thin film forming method, in the first step, a material containing a carbon atom (which may not contain silicon) is used as the cathode material for causing a vacuum arc discharge. And forming a silicon carbide intermediate film using a gas containing a silicon atom as the second atom or a gas containing the silicon atom and the carbon atom as the gas, and causing a vacuum arc discharge in the second step. A substance mainly containing carbon atoms as the cathode substance (silicon may not be contained)
Provided is a method for forming a carbon thin film using the method.

In the case where the carbon thin film is formed as described above, when forming the silicon carbide intermediate film in the first step, the gas containing the silicon atoms or the silicon atom is gradually increased from the beginning to the end of the formation of the intermediate film. And reducing the supply amount of the gas containing carbon atoms, the portion closer to the substrate has a higher content of silicon atoms than the portion far from the substrate, and the portion closer to the thin film has more carbon atoms than the portion closer to the substrate. An intermediate film having a large content can be formed. Such a silicon carbide intermediate film has better adhesion to both the substrate and the target carbon thin film. b) Thin film forming apparatus of the second type This is a thin film forming apparatus for forming a target thin film on a substrate,
A vacuum container for installing a substrate on which a film is to be formed, a vacuum arc evaporation source for forming an intermediate film and the target thin film on the substrate provided in the vacuum container, and a bias voltage for film formation applied to the substrate. A bias voltage applying device for performing the operation, and a second atom different from the atoms constituting the thin film in the vacuum vessel.
A gas supply device for supplying a gas containing atoms.The vacuum arc evaporation source is used for forming an intermediate film containing the thin film constituent atoms as a cathode material for causing vacuum arc discharge and for forming a thin film of interest. The bias voltage applying device can apply a bias voltage for forming an intermediate film to the substrate when forming an intermediate film, and a bias voltage for forming a thin film when forming a thin film. By performing a vacuum arc discharge and supplying a predetermined amount of the gas into the vacuum container from the gas supply device, a plasma derived from the cathode material and the gas is formed. By applying a voltage, on the substrate under the plasma, the substrate and the thin film have good adhesiveness, the thin film constituent atoms and The intermediate film containing the second atom can be formed, and then vacuum arc discharge is performed from the cathode material in the vacuum arc evaporation source to form a plasma derived from the cathode material, and a thin film is formed on the base from the bias voltage applying device. A thin film forming apparatus capable of forming the target thin film on the intermediate film on the base under the plasma by applying a bias voltage for use.

In order to further improve the adhesion of the intermediate film to the substrate and the target thin film, the gas supply device gradually forms the second film from the beginning to the end of the formation of the intermediate film when forming the intermediate film. A gas supply device capable of reducing the supply amount of gas containing atoms may be used.

The present invention is particularly directed to the second type of thin film forming apparatus, wherein the intermediate film and the thin film forming cathode material in the arc evaporation source contain carbon atoms (typically, a material mainly containing carbon atoms) ( And the gas supply device supplies a gas for forming a silicon carbide intermediate film, wherein the gas contains silicon atoms as the second atom or the silicon gas. A thin film forming apparatus capable of supplying a gas containing atoms and carbon atoms and forming a carbon thin film as the target thin film is provided.

In the case of this apparatus, when forming the silicon carbide intermediate film, the gas supply device gradually increases the gas containing the silicon atoms or the gas containing the silicon atoms and the carbon atoms from the beginning to the end of the formation of the intermediate film. It may be a gas supply device capable of reducing the supply amount of the gas.

In the first and second types of thin film forming methods and apparatuses described above, silicon atoms can be cited as a typical example of the second atoms. In particular, the substrate is made of a metal such as iron or aluminum. When the substrate is a substrate such as a substrate, an alloy substrate such as a cemented carbide, or a ceramic substrate, silicon atoms are preferred.

As an example of the gas containing silicon atoms,
A silane gas such as a monosilane gas and a disilane gas can be given. Examples of the gas containing a silicon atom and a carbon atom include a triethylsilane gas, a trimethylsilane gas, and a tetramethylsilane gas. Among them, tetramethylsilane gas is a danger of spontaneous ignition,
It is less toxic, has a boiling point of about 26 ° C. and is close to room temperature, and is easy to handle in these respects, which is preferable.

In forming a carbon thin film,
When a gas containing silicon atoms (including a gas containing silicon atoms and carbon atoms) is used, the cathode material that causes a vacuum arc discharge to form an intermediate film may be a material mainly containing carbon atoms, and may contain silicon. You don't need to be. Also, from this, it is not necessary to employ a plurality of types of cathode materials, so that a carbon film can be formed at a lower cost,
Further, a carbon film forming apparatus can be provided at low cost. Further, the productivity of the carbon film can be further improved by using a plurality of cathode materials mainly containing carbon atoms for forming the target carbon film.

The gas containing silicon atoms or the gas containing silicon atoms and carbon atoms described above is characterized in that a silicon carbide intermediate film is formed by a thin film forming method (carbon film forming method) and a thin film forming apparatus (carbon film forming apparatus) described later. The same is true for a gas containing silicon atoms or a gas containing silicon atoms and carbon atoms used for forming silicon or the like.

In the first and second types of thin film forming methods and apparatuses described above, a film is formed by using a vacuum arc evaporation method. A bias voltage for attracting ions contributing to the formation of a predetermined film to the substrate is applied to the substrate by a bias voltage applying device. Such a bias voltage is usually a negative bias voltage. Its size is about several tens to 500 volts. If the bias voltage is too low, the effect of applying the bias voltage is difficult to recognize, and if the bias voltage is too high, the temperature rise of the substrate due to the collision of ions with the substrate becomes large, and the substrate is likely to be thermally damaged. Occurs.

In the first and second types of thin film forming methods, in at least one of the first step and the second step, a pulsed negative voltage or a pulsed negative voltage for forming a film on the substrate is provided. And a voltage obtained by superimposing DC negative voltage. In the first and second types of thin film forming apparatuses, the bias voltage applying apparatus may further include a pulsed negative voltage for forming a film or a voltage obtained by superimposing a pulsed negative voltage and a DC negative voltage on the substrate. What can be applied may be used.

The application of such a pulsed negative voltage can further improve the film adhesion.

The magnitude of the pulsed negative voltage is as follows.
A pulse frequency of about 500 V to 10 kV can be exemplified, and a pulse frequency of the pulsed negative voltage can be about 100 Hz to 10 kHz. If the magnitude of the pulsed negative voltage or the pulse frequency is too small, the effect of the application of the pulsed negative voltage is difficult to recognize. Problems such as susceptibility to damage occur.

In each of the first and second types of thin film forming methods, in each of the first step and the second step, a plasma formed by arc discharge from the cathode material is curved by a magnetic field. A magnetic filter may be used, and the arrival of the coarse particles to the base may be suppressed by the magnetic filter. Also in the first and second types of thin film forming apparatuses, the first and second vacuum arc evaporation sources cause the plasma formed by the vacuum arc discharge from the cathode material to be curved by the magnetic field, and the roughening to the base is performed. A magnetic filter for suppressing the arrival of particles may be included.

Such coarse particles are mainly derived from the cathode material, but by preventing the coarse particles from reaching the substrate, the peeling of the coarse particles into the intermediate film or the target thin film can be prevented. It is possible to form an intermediate film and a target thin film having better adhesion. (3) Third-type thin-film forming method and apparatus a) Third-type thin-film forming method This is a thin-film forming method for forming a target thin film on a substrate.
Applying a cleaning bias voltage to the base while generating a plasma derived from the inert gas and the cathode material by performing a vacuum arc discharge from the cathode material containing atoms constituting the target thin film in an inert gas atmosphere, A cleaning step of sputter-cleaning the substrate with the plasma while suppressing the arrival of coarse particles derived from the cathode material to the substrate using a magnetic filter that bends the plasma by a magnetic field; and Reduce the supply amount of gas or stop the supply of the inert gas, generate a vacuum arc discharge from the cathode material to generate plasma derived from the cathode material and apply a mixing layer forming bias voltage to the substrate, Cathode to the substrate using a magnetic filter that bends the plasma by a magnetic field A mixing layer forming step of forming a mixing layer of the substrate and a substance containing thin film-constituting atoms derived from the cathode material on the substrate under the plasma while suppressing the arrival of coarse particles derived from the material; and The supply amount of the inert gas is reduced or the supply of the inert gas is stopped, and a vacuum arc discharge is performed from the cathode material to generate a plasma derived from the cathode material, and a thin film is formed on the substrate. Applying a bias voltage for the purpose, using a magnetic filter that bends the plasma by a magnetic field, while suppressing the arrival of the coarse particles derived from the cathode material to the base, the target on the mixing layer under the plasma while suppressing the arrival. A thin film forming step of forming a thin film.

The present invention particularly provides a method for forming a thin film,
The present invention provides a thin film forming method in which a material mainly containing carbon atoms is used as the cathode material, a mixing layer of a substrate and a material containing carbon is formed in the mixing layer forming step, and a carbon thin film is formed in the thin film forming step.

In any case, the cleaning bias voltage applied to the substrate in the cleaning step and the mixing layer formation bias voltage applied to the substrate in the formation of the mixing layer are, in short, voltages capable of performing sputter cleaning and mixing layer formation. Any voltage that does not cause a special problem may be used. Without limitation, negative 2
A voltage of about 000 V to 500 V can be exemplified. Both bias voltages may have the same magnitude. If the magnitude of the applied negative bias voltage is larger than 2000 V, heating of the substrate becomes remarkable, which is not preferable. If the voltage becomes lower than 500 V, it becomes difficult to perform sputter cleaning and mixing layer formation.

The inert gas atmosphere pressure in the cleaning step may be, for example, about 1 × 10 ⁻² Pa to 1 × 10 Pa. Examples of the inert gas atmosphere pressure in the mixing layer forming step include a lower gas atmosphere pressure and a stop of the supply of the inert gas. If an inert gas is supplied even during the formation of the mixing layer, the film can be sputter-removed with the inert gas ions even if a film having low adhesion may be formed on the substrate.

As the thin film forming bias voltage applied to the substrate in the thin film forming step, a negative voltage of about several tens volts to several hundred volts can be exemplified, and the inert gas atmosphere pressure is further reduced to about 1 × 10 ⁻³ Pa or Stopping the supply of the inert gas can be exemplified.

The bias voltage applied to the substrate in the cleaning step and the mixing layer forming step is generally a DC voltage. However, when the substrate is a substrate having low conductivity or an insulating substrate, a high frequency voltage is applied to the substrate. It may be applied.

In at least one of the mixing layer forming step and the thin film forming step, a pulsed negative voltage or a pulsed negative voltage and a DC negative voltage or a high frequency voltage are superimposed on the substrate as the bias voltage. The applied voltage may be applied.

By applying such a pulsed bias voltage, a mixing layer having excellent adhesion to a substrate can be formed,
Alternatively, a thin film having excellent adhesion to the mixing layer can be formed.

The magnitude of the pulsed negative voltage may be suitable for each step. However, in the mixing layer forming step, a voltage in the range of approximately −10 kV to the above-described DC negative voltage (−2000 V). (Voltage in the range of -500 V). When the pulse voltage becomes more negative than −10 KV, there is a concern that the base may be overheated or electromagnetic waves may be generated.

The pulse voltage applied in the thin film forming step is not limited to the above, but is generally from -2000 V to
-100 V can be exemplified.

In performing the cleaning step and the mixing layer forming step, instead of superimposing the pulse voltage on the DC voltage or the high frequency voltage, the DC voltage or the high frequency voltage and the pulse voltage may be alternately applied. Good. In this case, in the cleaning step and the mixing layer forming step, a DC voltage or a high-frequency voltage is applied to the substrate in an inert gas atmosphere, and a pulsed voltage is applied to the substrate in an inert gas-free atmosphere. Sputter cleaning by ions and mixing layer formation by ion-on derived from the cathode material are performed alternately.

Here, the sputter cleaning of the substrate will be further described. In the case where the substrate is an iron-based or aluminum-based metal substrate, or an alloy substrate made of a cemented carbide material, etc. Although the surface contaminated layer cannot be completely removed only by washing with an organic solvent, the sputter cleaning process using the vacuum arc evaporation method can sufficiently remove even the surface contaminated layer, and as a result, a thin film having high adhesion can be obtained.

In particular, in the case of an iron-based substrate, an oxide layer such as iron oxide formed on the surface is formed, in the case of an aluminum-based substrate, an oxide layer of aluminum oxide or the like is formed, and in the case of a cemented carbide substrate, a deposited cobalt layer is formed. However, since it is formed on the surface of the substrate and cannot be completely removed with an organic solvent, even if a thin film is formed thereon by a conventional method, a film having high adhesion cannot be obtained. By the cleaning treatment, even the surface contamination layer is sufficiently removed, and as a result, a thin film having high adhesion is obtained.

In the case where a carbon-containing thin film is formed, the generation of coarse particles is particularly remarkable. However, the use of a magnetic filter can sufficiently suppress the arrival of such coarse particles to the substrate, thereby forming a good film with good adhesion.
These effects relating to sputter cleaning and the effect of using the magnetic filter can be similarly obtained in a third type thin film forming apparatus and a fourth type thin film forming method and apparatus described later. b) Thin film forming apparatus of the third type This is a thin film forming apparatus for forming a target thin film on a substrate,
A vacuum container for installing a substrate on which a film is to be formed, and a vacuum for cleaning a substrate provided in the vacuum container, forming a mixing layer on the cleaning substrate, and forming the target thin film on the mixing layer. An arc evaporation source, a bias voltage application device for applying a bias voltage to the substrate, and an inert gas supply device for supplying an inert gas into the vacuum vessel, wherein the vacuum arc evaporation source is
A cathode material containing the constituent atoms of the thin film as a cathode material that causes vacuum arc discharge, and a plasma generated by vacuum arc discharge from the cathode material is curved by a magnetic field to suppress the arrival of coarse particles to the base. A magnetic filter, wherein the bias voltage applying device applies a cleaning bias voltage to the substrate when cleaning the substrate, a mixing layer forming bias voltage when forming the mixing layer, and a thin film forming bias voltage when forming the thin film. The vacuum arc evaporation source is capable of applying a vacuum arc discharge from a cathode material in an inert gas atmosphere supplied in a predetermined amount from the inert gas supply device into a vacuum vessel to generate a plasma derived from the inert gas and the cathode material. And a cleaning bias voltage is supplied from the bias voltage applying device. The substrate to be applied can be sputter-cleaned by the plasma while suppressing the arrival of coarse particles derived from the cathode material to the substrate by the magnetic filter, and the inert gas supply from the inert gas supply device is shorter than during the sputter cleaning. While the amount is reduced or the supply of the inert gas is stopped, a vacuum arc discharge is generated from the cathode material to generate plasma derived from the cathode material, and a bias voltage for mixing layer formation is applied from the bias voltage application device. A mixing layer of the substrate and a material containing thin-film constituent atoms derived from the cathode material under the plasma while suppressing the arrival of coarse particles derived from the cathode material to the substrate by the magnetic filter; The inert gas supply amount from the inert gas supply device is reduced or the inert gas supply from the inert gas supply device as compared to when the mixing layer is formed. Under a stopped state, a vacuum arc discharge is generated from the cathode material to generate plasma derived from the cathode material, and the magnetic layer is formed on the mixing layer on the substrate to which a bias voltage for thin film formation is applied from the bias voltage applying device. A thin film forming apparatus capable of forming the target thin film under the plasma while suppressing the arrival of coarse particles derived from the cathode material to the substrate by the filter.

In particular, the present invention relates to this thin film forming apparatus,
The vacuum arc evaporation source has a material mainly containing carbon atoms as the cathode material, a thin film capable of forming a mixing layer of a substrate and a material containing carbon as the mixing layer, and a carbon film as the thin film as the object. A forming device is provided.

As the bias voltage applying device, for example, a device capable of appropriately applying various bias voltages described in the third type thin film forming method can be adopted.

For example, the bias voltage applying device applies a pulsed negative voltage or a voltage obtained by superimposing a pulsed negative voltage and a DC negative voltage to the substrate during at least one of the step of forming the mixing layer and the step of forming the thin film. It may be something that can be done.

As the pulsed negative voltage in this case, for example, various pulsed negative voltages described in the third type thin film forming method can be adopted. (4) Fourth type thin film forming method and apparatus a) Fourth type thin film forming method This is a thin film forming method for forming a target thin film on a substrate.
Applying a cleaning bias voltage to the base while generating a plasma derived from the inert gas and the cathode material by performing a vacuum arc discharge from the cathode material containing atoms constituting the target thin film in an inert gas atmosphere, A cleaning step of sputter cleaning the substrate with the plasma while suppressing the arrival of coarse particles derived from the cathode material to the substrate by using a magnetic filter that bends the plasma by a magnetic field; and atoms and the atoms constituting the thin film. Forming a mixing layer of a substance containing a second atom different from the substrate and the substrate cleaned by sputter cleaning, and an intermediate film on the mixing layer containing atoms constituting the thin film and the second atom different from the atoms. Forming a mixing layer and an intermediate film, and forming a thin film on the intermediate film to form the target thin film In the step of forming a mixing layer and an intermediate film, a vacuum arc is generated from the cathode material in an atmosphere of a gas for forming a mixing layer and an intermediate film that includes a second atom different from the atoms constituting the thin film. The gas and the cathode substance-derived plasma are generated by discharging, and a mixing layer forming bias voltage and an intermediate film forming bias voltage are sequentially applied to the substrate in this order,
A mixing layer and an intermediate film are sequentially formed under the plasma on the base while suppressing the arrival of the coarse particles derived from the cathode material to the base using a magnetic filter that bends the plasma by a magnetic field, and the thin film is formed. In the step, the cathode material is subjected to vacuum arc discharge to generate plasma derived from the cathode material, and a bias voltage for forming a thin film is applied to the substrate, and the cathode is applied to the substrate using a magnetic filter that bends the plasma by a magnetic field. A thin film forming method for forming the target thin film on the intermediate film under the plasma while suppressing the arrival of coarse particles derived from a substance.

At the stage of finally forming a target thin film, the cathode material is subjected to vacuum arc discharge in an inert gas atmosphere (for example, in a smaller amount of inert gas atmosphere than at the time of sputter cleaning) to form the inert gas. Alternatively, a plasma derived from the cathode material may be generated, and a target thin film may be formed under the plasma.

When the intermediate film is formed, the supply amount of the gas containing the second atom is gradually reduced from the beginning to the end of the formation of the intermediate film. An intermediate film having a higher content of two atoms and being closer to the thin film may be formed to have a higher content of atoms constituting the thin film than a portion closer to the base.

In the present invention, in particular, as the fourth type of thin film forming method, a material mainly containing carbon atoms is used as the cathode material, and in the mixing layer and intermediate film forming step, the gas for forming the mixing layer and the intermediate film is used. Using a gas containing silicon atoms or a gas containing carbon atoms and silicon atoms, forming a mixing layer of a substance containing carbon atoms and silicon atoms and a substrate as a mixing layer, forming a silicon carbide intermediate film as an intermediate film, In the thin film forming step, a thin film forming method for forming a carbon film as the target thin film is provided.

In the case of forming a carbon thin film as described above, when forming the silicon carbide intermediate film in the formation of the intermediate film, the gas containing silicon atoms or the silicon atom and the carbon atoms is gradually increased from the beginning to the end of the formation of the intermediate film. By reducing the supply amount of gas containing, the content of silicon atoms is higher at a portion near the base than at a portion far from the base, and the content of carbon atoms is higher at a portion closer to the thin film than a portion near the base. A large number of intermediate films may be formed.

As the bias voltage applied to the substrate in the cleaning step, the mixing layer forming step, and the thin film forming step, for example, the same bias voltage as described in the third type thin film forming method can be employed.

As the bias voltage for forming the intermediate layer applied to the substrate in forming the intermediate film, the same voltage as the bias voltage for forming the thin film in the thin film forming step can be employed.

In at least one of the mixing layer forming step, the intermediate film forming step and the thin film forming step, a pulsed negative voltage or a pulsed negative voltage and a DC negative voltage are superimposed on the substrate as the bias voltage. The applied voltage may be applied.

In this case, as the pulsed negative voltage, for example, various pulsed negative voltages described in the third type thin film forming method can be adopted depending on the process. b) Fourth type thin film forming apparatus A thin film forming apparatus for forming a target thin film on a substrate,
A vacuum vessel for installing the substrate on which the film is to be formed, and cleaning the substrate placed in the vacuum vessel, forming a mixing layer on the cleaning substrate, forming an intermediate film on the mixing layer, and forming an intermediate film on the intermediate film. A vacuum arc evaporation source for forming the target thin film, a bias voltage application device for applying a bias voltage to the substrate, and an inert gas supply device for supplying an inert gas into the vacuum vessel, A mixing layer between a substance containing atoms forming the thin film and a second atom different from the atoms and the substrate, and a mixing layer including atoms forming the thin film and the second atoms different from the atoms For forming an intermediate film on the layer, comprising a mixing layer and a gas supply device for forming an intermediate film, which supplies a gas for forming a mixing layer and the intermediate film into the vacuum vessel,
The vacuum arc evaporation source has a cathode material containing the constituent atoms of the thin film as a cathode material for causing a vacuum arc discharge, and curves a plasma generated by the vacuum arc discharge from the cathode material by a magnetic field, and causes Includes a magnetic filter that suppresses the arrival of coarse particles,
The bias voltage applying device applies a bias voltage for cleaning to the substrate when cleaning the substrate, a bias voltage for forming a mixing layer when forming the mixing layer, a bias voltage for forming an intermediate film when forming the intermediate film, and a bias voltage for forming an intermediate film when forming the thin film. A bias voltage for forming a thin film can be applied, and the vacuum arc evaporation source performs a vacuum arc discharge from the cathode material in an inert gas atmosphere supplied from the inert gas supply device into a vacuum vessel in a predetermined amount, thereby forming the inert gas. And generating a plasma derived from the cathode material and sputtering the substrate to which the cleaning bias voltage is applied from the bias voltage applying device with the plasma while suppressing the arrival of coarse particles derived from the cathode material to the substrate by the magnetic filter. The gas supply device for forming the mixing layer and the intermediate film can be cleaned. A vacuum arc discharge is generated from a cathode material in an atmosphere of a gas for forming a mixing layer and an intermediate film supplied in a predetermined amount into a vacuum vessel to generate plasma derived from the gas and the cathode material, and a mixing layer is formed from the bias voltage applying device. The bias voltage for the intermediate layer is successively applied to the substrate, and the mixing layer and the mixture under the plasma under the suppression of the arrival of the coarse particles derived from the cathode material to the substrate by the magnetic filter. An intermediate film can be sequentially formed, a vacuum arc discharge is generated from the cathode material to generate plasma derived from the cathode material, and a bias voltage for thin film formation is applied from the bias voltage applying device on the intermediate film on the base, The target thin film is formed under the plasma while suppressing the arrival of the coarse particles derived from the cathode material to the substrate by the magnetic filter. The thin film forming apparatus capable.

In the step of finally forming a target thin film, an inert gas is supplied from the gas supply device (for example, a smaller amount of inert gas is supplied than at the time of sputter cleaning) and the gas is supplied in the gas atmosphere. Vacuum arc discharge may be generated from the cathode material to generate plasma derived from the inert gas and the cathode material, and a target thin film may be formed under the plasma.

The mixing layer and the gas supply device for forming an intermediate film, when forming the intermediate film by the vacuum arc evaporation source, gradually reduce the supply amount of the gas containing the second atom from the beginning to the end of the formation of the intermediate film. Thus, an intermediate film having a higher content of the second atoms in a portion closer to the base than a portion far from the base, and having a higher content of constituent atoms of the thin film in a portion closer to the thin film than a portion close to the base can be formed. It may be something.

The present invention is particularly directed to a thin film forming apparatus of the fourth type, wherein the vacuum arc evaporation source has a material mainly containing carbon atoms as the cathode material, and the gas supply for the mixing layer and the intermediate layer is formed. The apparatus can supply a gas containing silicon atoms or a gas containing silicon atoms and carbon atoms, a mixing layer of a substance containing carbon atoms and silicon atoms and a substrate as the mixing layer, and a silicon carbide intermediate film as the intermediate film. And a thin film forming apparatus capable of forming a carbon film as the target thin film.

In the case of this apparatus, the gas supply device for forming the mixing layer and the intermediate film forms the gas or silicon gas containing the silicon atoms gradually from the beginning to the end of the formation of the silicon carbide intermediate film by the vacuum arc evaporation source. The gas supply device may be capable of reducing the supply amount of the gas containing the silicon atoms and the carbon atoms.

As the bias voltage applying device, for example, a device capable of applying a bias voltage for forming an intermediate film in addition to appropriately applying various bias voltages described in the third type thin film forming method can be employed.

As the bias voltage for forming the intermediate film, for example, the same voltage as the bias voltage for forming the thin film can be employed.

In at least one of the mixing layer forming step, the intermediate film forming step and the thin film forming step, a pulsed negative voltage or a pulsed negative voltage and a DC negative voltage are superimposed on the substrate as the bias voltage. The applied voltage may be applied.

As the pulsed negative voltage in this case, for example, various pulsed negative voltages described in the third type thin film forming method can be adopted depending on the process.

[0077]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a basic configuration of an example of a thin film forming apparatus capable of implementing the first and second types of thin film forming methods, and FIG. 3 shows a third and fourth type of thin film forming methods. 1 shows a basic configuration of an example of a thin film forming apparatus that can execute the method and can also execute the second type of thin film forming method depending on how the method is used.

The thin film forming apparatus A shown in FIG.
And a first vacuum arc evaporation source 3 and a second vacuum arc evaporation source 3 '. The vacuum vessel 1 is grounded, and has a holder 11 in which the film-forming substrate W is installed.
The holder 11 can be rotated by a rotation drive device (not shown). The vacuum vessel 1 has an exhaust device 2 connected thereto.
Thus, the inside can be set to a predetermined reduced pressure atmosphere. A gas supply device 5 is further connected to the vacuum container 1, and a predetermined gas can be supplied from the gas supply device 5 into the vacuum container at a predetermined flow rate as needed.

The first vacuum arc evaporation source 3 has a cathode material 31 for causing a vacuum arc discharge in the vacuum vessel 1 and includes an arc discharge power supply 32 connected to the cathode material 31. An insulating member 30 is interposed between the cathode material 31 and the container wall.

The second vacuum arc evaporation source 3 ′ is
Cathode material 31 'for causing vacuum arc discharge in
And an arc discharge power supply 32 'connected to the cathode material 31'. An insulating member 30 'is interposed between the cathode material 31' and the container wall.

The holder 11 is connected to a bias voltage applying power supply 4 for applying a bias voltage to the substrate W to be formed, which is installed on the holder.

The thin film forming apparatus B shown in FIG. 3 is obtained by adding a magnetic filter 6 to the apparatus A shown in FIG. The magnetic filter 6 is configured such that a coil 61 is wound around a curved transport pipe 60 connected to the vacuum vessel 1 and communicating with the inside of the vessel, and a power supply 62 is connected to the coil. Power supply 6
By applying a current to the coil 61 from 2, a bending magnetic field can be formed. The bending magnetic field may be formed using a permanent magnet. The vacuum arc evaporation source 3 is provided at an end of the transport pipe 60 remote from the container 1. The second vacuum arc evaporation source 3 'in the device A is omitted. The other points are substantially the same as those of the device A shown in FIG. 1, and the substantially same parts as those of the device A are denoted by the same reference numerals as those of the device A.

According to the thin film forming apparatus A shown in FIG. 1, a target thin film can be formed on the substrate W as follows.

In one method, as the cathode material 31 in the first vacuum arc evaporation source 3, a material mainly containing atoms (for example, carbon atoms) constituting a target thin film is used, and the second vacuum arc evaporation source 3 'is used. Cathode material 31 'in
A substance (for example, a silicon atom) which contains an atom (for example, a carbon atom) constituting a target thin film and a second atom (for example, a silicon atom) which is a second atom different from the atom and which is easily adapted to the substrate W and is easily bonded. (Silicon carbide) is used.

The substrate W on which the film is to be formed is set on the holder 11, and the inside of the container 1 is set to a predetermined reduced pressure atmosphere necessary for film formation by the exhaust device 2.

In the vacuum arc evaporation source 3 ′, a voltage is applied from the arc power supply 32 ′ to the cathode material 31 ′ to cause a vacuum arc discharge, thereby forming a plasma derived from the cathode material 31 ′. Holder 11
, A bias voltage for forming an intermediate film is applied to the substrate W. As the bias voltage, for example, a DC negative voltage, a pulsed negative voltage, or a voltage obtained by superposing a pulsed negative voltage and a DC negative voltage is applied.

Thus, the ions in the plasma are attracted to the substrate W, and on the substrate W, an intermediate film having good adhesion containing atoms constituting the target thin film and a second atom different from the atoms (for example, silicon carbide) Intermediate film) MF (see FIG. 2)
Is formed.

While the vacuum arc evaporation source 3 ′ is stopped, a voltage is applied from the arc power source 32 to the cathode material 31 in the vacuum arc evaporation source 3 to cause a vacuum arc discharge, thereby forming a plasma derived from the cathode material 31. , Power supply 4
Then, a bias voltage for forming a target thin film is applied to the substrate W. As the bias voltage, a DC negative voltage, a pulsed negative voltage, or a voltage obtained by superimposing a pulsed negative voltage and a DC negative voltage is applied.

Thus, the ions in the plasma are attracted to the substrate W, and a desired thin film (for example, a carbon film) CF (see FIG. 2) is formed on the substrate W. The thin film (for example, carbon film) CF adheres well to the intermediate film (for example, silicon carbide intermediate film) MF, and thus has good adhesion to the substrate W.

In another method, a gas supply device 5 is used instead of the second vacuum arc evaporation source 3 '. As the cathode substance 31 in the first vacuum arc evaporation source 3, a substance mainly containing atoms (for example, carbon atoms) constituting a target thin film is used.
A gas (for example, tetramethylsilane) containing a second atom (for example, silicon atom) which is a second atom different from an atom constituting the target thin film and which is easily adapted to the substrate W and is easily bonded is used.

The substrate W on which the film is to be formed is placed on the holder 11, and the inside of the container 1 is depressurized by the exhaust device 2. A predetermined amount of gas is supplied from the gas supply device 5 into the container 1 to form a predetermined reduced-pressure gas atmosphere in the container 1.

In the vacuum arc evaporation source 3, the arc power source 3
2, a voltage is applied to the cathode material 31 to cause a vacuum arc discharge in a gas atmosphere, thereby forming the cathode material 31 and plasma derived from the gas, while the power source 4 supplies the holder 11
, A bias voltage for forming an intermediate film is applied to the substrate W. As the bias voltage, for example, a DC negative voltage, a pulsed negative voltage, or a voltage obtained by superposing a pulsed negative voltage and a DC negative voltage is applied.

Thus, the ions in the plasma are attracted to the substrate W, and on the substrate W, an intermediate film (for example, silicon carbide) containing atoms constituting the target thin film and a second atom different from the atoms having good adhesion. An intermediate film MF is formed. In forming the intermediate film, the gas supply amount may be gradually reduced to form an intermediate film in which the second atom content is gradually reduced.

Subsequently, the gas supply amount from the gas supply device 5 is reduced or the gas supply is stopped, and the vacuum arc evaporation source 3
In the above, a voltage is applied from the arc power source 32 to the cathode material 31 to cause a vacuum arc discharge, thereby forming plasma mainly derived from the cathode material 31, while the power source 4 supplies the substrate W
, A bias voltage for forming a thin film is applied. As the bias voltage, a DC negative voltage, a pulsed negative voltage, or a voltage obtained by superimposing a pulsed negative voltage and a DC negative voltage is applied.

Thus, the ions in the plasma are attracted to the substrate W, and a desired thin film (for example, a carbon film) CF (see FIG. 2) is formed on the substrate W. The thin film (for example, carbon film) CF adheres well to the intermediate film (for example, silicon carbide film) MF, and thus has good adhesion to the substrate W.

In any of the above-described methods, in forming the intermediate film MF and the target thin film CF, the holder W is rotated as necessary to form the substrate W.
May be rotated.

According to the thin film forming apparatus B shown in FIG. 3, a target thin film can be formed on the substrate W as follows.

In one method, a material mainly containing atoms (for example, carbon atoms) constituting a target thin film is used as the cathode material 31 in the first vacuum arc evaporation source 3. An inert gas is used as a gas supplied from the gas supply device 5.

The substrate W for film formation is set on the holder 11, and the inside of the container 1 is depressurized by the exhaust device 2. A predetermined amount of inert gas is supplied from the gas supply device 5 into the container 1,
A predetermined reduced pressure inert gas atmosphere is formed therein.

In the magnetic filter 6, the coil 61 is energized from the power supply 62 to form a bending magnetic field in the bending transport pipe 60.

In the vacuum arc evaporation source 3, the arc power source 3
2 to apply a voltage to the cathode material 31 to cause a vacuum arc discharge in an inert gas atmosphere, thereby forming a plasma derived from the cathode material 31 and the inert gas. A cleaning bias voltage is applied to the substrate W. As the bias voltage, for example, a DC negative voltage, a pulsed negative voltage, or a voltage obtained by superposing a pulsed negative voltage and a DC negative voltage is applied.

Thus, the inert gas ions in the plasma are made to collide with the substrate W while the coarse particles are prevented from reaching the substrate W by the action of the bending magnetic field, and the surface of the substrate W is sputter-cleaned.

Subsequently, while the voltage is applied to the cathode material 31 in the vacuum arc evaporation source 3, the supply amount of the inert gas from the gas supply device 5 is reduced or the gas supply is stopped to mix the bias voltage applied to the substrate W. The bias voltage is used for forming a layer (may be the same as the bias voltage for cleaning). As the bias voltage, for example, a DC negative voltage, a pulsed negative voltage, or a voltage obtained by superposing a pulsed negative voltage and a DC negative voltage is applied.

Thus, while the coarse particles are prevented from reaching the substrate W by the action of the bending magnetic field, a mixing layer of the substrate material and the substance containing the constituent atoms (for example, carbon atoms) of the target thin film is formed on the substrate W. MX (see FIG. 4) is formed with good adhesion.

Further, while the voltage is applied to the cathode material 31 in the vacuum arc evaporation source 3, the gas supply device 5
The supply amount of the inert gas from the substrate is further reduced or the gas supply is stopped, and the bias voltage applied to the substrate W is set as the bias voltage for forming the target thin film CF (see FIG. 4). As the bias voltage, for example, a DC negative voltage, a pulsed negative voltage, or a voltage obtained by superposing a pulsed negative voltage and a DC negative voltage is applied.

Thus, the target thin film (for example, carbon film) CF is formed on the mixing layer MF of the base W while the coarse particles are prevented from reaching the base W by the action of the bending magnetic field. The thin film CF adheres well to the mixing layer MX, and thus has good adhesion to the substrate W.

In another method, the gas supply device 5
Therefore, it is a second atom different from the atoms constituting the target thin film and is familiar to the mixing layer MX.
An intermediate film forming gas (for example, tetramethylsilane) containing a second atom (for example, silicon atom) which is easily bonded can be supplied instead of the inert gas.

In the same manner as described in the above one method, the substrate is subjected to the sputter cleaning treatment, and then the gas supply from the gas supply device 5 is switched to the intermediate film formation gas supply, and the mixing layer formation bias voltage is applied to the substrate W. Is applied. Thus, while the coarse particles are prevented from reaching the substrate W by the action of the bending magnetic field, a mixing layer (substrate material) containing a substance containing the atoms (for example, carbon atoms) and the second atoms (for example, silicon atoms) constituting the thin film ( MX) is formed.

Subsequently, while the voltage is applied to the cathode material 31 in the vacuum arc evaporation source 3, an intermediate film forming gas is supplied from the gas supply device 5, and an intermediate film forming bias voltage is applied to the substrate W. This bias voltage may be the same as the next thin film forming bias voltage. As the bias voltage,
For example, a DC negative voltage, a pulsed negative voltage, or a voltage obtained by superimposing a pulsed negative voltage and a DC negative voltage is applied.

Thus, an intermediate film (for example, a silicon carbide intermediate film) MF (see FIG. 5) is formed on the mixing layer MX with good adhesion while suppressing the coarse particles from reaching the substrate W by the action of the bending magnetic field. You. This intermediate film MF contains thin film constituent atoms familiar to the target thin film CF (see FIG. 5) and second atoms familiar to the mixing layer MX. In the formation of the intermediate film, the gas supply amount may be gradually reduced to form an intermediate film in which the second atom content is gradually reduced.

Subsequently, while the voltage is applied to the cathode material 31 in the vacuum arc evaporation source 3, the gas supply device 5
The supply of gas from the substrate is stopped and the bias voltage applied to the substrate W is set as the bias voltage for forming the target thin film CF (see FIG. 5). As the bias voltage, for example, a DC negative voltage, a pulsed negative voltage, or a voltage obtained by superposing a pulsed negative voltage and a DC negative voltage is applied.

Thus, the target thin film (for example, carbon film) CF is converted to the intermediate film (for example, silicon carbide intermediate film) M while the coarse particles are prevented from reaching the substrate W by the action of the bending magnetic field.
Formed on F. The thin film CF adheres well to the intermediate film MF, and thus has good adhesion to the substrate W.

In this thin film formation, the cleaning process and the mixing layer forming process can be omitted, and the intermediate film forming process and the thin film forming process can be performed to form a thin film having good adhesion to the substrate W.

In any of the above-described methods, in the cleaning process, the mixing layer forming process, the intermediate film forming process, and the thin film forming process, the substrate W may be rotated by rotating the holder 11 as necessary. Good.

Next, an experimental example in which a carbon thin film is formed on a substrate W made of chromium molybdenum steel (JIS: SCM415), which is an example of a metal substrate, will be described. (1) Experimental Example 1 Gas supply device 5 without using second vacuum arc evaporation source 3 '
The first step and the second step were performed under the following conditions using a thin film forming apparatus A capable of supplying tetramethylsilane from a substrate, thereby forming a carbon film on the substrate.

In both the first step and the second step, the cathode material 31 of the first vacuum arc evaporation source 3 is graphite, and generates a vacuum arc discharge with an arc current of 100A.
The bias voltage applied to the substrate W is a negative DC voltage of -100V. (First step) Atmosphere in vacuum vessel 1: 5 × 10 ^{−1 of} tetramethylsilane
Pa atmosphere A silicon carbide intermediate film is formed to a thickness of 500 nm at a film forming rate of 70 nm / min. (Second step) Atmosphere in the vacuum vessel 1: The introduction of tetramethylsilane was stopped and kept at 5 × 10 ⁻³ Pa or less.

A carbon film is formed on the intermediate film at a deposition rate of 70 nm / m.
500 nm thick in. (2) Experimental Example 2 In Experimental Example 1, when forming the intermediate film in the first step, an atmosphere of 5 × 10 ^-1 Pa of tetramethylsilane was formed in the vacuum vessel 1, and then the atmosphere of 6 × 10 ^-2 Pa / min was formed. The introduction amount of tetramethylsilane is reduced in proportion, and the introduction is finally stopped to form a graded silicon carbide intermediate film at an average film forming rate of 60%.
500 nm thick at nm / min.

The other conditions were the same as in Experimental Example 1, and finally a carbon film was formed at a film formation rate of 50 nm / min and a thickness of 500 nm. (3) Experimental Example 3 Using a thin film forming apparatus B capable of supplying tetramethylsilane from the gas supply apparatus 5, a first step and a second step are performed under the following conditions to form a carbon film on the substrate. did.

In both the first step and the second step, the cathode material 31 of the first vacuum arc evaporation source 3 is graphite, and a vacuum arc discharge is generated with an arc current of 100A.
The bias voltage applied to the substrate W is a negative DC voltage of -100V. (First step) Atmosphere in vacuum vessel 1: 5 × 10 ^{−1 of} tetramethylsilane
After forming a Pa atmosphere, the introduction amount of tetramethylsilane was reduced at a rate of 6 × 10 ⁻² Pa / min, and the introduction was finally stopped.

A graded silicon carbide intermediate film is formed at a thickness of 500 nm at an average film forming speed of 60 nm / min. (Second step) A carbon film was finally formed at a film formation rate of 50 nm / min and a thickness of 500 nm in the same manner as in Experimental Example 1. (4) Experimental Example 4 Using the thin film forming apparatus B capable of selectively supplying argon gas and tetramethylsilane from the gas supply apparatus 5, the first to fourth steps were performed under the following conditions to form a substrate. Then, a carbon film was formed.

In each step, the cathode material 31 of the first vacuum arc evaporation source 3 is graphite, and the arc current 100
As A, a vacuum arc discharge is generated. The bias voltage applied to the substrate W is a negative DC voltage of -100V. (First Step) Atmosphere in the vacuum vessel 1: 5 × 10 ^-1 Pa atmosphere of argon gas The substrate W was sputter-cleaned by argon on. (Second step) After the introduction of argon gas was stopped and the atmospheric pressure in the container 1 was reduced to 5 × 10 ⁻³ Pa or less, tetramethylsilane was introduced to adjust the atmospheric pressure in the container 1 to 5 × 10 ⁻¹ Pa, and carbon And a mixing layer of silicon and a base material are formed on the base W. (Third step) Atmosphere in vacuum vessel 1: 5 × 10 ^{−1 of} tetramethylsilane
After forming a Pa atmosphere, the introduction amount of tetramethylsilane was reduced at a rate of 6 × 10 ⁻² Pa / min, and the introduction was finally stopped.

A graded silicon carbide intermediate film is formed at an average deposition rate of 60 nm / min and a thickness of 500 nm. (Fourth step) Atmosphere in vacuum vessel 1: 5 × 10 ^-2 P after stopping gas introduction
Keep below a.

A carbon film is formed on the intermediate film at a deposition rate of 50 nm / m.
500 nm thick in.

In addition to the above, the first example in Experimental Example 1
A comparative experimental example in which a carbon film was formed in the same manner as in Experimental Example 1 except the steps was omitted.

The films obtained in Experimental Examples 1 to 4 and Comparative Experimental Example described above were evaluated for adhesion by a scratch tester. The evaluation results are shown below. The higher the value of the critical load, the better the adhesion to the substrate.

[0127] From these evaluation results, it can be seen that according to the present invention, a thin film having good adhesion can be formed.

[0128]

As described above, according to the present invention, it is possible to provide a method and an apparatus for forming a thin film which can be applied to the formation of various films and have excellent film adhesion to a substrate and excellent film productivity. it can.

Further, according to the present invention, it is possible to provide a method and an apparatus for forming a thin film, particularly a method and an apparatus for forming a carbon thin film, which are excellent in film adhesion to a substrate and excellent in film productivity.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of an example of a thin film forming apparatus.

FIG. 2 is a view showing an example of a thin film obtained by a thin film forming method and apparatus according to the present invention.

FIG. 3 is a diagram showing a basic configuration of another example of the thin film forming apparatus.

FIG. 4 is a view showing another example of a thin film obtained by the method and apparatus for forming a thin film according to the present invention.

FIG. 5 is a view showing still another example of a thin film obtained by the method and apparatus for forming a thin film according to the present invention.

[Explanation of symbols]

 A, B Thin film forming apparatus 1 Vacuum container 2 Exhaust device 3 First vacuum arc evaporation source 30 Insulation member 31 Cathode material 32 Power supply 3 'Second vacuum arc evaporation source 30' Insulation member 31 'Cathode material 32' Power supply 4 Bias voltage application Power supply 5 Gas supply device 6 Magnetic filter 60 Curved transport pipe 61 Coil 62 Power supply W Base MF Intermediate film CF Target film MX Mixing layer

Claims (14)

[Claims] 1. A thin film forming method for forming a target thin film on a base, comprising: a first step of forming an intermediate film on the base by a vacuum arc vapor deposition method; and an intermediate step formed by the first step. A second step of forming the target thin film on the film by a vacuum arc vapor deposition method subsequent to the first step, wherein the first step comprises carbon as a cathode material for causing a vacuum arc discharge. Using a substance containing atoms and silicon atoms, performing a vacuum arc discharge from the cathode substance to generate plasma derived from the cathode substance, forming a silicon carbide intermediate film under the plasma, and in the second step, , Using a material mainly containing carbon atoms as a cathode material for causing vacuum arc discharge,
A method for forming a thin film, comprising: generating a plasma derived from the cathode material by performing a vacuum arc discharge from the cathode material; and forming a carbon thin film as the target thin film under the plasma. 2. A thin film forming method for forming a target thin film on a base, comprising: a first step of forming an intermediate film on the base by a vacuum arc vapor deposition method; and an intermediate step formed by the first step. A second step of forming the target thin film on the film by a vacuum arc vapor deposition method subsequent to the first step, wherein the first step comprises carbon as a cathode material for causing a vacuum arc discharge. Using a material containing atoms, a vacuum arc discharge is generated from the cathode material in an atmosphere of a gas containing silicon atoms or a gas containing silicon atoms and carbon atoms to generate plasma derived from the cathode material and gas, and And forming a silicon carbide intermediate film, and in the second step, a substance mainly containing carbon atoms is used as a cathode substance for causing vacuum arc discharge,
A method for forming a thin film, comprising: generating a plasma derived from the cathode material by performing a vacuum arc discharge from the cathode material; and forming a carbon thin film as the target thin film under the plasma. 3. In each of the first step and the second step, a magnetic filter that bends a plasma formed by an arc discharge from the cathode material with a magnetic field is used, and the magnetic filter applies a coarse filter to the base. 3. The method for forming a thin film according to claim 1, wherein the arrival of particles is suppressed. 4. A thin film forming method for forming a target thin film on a substrate, comprising: performing a vacuum arc discharge from a cathode material containing atoms constituting the target thin film in an inert gas atmosphere; While generating a plasma derived from the cathode material, applying a cleaning bias voltage to the substrate, and using a magnetic filter that bends the plasma with a magnetic field, the base material is suppressed while suppressing the arrival of coarse particles derived from the cathode material to the substrate. A cleaning step of performing sputter cleaning with the plasma; or reducing the supply amount of the inert gas or stopping the supply of the inert gas from the time of the sputter cleaning, and performing a vacuum arc discharge from the cathode material to form the cathode material. And a bias voltage for forming a mixing layer is applied to the substrate. A substance containing thin film-constituting atoms derived from the cathode material and the substrate under the plasma while suppressing the arrival of coarse particles derived from the cathode material to the substrate using a magnetic filter that bends the magnetic field by a magnetic field. A mixing layer forming step of forming a mixing layer with, and reducing or stopping the supply of the inert gas than at the time of the mixing layer forming step, and causing a vacuum arc discharge from the cathode material. Generating a plasma derived from the cathode material and applying a bias voltage for forming a thin film to the substrate, and suppressing the arrival of coarse particles derived from the cathode material to the substrate using a magnetic filter that bends the plasma by a magnetic field. And forming a thin film of interest on the mixing layer under the plasma. 5. The method according to claim 1, wherein a material mainly containing carbon atoms is used as the cathode material, a mixing layer of a substrate and a material containing carbon is formed in the mixing layer forming step, and a carbon thin film is formed in the thin film forming step. 5. The method for forming a thin film according to 4. 6. A thin film forming method for forming a target thin film on a substrate, comprising: performing a vacuum arc discharge from a cathode material containing atoms constituting the target thin film in an inert gas atmosphere; While generating a plasma derived from the cathode material, applying a cleaning bias voltage to the substrate, and using a magnetic filter that bends the plasma with a magnetic field, the base material is suppressed while suppressing the arrival of coarse particles derived from the cathode material to the substrate. A cleaning step of sputter cleaning with the plasma; a mixing layer of a substance containing the atoms constituting the thin film and a second atom different from the atoms with a substrate subjected to the sputter cleaning; and the atoms constituting the thin film and the atoms A mixing layer and an intermediate layer forming an intermediate film on the mixing layer, wherein the mixing layer includes the second atom different from the second atom. A forming step, and a thin film forming step of forming the target thin film on the intermediate film, wherein the mixing layer and the intermediate film forming step include a second atom different from an atom constituting the thin film. A vacuum arc discharge is generated from the cathode material in an atmosphere of a gas for forming a mixing layer and an intermediate film to generate plasma derived from the gas and the cathode material, and a bias voltage for forming a mixing layer and a bias voltage for forming an intermediate film are formed on the substrate. Are sequentially applied in this order, and the mixing layer and the intermediate film are applied to the base under the plasma while suppressing the arrival of the coarse particles derived from the cathode material to the base using a magnetic filter that bends the plasma by a magnetic field. Are sequentially formed, and in the thin film forming step, a vacuum arc discharge is performed from the cathode material to generate plasma derived from the cathode material. Applying a bias voltage for forming a thin film to the substrate, using a magnetic filter that bends the plasma by a magnetic field, while suppressing the arrival of coarse particles derived from the cathode material to the substrate while the intermediate film is formed under the plasma. A method for forming a thin film, wherein the target thin film is formed thereon. 7. A material mainly containing carbon atoms as the cathode material, and in the step of forming the mixing layer and the intermediate film, a gas containing silicon atoms or a carbon atom and a silicon atom is used as a gas for forming the mixing layer and the intermediate film. Using a gas, a mixing layer of a substance containing carbon atoms and silicon atoms as a mixing layer and a substrate is formed, a silicon carbide intermediate film is formed as an intermediate film, and the carbon film is formed as the target thin film in the thin film forming step. The method for forming a thin film according to claim 6, wherein the thin film is formed. 8. A thin film forming apparatus for forming a target thin film on a substrate, comprising: a vacuum container for setting a substrate on which a film is to be formed; and a first container for forming an intermediate film on the substrate set in the vacuum container. A vacuum arc evaporation source; a second vacuum arc evaporation source for forming the target thin film on an intermediate film formed by the first vacuum arc evaporation source; and applying a film forming bias voltage to the substrate. And a first vacuum arc evaporation source having a cathode material for forming an intermediate film containing carbon atoms and silicon atoms as a cathode material for causing a vacuum arc discharge; The vacuum arc evaporation source has a cathode material for forming a thin film mainly containing carbon atoms as a cathode material for causing a vacuum arc discharge. A bias voltage for film formation, a bias voltage for thin film formation can be applied at the time of thin film formation, and a plasma derived from the cathode material is formed by performing a vacuum arc discharge from the cathode material in the first vacuum arc evaporation source. Originally, a silicon carbide intermediate film can be formed on the substrate to which a bias voltage for forming an intermediate film is applied from the bias voltage applying device, and a vacuum arc discharge is performed from the cathode material in the second vacuum arc evaporation source. A plasma derived from the cathode material is formed, and under the plasma, a carbon thin film can be formed on an intermediate film on the substrate to which a bias voltage for forming a thin film is applied from the bias voltage applying device. Thin film forming equipment. 9. A thin film forming apparatus for forming a target thin film on a substrate, comprising: a vacuum container for setting a substrate on which a film is to be formed; and an intermediate film and the target thin film on a substrate set in the vacuum container. A vacuum arc evaporation source for forming, a bias voltage applying device for applying a film forming bias voltage to the substrate, and a gas containing a second atom different from the atoms constituting the thin film in the vacuum vessel The vacuum arc evaporation source has the intermediate film mainly containing carbon atoms and the cathode material for forming the thin film as a cathode material for causing a vacuum arc discharge, and the bias The voltage application device can apply a bias voltage for forming an intermediate film to the base when forming an intermediate film, and a bias voltage for forming a thin film when forming a thin film. A gas containing silicon atoms and carbon atoms can be supplied, and a vacuum arc discharge is performed from the cathode material in the vacuum arc evaporation source, and a predetermined amount of the gas is supplied from the gas supply device into a vacuum vessel. Forming a plasma derived from a cathode material and a gas, and applying a bias voltage for forming an intermediate film from the bias voltage applying device to the substrate to form a silicon carbide intermediate film on the substrate under the plasma; A vacuum arc discharge from the cathode material in the vacuum arc evaporation source to form plasma derived from the cathode material, and applying a bias voltage for forming a thin film from the bias voltage applying device to the substrate to reduce the plasma. Wherein the carbon thin film can be formed on the intermediate film of the substrate. 10. The vacuum arc evaporation source includes a magnetic filter that curves plasma formed by vacuum arc discharge from a cathode material by a magnetic field and suppresses the arrival of coarse particles to the substrate. 10. The thin film forming apparatus according to 9. 11. A thin film forming apparatus for forming a target thin film on a substrate, comprising: a vacuum container for setting a substrate on which a film is to be formed; and cleaning the substrate set in the vacuum container; A vacuum arc evaporation source for forming the target thin film on the mixing layer, a bias voltage applying device for applying a bias voltage to the substrate, and an inert gas in the vacuum container. An inert gas supply device for supplying, the vacuum arc evaporation source has a cathode material containing the constituent atoms of the thin film as a cathode material for causing vacuum arc discharge, and a vacuum arc discharge from the cathode material. A magnetic filter for curving generated plasma by a magnetic field to suppress arrival of coarse particles to the base; Can apply a cleaning bias voltage to the substrate when cleaning the substrate, a mixing layer formation bias voltage when forming the mixing layer, and a thin film formation bias voltage when forming the thin film. A vacuum arc discharge is generated from the cathode material in an inert gas atmosphere supplied from the active gas supply device into the vacuum vessel in a predetermined amount to generate plasma derived from the inert gas and the cathode material. The substrate to which a bias voltage is applied can be sputter-cleaned by the plasma while suppressing the arrival of coarse particles derived from the cathode material to the substrate by the magnetic filter. The supply amount of the active gas was reduced or the supply of the inert gas was stopped. Under the condition, a vacuum arc discharge is generated from the cathode material to generate plasma derived from the cathode material, and the base to which the bias voltage for mixing layer formation is applied from the bias voltage applying device is applied to the base by the magnetic filter. A mixing layer of the substrate and a material containing thin-film constituent atoms derived from the cathode material can be formed under the plasma while suppressing arrival of coarse particles derived from the material, and the inert gas supply device can be formed more than when the mixing layer is formed. While reducing the amount of inert gas supplied from the apparatus or while stopping the supply of the inert gas, a vacuum arc discharge is generated from the cathode material to generate plasma derived from the cathode material, and the bias voltage applying device uses the bias voltage applying device to form a thin film. On the mixing layer of the substrate to which a bias voltage is applied, while suppressing arrival of coarse particles derived from the cathode material to the substrate by the magnetic filter, Thin film forming apparatus characterized by under the plasma to form a thin film to the object. 12. The vacuum arc evaporation source has a material mainly containing carbon atoms as the cathode material, a mixing layer of a substrate and a material containing carbon as the mixing layer, and a carbon layer as the target thin film. 12. The thin film forming apparatus according to claim 11, which can form a film. 13. A thin film forming apparatus for forming a target thin film on a substrate, comprising: a vacuum container for installing a substrate on which a film is to be formed; cleaning a substrate provided in the vacuum container; Forming an intermediate film on the mixing layer, a vacuum arc evaporation source for forming the target thin film on the intermediate film, and a bias voltage applying device for applying a bias voltage to the substrate An inert gas supply device that supplies an inert gas into the vacuum vessel; a mixing layer formed of a substance containing the atoms constituting the thin film and a second atom different from the atoms; A gas for forming a mixing layer and an intermediate film for forming an intermediate film on the mixing layer, the gas including an atom to be mixed and the second atom different from the atom; The vacuum arc evaporation source has a cathode material containing the constituent atoms of the thin film as a cathode material for causing vacuum arc discharge, and a vacuum from the cathode material. The plasma generated by the arc discharge is curved by a magnetic field, and includes a magnetic filter that suppresses the arrival of coarse particles to the substrate.The bias voltage applying device applies a cleaning bias voltage to the substrate when cleaning the substrate. The mixing layer forming bias voltage can be applied at the time of forming the mixing layer, the intermediate film forming bias voltage can be applied at the time of forming the intermediate film, and the thin film forming bias voltage can be applied at the time of forming the thin film. Cathode substance in an inert gas atmosphere supplied in a predetermined amount from the supply device into the vacuum vessel And generating a plasma derived from the inert gas and the cathode material by performing vacuum arc discharge from the substrate. The plasma can be sputter-cleaned while suppressing the arrival of particles, and a vacuum is applied from the cathode material in an atmosphere of a predetermined amount of the mixing layer and the intermediate film forming gas supplied into the vacuum vessel from the mixing layer and the intermediate film forming gas supply device. An arc discharge is performed to generate plasma derived from the gas and the cathode material, and a bias voltage for mixing layer formation and a bias voltage for intermediate film formation are successively applied from the bias voltage application device to the substrate to which the bias voltage for intermediate film formation is sequentially applied. Under the above plasma under the plasma, the coarse particles derived from the cathode material are prevented from reaching the substrate. A kissing layer and the intermediate film can be sequentially formed; a vacuum arc discharge is generated from the cathode material to generate plasma derived from the cathode material; and the intermediate voltage on the substrate to which a bias voltage for thin film formation is applied from the bias voltage application device. A thin film forming apparatus, wherein the target thin film can be formed on the film under the plasma while suppressing the arrival of coarse particles derived from the cathode material to the substrate by the magnetic filter. 14. The vacuum arc evaporation source has a material mainly containing carbon atoms as the cathode material, and the gas supply device for forming the mixing layer and the intermediate layer comprises a gas containing silicon atoms or a gas containing silicon atoms and carbon atoms. A gas containing atoms can be supplied, and a mixing layer of a substance containing carbon atoms and silicon atoms and a substrate can be formed as the mixing layer, a silicon carbide intermediate film can be formed as the intermediate film, and a carbon film can be formed as the target thin film. Item 14. A thin film forming apparatus according to item 13.