JP2812517B2 - Ion plating method and apparatus - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ion plating method and apparatus.

In the ion plating, the coating material particles generated by evaporating the coating material are ionized in plasma in a vacuum vessel, and the ions are accelerated toward the substrate surface by an electric field and deposited as a coating layer on the substrate surface. Technology.

[Conventional technology]

As a method of applying an electric field for ion acceleration in ion plating, a method of applying a DC voltage to an electrode for acceleration,
There is a method of applying a high frequency and utilizing a self-bias effect. However, when both or one of the substrate and the coating layer is an insulating material, there is a problem that ions cannot be sufficiently accelerated.

6 and 7 show a conventional ion plating apparatus using a DC electric field application method and a high frequency electric field application method, respectively. In both figures, 1 is a vacuum vessel, 2 is an electrode for ion acceleration, 3a is a power supply for applying a DC electric field, 3b is a power supply for applying a high-frequency electric field, 3c is a blocking capacitor, 4 is a substrate transport tray, 5 is a substrate, and 6 is an evaporator. Source, 7 is a high frequency coil, 8
Denotes an evaporation source power supply, 9 denotes a high-frequency power supply, 10 denotes an exhaust system, 11 denotes a gas introduction system, and 12 denotes a substrate transfer system.

For example, in the case of ion plating in which a coating layer is formed on a substrate while moving the insulating substrate, a method of applying a DC electric field to the accelerating electrode 2 involves ion acceleration between the accelerating electrode 2 and the insulating substrate 5. Electric field is generated,
Between the insulating substrate 5 and the evaporation source 6, a positive charge accumulates on the insulating substrate surface 5a, a so-called capacitor effect, so that the ion accelerating electric field disappears. Eventually, there was a problem that abnormal discharge occurred and the characteristics and adhesion strength of the coating layer were reduced.

In the method of applying a high-frequency electric field to the accelerating electrode,
A negative electric field is always generated on the insulating substrate surface 5a due to the self-bias effect, and abnormal discharge does not occur. However, in order to form a film while moving the insulating substrate, the distance between the accelerating electrode 2 and the insulating substrate 5 must be increased. In this case, the strength of the high-frequency electric field is attenuated by the ionized evaporant, that is, the plasma, so that the self-bias effect is weakened and the ion acceleration voltage is lowered, so that the ion acceleration is reduced and the coating layer is reduced. However, there is a problem that the characteristics and the adhesion strength of the resin are reduced.

The above problem occurs not only when the substrate is an insulating material but also when at least one of the substrate and the coating layer is an insulating material according to the same principle as described above. For example, when an insulating coating layer is deposited on a conductive substrate, the above-described phenomenon becomes significant as the deposition growth of the layer progresses.

[Problems to be solved by the invention]

An object of the present invention is to provide an ion plating method and apparatus capable of preventing abnormal discharge or the like and performing sufficient ion acceleration even when the substrate and / or the coating layer is an insulating material.

[Means for solving the problem]

According to the present invention, according to the present invention, in a vacuum vessel, coating material particles generated by evaporating a coating material are ionized to one polarity in plasma, and the ions are directed to an insulating substrate surface by an electric field. An ion plating method for accelerating and depositing as a coating layer on the substrate surface, wherein the substrate surface is irradiated with a charge of another polarity from a charge emission source provided in the vacuum vessel so that the substrate surface has a different polarity. This is achieved by an ion plating method, which comprises forming a potential difference between the ions and the substrate surface by charging, and accelerating the ions toward the substrate surface by an electric field generated by the potential difference. .

According to the present invention, the above object is also provided, in a vacuum vessel, a device for evaporating a coating material, a device for ionizing the evaporated coating material particles to one polarity in plasma, and a substrate in which the ions are insulated. An ion plating apparatus provided with an accelerating electric field generator for generating an electric field that accelerates toward the surface, wherein the accelerating electric field generator irradiates a charge of another polarity to the substrate surface to cause the other surface of the substrate to change. The present invention is also achieved by an ion plating apparatus including a charge emission source that forms a potential difference between the ions and the substrate surface by being charged to a polarity and generates the electric field by the potential difference.

The term “insulated substrate” refers to a substrate made of an insulating material (insulating substrate) and a substrate made of a conductive material that is electrically insulated from the surroundings (conductive substrate).

(Operation)

In the present invention, the coating raw material particles are ionized to one polarity, while the substrate deposition surface in the insulated state is irradiated with a charge of another polarity to constantly charge the substrate deposition surface to the other polarity. Abnormal discharge is prevented because no unipolar charge is accumulated on the upper side. Further, since no accelerating electrode is used, a uniform accelerating electric field can be applied to the substrate regardless of the positional relationship between the electrode and the substrate.

Therefore, even in ion plating in which at least one of the substrate and the coating layer is insulative and the coating layer is formed while moving the substrate, a sufficient ion accelerating effect is obtained, the film quality is good, and the thin film layer having strong adhesion strength is provided. Is formed.

 Hereinafter, the present invention will be described in more detail with reference to Examples.

Embodiment 1 FIG. 1 shows an example of an ion plating apparatus according to the present invention. In the apparatus shown in the figure, an insulating substrate 5 is mounted on a substrate transport tray 4 in a vacuum vessel 1, an evaporation source 6 for evaporating a thin film forming material, which is a coating material, and an evaporation source for ionizing the evaporated thin film forming particles. An electron emission source 20 for irradiating electrons toward the high-frequency coil 7 placed directly above the source and the vapor deposition surface 5a of the insulating substrate 5 is provided.

FIG. 2 shows a configuration example of the electron emission source 20. Electron emission source 20
Are filaments 21 and 21 that emit thermoelectrons
A Wehnelt 22 placed at the same potential as the above, a grid 23 grounded to accelerate the emitted thermoelectrons, and a DC power supply 25 for setting the filament 21 to a negative potential to accelerate the thermoelectrons,
It comprises an AC power supply 26 for heating the filament to emit thermoelectrons.

In FIG. 1, 8 is an evaporation source power supply, 9 is a high-frequency electrode,
Reference numeral 10 denotes an exhaust system, 11 denotes a gas introduction system, and 12 denotes a substrate transfer system.

As described above, the device of the present invention does not include the ion acceleration electrode, but instead includes the electron emission source 20 that irradiates electrons to accelerate ions.

Next, an example of implementing the method of the present invention using the above-described apparatus will be described.

The material for forming an insulating thin film such as TiO ₂ or SiO ₂ evaporates in the evaporation source 6 and becomes a plasma state by high-frequency discharge by the high-frequency coil 7 together with Ar and O ₂ gas introduced from the gas introduction system 11. The thin film forming particles as particles are partially ionized.

The electron emission source 20 is a source of electrons. Filament 21
Are accelerated by a potential difference generated between the Wehnelt 22 and the grid 23, and radiated to the insulating substrate deposition surface 5a. The vaporized surface 5a is charged to a negative potential by the irradiated thermal electrons. By the electric field formed by this, the ionized thin film forming particles are accelerated, and the deposition surface 5a is accelerated.
To form an insulating thin film layer.

An SiO ₂ thin film layer as a coating layer was formed on a glass substrate by the above method.

Using 100 mm × 100 mm tempered glass as the insulating substrate 5 and SiO ₂ as the material for forming the insulating thin film, the pressure is 1 × 10 ⁻³ Pa or more.
High-frequency discharge was caused at 4 × 10 ⁻² Pa to convert SiO ₂ into plasma. The high frequency output at this time was 300 W.

The electron emission source 20 was arranged at a position approximately 500 mm diagonally below the glass substrate 5 and aimed at the center of the glass plate 5. Electrons of 100 mA were emitted from the filament 21, and a 4 kV potential difference was applied between the Wehnelt 22 and the grid 23 to accelerate the electrons and irradiate the glass substrate deposition surface 5a.

At this time, the glass substrate evaporation surface 5a of 100 mm x 100 mm is about -50
It was charged to a negative potential of 0V.

In this state, a film was formed at a film formation rate of 1.7 ° / S for 10 minutes. During film formation, abnormal discharge due to charge-up of positive charges did not occur.

For comparison, a film was formed in the same manner as above, but without electron irradiation.

In order to evaluate the abrasion resistance of each formed SiO ₂ thin film layer, the haze value after abrasion was measured 1000 times using a Taber-type abrasion tester.

The abrasion resistance evaluation was performed according to the abrasion resistance test method of JIS R 3211 (automotive safety glass) and JIS R 3212 (automotive safety glass test method). The results are shown in FIG. As a comparison, the haze value was 3.2% even when the electron irradiation from the electron emission source 20 was not performed. However, according to the present invention, the glass substrate deposition surface 5a was charged to a negative potential by the electron irradiation from the electron emission source 20. The haze was 1.9%. It has been confirmed that the ion plating method by electron irradiation according to the present invention is effective for forming a thin film layer having high wear resistance.

Embodiment 2 FIG. 4 shows another configuration example of the ion plating apparatus according to the present invention.

In the present embodiment, the conductive substrate 30 is held in an insulated state between the conductive substrate 30 and the substrate carrying tray 4 by the insulating table 32. As a result, the electrons irradiated from the electron emission source 20 do not leak to the substrate carrying tray 4, and the conductive substrate 30 is charged efficiently. This embodiment is particularly suitable for forming an insulating thin film layer on the conductive substrate 30. Of course, a conductive thin film layer can be formed on a conductive substrate by using this apparatus configuration as in the conventional method.

Embodiment 3 FIG. 5 shows another configuration example of the ion plating apparatus according to the present invention.

In this embodiment, the substrate transfer system as in the first and second embodiments is not provided. As described above, the present invention is also effective in the case where the film is formed while the substrate transport system is removed and the substrate 30 is fixed, without performing the film formation while moving the substrate 30 when performing the film formation.

In the ion plating apparatus of the present invention,
Electron emission sources not only emit thermionic electrons by heating the filament, but also emit thermionic electrons by heating the plate cathode by the electron impact method, and emit the electrons using hollow cathode discharge. Any structure can be used as long as it can emit electrons, not limited to thermoelectrons, and its structure and shape can be determined as needed. The irradiation position of the electron emission source may be any position as long as it can aim at the substrate, and is not particularly limited.

〔The invention's effect〕

As described above, according to the present invention, the substrate and / or
Alternatively, even if the coating layer is an insulating material, since abnormal discharge and the like can be prevented and sufficient ion acceleration can be performed, a coating layer having good characteristics and sufficient adhesion strength can be formed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of an ion plating apparatus according to the present invention. FIG. 2 is a cross-sectional view showing an example of an electron emission source of the ion plating apparatus according to the present invention. FIG. 4 is a graph showing the relationship between the frequency of wear and the haze value of an SiO ₂ coating layer formed on a glass substrate. FIG. 4 is a cross-sectional view showing another example of an ion plating apparatus according to the present invention. FIG. 6 is a sectional view showing another example of the ion plating apparatus according to the present invention, FIG. 6 is a sectional view showing a conventional DC electric field application type ion plating apparatus, and FIG. It is sectional drawing which shows an electric field application type ion plating apparatus. DESCRIPTION OF SYMBOLS 1 ... Vacuum container, 2 ... electrode for ion acceleration, 4 ... Substrate transfer tray, 5 ... Substrate, 6 ... Evaporation source, 7 ... High frequency coil, 10 ... Exhaust system, 11 ... Gas introduction system , 20 ... Emission source, 21 ... Thermionic emission filament, 22 ... Wehnelt, 23 ... Grid.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Hasegawa 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Tatsuhiko Shimizu 1 Toyota Town Toyota City, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation ( 56) References JP-A-61-6271 (JP, A) JP-A-61-67766 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C23C 14/00-14/58

Claims (2)

(57) [Claims] In a vacuum vessel, coating material particles produced by evaporating a coating material are ionized to one polarity in plasma.
An ion plating method for accelerating the ions toward an insulated substrate surface by an electric field and depositing the ions as a coating layer on the substrate surface, wherein the charge of the other polarity is charged from a charge emission source provided in the vacuum vessel. By irradiating the substrate surface to charge the substrate surface to another polarity, a potential difference is formed between the ions and the substrate surface, and the electric field generated by the potential difference accelerates the ions toward the substrate surface. An ion plating method characterized in that: 2. An apparatus for evaporating a coating material, an apparatus for ionizing the evaporated coating material particles to one polarity in plasma, and an electric field for accelerating the ions toward an insulating substrate surface in a vacuum vessel. An ion plating apparatus provided with an accelerating electric field generating device for generating, as the accelerating electric field generating device, irradiating the substrate surface with a charge of another polarity to charge the substrate surface to another polarity, An ion plating apparatus comprising: a charge emission source for forming a potential difference between ions and the substrate surface and generating the electric field by the potential difference.