JPS58174568A - Formation of film of metal compound - Google Patents

Abstract

PURPOSE:To prevent the stoppage of vapor deposition reaction due to arc discharge in a cathode introducing pipe part, in coating the surface of a material to be treated with metal nitride according to a glow discharge chemical vapor deposition method, by cooling the cathode introducing pipe part of an apparatus. CONSTITUTION:A cathode 5 and an anode 6 are opposedly arranged within a vacuum container 2 in a glow discharge chemical vapor deposition apparatus while a material 4 to be treated made of a metal or ceramics is placed on the cathode 5 to be heated to 400-600 deg.C by a heating plate 7. After the vacuum container 2 is evacuated from an exhaust port 1, gaseous metal halide and a mixed gas of hydrogen and nitrogen are introduced into said container 2 from a gas supply port 3 under pressure of 0.1-10 Torr and DC voltage of 200-800V is applied between both electrodes to form by vapor deposition by glow discharge a film excellent in corrosion resistance and decorative property such as a TiN film on the surface of the material 4 to be treated. At this time, a cathode introducing pipe 8 is cooled to 200 deg.C or less by water cooling with a cooling pipe and the generation of arc discharge in the introducing pipe 8 is prevented to prevent the stoppage of vapor deposition reaction due to arc discharge.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for forming a film of a metal compound such as titanium nitride that has excellent wear resistance and decorative properties, and more specifically, a method for forming a film of a metal compound such as titanium nitride that has excellent wear resistance and decorative properties. Regarding how to prevent the occurrence.

[Technical background of the invention and its problems] Conventionally, on the surface of a substrate made of metal, ceramics, etc.
Chemical vapor deposition is known as a method for forming a film of a high melting point compound such as titanium nitride or titanium carbide, which has excellent wear resistance. In this method, the coating of the high-melting point compound is formed at a temperature of 900 to 1200°C, so there is a limitation that it cannot be applied to substrates that are thin or thin, easily deformed, or made of materials with a low melting point. .

Another disadvantage is that the surface of the resulting coating is rough, making it unsuitable for decorative purposes.

For this reason, when used as the outside of a wristwatch, etc., a glow discharge space is formed near the base when coating with the above-mentioned metal compound in order to improve wear resistance and add decorative properties. A glow discharge chemical vapor deposition method is being considered in which a reaction is caused and the heating temperature required for coating is as low as 400 to 600°C.

This method will be explained with reference to FIG. 1 when, for example, the surface of a substrate is coated with metal nitride. First, the inside of the vacuum chamber 2 is evacuated from the exhaust port 1 connected to the vacuum pump to a pressure of 10'Torr or less. After the vacuum chamber is evacuated to a degree of vacancy, a mixed gas of metal halide, nitrogen, and hydrogen is introduced into the vacuum chamber 2 through the gas supply port 3 so that the pressure inside the vacuum chamber 2 is 0.1 to 10 Torr. Disposed within the vacuum chamber 2 are a cathode plate 5 that is installed in an electrically conductive state with the substrate 4 to be processed, and an anode plate 6 that is supported above the cathode plate 5 at a predetermined interval. There is. The distance between these electrodes is 200 to 8000
By applying a DC voltage of V and heating the heating plate 7 provided on the back surface of the cathode plate 5 to bring the temperature of the substrate to 200 to 1000°C, preferably 400 to 600°C, the temperature near the substrate to be processed is heated. A glow discharge space is formed and a metal nitride coating is formed.

However, in this method, since the cathode introduction tube 8 is close to the heating plate 7, the groove formed on the anode side of the cathode plate 5 extends beyond the edge of the cathode to the cathode introduction tube 8 side. The problem is that the discharge reaches the bottom (anode) of the vacuum vessel 2 as shown by the arrow, and the main discharge begins to occur in this area, eventually transitioning to arc discharge and hindering the formation of a film on the substrate surface. was there.

[Object of the invention] The present invention solves the above-mentioned problems, and the present invention solves the above-mentioned problems.
It is an object of the present invention to provide a method for preventing the formation of a metal compound film on a surface and preventing the occurrence of an arc discharge phenomenon.

[Key Points of the Invention] That is, the present invention is characterized in that the outer wall of the cathode introduction t18 is cooled.

Second! ! 1 schematically shows an apparatus used in the method of the present invention, in which a cooling pipe 9 made of copper or the like is arranged in a spiral shape within a cathode introduction tube 8. Cooling is performed by liquid (for example, water) or gas (for example, cooling air) flowing within the cooling pipe 9.

In the apparatus configured in this manner, the outer wall of the cathode introduction tube 8 is cooled, so that no metal compound coating is formed. Note that the temperature of the cooled introduction pipe surface is 200°C.
Hereinafter, it is desirable to keep the temperature preferably below 100°C.

The metal compounds applicable to the present invention include ■a, Va
, q'la group nitrides, carbides, borides, or combinations thereof, and these rVa
, Va, Via group halides, hydrogen and nitrogen (
Or use ammonia gas instead of nitrogen. The mixing ratio of these gases is such that the molar ratio of metal to hydrogen: hydrogen: nitrogen is from 1:12 to 100:1 to 100, preferably from 1:12 to 50:1 to 30. The reason for this is that if it deviates from this value, it is difficult to obtain a uniform decorative film.

Furthermore, the method of the present invention can be applied to any electrically conductive material in addition to metals, semiconductors, conductive ceramics, etc.

[Embodiments of the invention] Next, an example will be described.

Example: On the bottom plate in a vacuum container equipped with a gas supply port and an exhaust port,
A processing device was used in which a cathode plate was placed on the top, a cathode introduction tube with a cooling pipe was installed inside, and an anode plate was placed opposite the cathode plate.
A metal plate of 25n x 25n x 4u made of an alloy with a composition of Ni remaining was placed on the cathode plate as a substrate to be treated, and the treatment was carried out under the following conditions. As a result, no TiN film was formed on the surface of the cathode introduction tube. The reaction was smooth. The TiN coating on the obtained substrate was uniform and glossy.

Reaction gas composition Ticbus:N2:N2-1;1
16 (molar ratio) Pressure 2T0rr Voltage
500v Current density 0.11A/CI Substrate temperature 550°C Processing time 30 minutes On the other hand, a processing device without a built-in cooling pipe in the cathode introduction tube was used, and the rest of the processing was carried out in the same manner as in the example.
During the process, the TiN film was not formed on the substrate, but was formed downward from the top of the cathode introduction tube surface, so the process was stopped.

[Effects of the Invention] As is clear from the above examples, according to the method of the present invention, a metal compound film is not formed on the surface of the cathode introduction tube, so there is no risk of an arc discharge phenomenon occurring. ,
A metal compound film can be smoothly formed on the substrate surface.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view schematically showing a processing apparatus used in the conventional method, and FIG. 2 is a schematic sectional view of the processing apparatus used in the method of the present invention. 2......Vacuum container 4......Substrate to be processed 5...
......Cathode plate 6...Anode plate 7...Heating plate 8...・Cathode introduction tube 9...
・・・・・・Cooling pipe (7317) Representative patent attorney Kensuke Norichika (and 1 other person) 1

Claims (2)

[Claims] (1) A cathode introduction tube with a cathode body placed on the top is placed upright on the bottom plate of a vacuum container equipped with a gas supply port and an exhaust port, and an anode body is placed facing the cathode body, A substrate to be processed is placed on the cathode body and the inside of the vacuum container is evacuated, and then a reaction gas containing a gaseous metal compound of 0.1 to 10 Torr is introduced, and a voltage of 200 to 8000 V is applied between the two electrodes.
A metal compound characterized in that the outer wall of the cathode introduction tube is cooled in forming a film of a metal compound by a reaction product on the surface of the substrate by applying a voltage of Method for forming compound film. (2) The method for forming a metal compound film according to claim 1, wherein the cooling is performed by a cooling vibe provided in the cathode introduction tube.