JPS58174569A - Formation of film comprising metal compound - Google Patents

Abstract

PURPOSE:To form a uniform vapor deposition film without irregularity on a large amount of materials, in forming a film of metal nitride on the surface of each material to be treated by a glow discharge chemical vapor deposition method, by rotating a cathode attached with the material to be treated. CONSTITUTION:A freely rotatable cathode 9 is arranged within a vacuum vessel 8 in a glow discharge chemical vapor deposition apparatus and plural materials 4 to be treated are attached to said cathode in a suspended manner. A gas of halide of a metal belonged to the Group 4a, 5a, 6a of the Periodic Table and a mixed gas of hydrogen and nitrogen are introduced into the vessel 8 under pressure of 0.1-10 Torr. In the next step, DC voltage of 200-800V is applied between the cathode 9 and the inner wall of the vessel 8 as an anode to form a film of nitride excellent in corrosion resistance and decorative property such as a TiN film on each material 4 to be treated by glow discharge. At this time, the materials 4 to be treated are rotated along with the cathode 9 to form a uniform vapor deposition film without irregularity as a whole even if a large amount of the materials 4 to be treated are present.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for forming a metal compound film that can form a uniform and beautiful film on a large amount of substrates.

[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, carbide, titanium, etc., which has excellent wear resistance. In this method, the liquid species of the high melting point compound is formed at a temperature of 900 to 1200°C, so there are limitations in that it cannot be applied to substrates that are easily deformed, such as thin or thin objects, or are made of materials with a low melting point. Ta.

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

Therefore, when used as the outside of a wristwatch, etc., a glow discharge space is formed near the base when coated with the above-mentioned metal compound for the purpose of improving wear resistance and adding decorative properties.
A glow discharge chemical vapor deposition method is being considered in which a chemical reaction is caused by discharge energy 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 evacuating to a degree of vacuum, a mixed gas of metal halide, nitrogen, and hydrogen is introduced into the vacuum container 2 from the gas supply port 3 so that the pressure inside the vacuum container 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. . 200 to 8000 between these electrodes
Applying a DC voltage of V and heating the heating plate 7 provided on the back surface of the cathode plate 5, the substrate to be processed is heated to 200 to 1000°C.
, preferably at 400 to 600° C., a glow discharge space is formed near the substrate to be treated, and the mixed gas reacts on the surface of the substrate to form a metal compound film.

However, when the above-mentioned method is applied to a large number of substrates using a large-sized apparatus to form a coating, the coating may be formed depending on the position of the substrate due to non-uniformity of gas flow and temperature distribution within the apparatus. There was a drawback that unevenness occurred.

[Object of the Invention] It is an object of the present invention to provide a method for forming a metal compound' coating that can form a uniform and beautiful decorative coating even on a large number of substrates.

Summary of the Invention] As shown in FIG.
A columnar cathode 9 equipped with a rotation mechanism is arranged in a vacuum container 8 equipped with a rotary mechanism, a plurality of substrates 4 to be treated are suspended from the cathode 9, and the cathode 9 is rotated around its central axis. Cathode 9
A DC flJI of 200 to 8000v is applied to the wall (l pole) of the vacuum vessel 8! When applying voltage to form a discharge space near the substrate to be processed, the inside of the vacuum vessel 8 is heated to 0.1 to 10 To
The method is characterized in that it is filled with a reactive gas containing a gaseous metal compound of rr to form a metal compound coating on the surface of the substrate.

The substrate to be processed is heated, for example, by heating the inside of the vacuum container 8 to 400 to 600° C. by external heating.

The metal compound applicable to the present invention includes [%la.

va, ■a group nitrides, carbides, borides, or combinations thereof, and these [%la
, va and Vla group halides, hydrogen and nitrogen (or ammonia gas instead of nitrogen) are used.

The mixing ratio of these gases is metal 7\logenide:hydrogen:
The molar ratio of nitrogen is preferably 1:12 to 100:1 to 100, preferably 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. The rotation of the cathode may be any method as long as a uniform coating can be obtained regardless of the state of glow discharge, and continuous rotation is better than intermittent rotation. Also, due to the stability of the sample, it is unsuitable to rotate too fast, so 30" or less, preferably 1 or
Otori or lower is better.

In addition, the method of the present invention can form a uniform decorative metal compound coating on a substrate made of any electrically conductive material, such as metals, semiconductors, and conductive ceramics. .

(Embodiments of the invention) Next, examples of the present invention will be described.

Example A prismatic cathode 9 provided in the center of the vacuum vessel 8 is provided with C
25 consisting of an alloy with a composition of 38%, 8β3.8, and the balance N1
After suspending 900 nX25nX4n metal plates as substrates to be processed and reducing the pressure in the vacuum container 8 to 10-'' Torr,
Gas component ratio TiCβ4:N2:N2=l:19:6 (molar ratio) so that the pressure inside the vacuum container 8 is 2 Torr.
A mixed gas of was injected into the vacuum container 8, and in this state, the cathode was continuously rotated at about 10 rpm to rotate the substrate into the container. Next, the wall of the vacuum container 8 is used as an anode, and the
! A DC voltage of 500 V was applied to one of the cells as a cathode for 30 minutes to cause discharge. At this time, I! of the substrate to be processed! 14 to about 55
It was 0°C. As a result, a uniform and beautiful TiN film of 1 μm was formed on each substrate. Note that there was almost no variation in the film thickness.

On the other hand, when processing is performed without rotating the cathode, the film thickness varies by ±0.
A variation of 2 μ- occurred.

[Effects of the Invention] As is clear from the above examples, according to the method of the present invention, uniform coatings without uneven color can be obtained on a large number of substrates.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view schematically showing the equipment used in the conventional method;
FIG. 2 is a sectional view schematically showing the apparatus used in the method of the present invention. 2.8... Vacuum container 4... Substrate to be processed 5.9...
・・Cathode 6・・・・・・・・・・・・Anode (7317) Representative Patent Attorney Kensuke Norichika (and 1 other person): 1 Figure 1 and Figure 393-

Claims (2)

[Claims] (1) A cathode equipped with a rotation mechanism is placed in a vacuum container equipped with a gas supply port and an exhaust port, a plurality of substrates to be processed are placed on this cathode, and the cathode is rotated. !
! A DC voltage of 200 to 8,000 μm is applied to the (II pole) to form a discharge space near the substrate to be processed, and the inside of the vacuum container is filled with a reaction gas containing a gaseous metal compound at 0°1 to 10 Torr. 1. A method for forming a metal compound film, comprising: forming a metal compound film on the surface of a substrate. (2) The rotation of the cathode is continuous rotation.Claim 1
The method for forming a metal compound film as described in .