JPS62246897A - Production of diamond-like carbon film - Google Patents

Abstract

PURPOSE:To obtain a hard diamond-like carbon film having high electric resistance by bringing a gaseous mixture composed of an oxygen-contg. compd. contg. O, C and H and diluting gas into reaction and depositing the same on a substrate at a specific temp. CONSTITUTION:The gaseous mixture composed of the oxygen-contg. compd. contg. oxygen, carbon and hydrogen and diluting gas is deposited on the substrate, by which the objective carbon film is obtd. The resultant diamond-like carbon is the film which consists essentially of carbon and has 2,000-7,000kg/mm<2> Vickers hardness and >=10<10>OMEGAcm electric resistance. The oxygen-contg. compd. to be used is preferably supplied in an extremely fine state, more preferably in a gaseous state and the compd. of <=15C is more preferable in terms of ease of handling in particular. A method for converting the gaseous mixture to plasma by a low frequency of <=300kHz, high frequencies of 300kHz-300MHz, or microwaves of 300MHz-1,000GHz or the like is used as a means for bringing the gaseous mixture into reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing a diamond-like carbon film having excellent properties as an insulating material, a protective film, etc.

<Prior Art> Conventionally, attempts have been made to deposit diamond P on a substrate at a temperature of 300° C. or higher through a plasma reaction using a hydrocarbon such as methane as a raw material (Japanese Patent Laid-Open No. 59-3098). Additionally, attempts have been made to create an amorphous or semi-amorphous carbon layer with microcrystals on a substrate by causing a gas phase reaction of hydrocarbons with plasma at a temperature of 100 to 450°C (Japanese Patent Application Laid-Open No. 58-42473).

In these methods, at temperatures below 300°C, the film tends to become amorphous and hard films cannot be obtained, and at temperatures above 300°C, there are problems such as poor adhesion to the substrate and the tendency for black carbon to form as a by-product. there were.

However, when a mixed gas of an oxygen-containing compound containing oxygen, carbon, and hydrogen and a diluent gas such as hydrogen gas is
No attempt has been made to cause the reaction to occur at a temperature of °C.

<Problems to be solved by the invention> The present inventors solved the above problems by using oxygen-containing compounds containing oxygen, carbon, and hydrogen as raw materials, developed a method for producing nine diamonds, and achieved even higher In research on surface modification of molecules, we discovered that a hard diamond-like carbon film was formed at a low temperature of 100 to 300°C when a mixed gas of an oxygen-containing compound and a diluent gas was subjected to a plasma reaction, and we continued to conduct further research. As a result of repeated efforts, we have arrived at the present invention.

Means for Solving the Problems〉 That is, the present invention involves reacting a mixed gas of an oxygen-containing compound containing oxygen, carbon, and hydrogen with a diluent gas, and
This is a method for producing a diamond P-like carbon film, which is characterized by depositing it on a substrate at a temperature of 0°C.

The diamond P-like carbon obtained in the present invention has a Vickers hardness of 2000 to 7000 Jrl/m", an electrical resistance of 10" Ωm or more, and is a film mainly composed of carbon.

The oxygen-containing compound containing oxygen, carbon, and hydrogen used in the present invention may be entrained in a diluent gas or in a reduced pressure state in a cis-form, solid state, or liquid state, and then supplied to the reaction system. It is preferable to supply it in a minute amount, preferably in a gaseous state.

In particular, a compound having 30 or less carbon atoms is preferable, and a compound having 15 or less carbon atoms is more preferable for ease of handling.

These oxygen-containing compounds are compounds containing oxygen, carbon, and hydrogen, but may also contain sulfur, nitrogen, nitrogen, and the like.

Examples of the oxygen-containing compounds of the present invention include ethanol,
Methanol, pro/gnol, butanol, 5ec-i
Chyl alcohol, tert-f-thyl alcohol, pentanol, hexanol, octatool, 4-methyl-2
- Saturated alcohols such as pentanol, adamantanol, 2,3-dimethyl-2-butanol, furfuryl alcohol, cyclohexanol, acetone, acetylacetone, methylpropyl ketone, acetonyl acetone, ethyl methyl ketone, diethyl ketone, Diisodityl ketone, dibutyl ketone, diethyl ketone, 3゜3-
Dimethyl-2-butanone, butyl methyl ketone, methyl isozorobyl ketone, isobutyl methyl ketone, ketones such as cyclohexanone, acetaldehye P, propionaldehye P1 butyraldehyde, formaldehyde r
1 Aldehyde Ps such as propionaldehyde, 2-ethylhexylaldehyde, flobylaldehyde, citric acid, succinic acid, acetic acid, 3.3-p methylglutaric acid, 2-
Ketopropionic acid, hexamalic acid, propionic acid, maleic acid, caproic acid, calzonic acids such as glutaric acid, methyl acetate, ethyl acetate, trimethyl acetate, ethyl formate, ethyl formate, propyl formate, isopropyl formate, trimethyl citrate , triethyl citrate, dimethyl succinate, diethyl succinate, dimethyl oxalate, diethyl oxalate, methyl methacrylate, ethyl methacrylate, trimethyl acetate, methyl 2-ketopropionate, dimethyl fumarate, diethyl fumarate, ethyl blowionate , methyl zolopionate, butyl propionate, propyl acetate, isopropyl acetate, ethyl maleate, methyl maleate,
Esters such as dimethyl malonate, ethyl malonate, methyl malonate, polyhydric alcohols such as triethylene glycol, 2-tetramethylethylene glycol, butanediol, butylene glycol, cyclohexane dimetatool, etc. Alcohols, ester ethers, ester alcohols, ester ketones, ketone alcohols, etc. are included, and unsaturated compounds are also included.

Further, these oxygen-containing compounds are compounds in which the ratio (010) of the number of oxygen atoms to the number of carbon atoms is 1/1 to 1/100, preferably 1/1 to 1/30.

Further, these oxygen-containing compounds and hydrocarbons basically consisting of carbon and hydrogen may be used in combination. In this case, the hydrocarbons to be used may be entrained in a diluent gas or under reduced pressure in a gaseous, liquid, or solid state and supplied to the reaction system, but in an extremely minute state, preferably by sublimation or Those supplied in a gaseous state are preferred. In particular, hydrocarbons having 30 or less carbon atoms are preferable, and hydrocarbons having 15 or less carbon atoms are more preferable for ease of handling.

Hydrogen, argon, helium, etc. are used as the diluent gas in the present invention.

In the present invention, the mixed gas may be any gas in which the oxygen-containing compound is dispersed in the diluent gas in a gaseous, liquid, or solid state, but preferably in a gaseous state.

Also, the concentration of oxygen-containing compounds in the mixed gas is 10-' to 10' f/1 t/It with respect to the diluent gas, and the concentration of oxygen-containing compounds in the mixed gas is 10-' to 10' f/1 t/It. 4
The growth rate is slow below f/It (,10" f/1.
The above is undesirable because amorphous carbon is likely to be produced.

In the present invention, the means for reacting is 300KH2
A method of plasma generation using the following low frequency waves, 300 KII, high frequency waves of ~300 MH2, microwaves of 300 MHz, ~1000 GHz, a photoreaction method using ultraviolet rays, etc. After ionization, 1! An ion beam method is used in which the ion beam is accelerated in a field and collided with the base material.

The base material used in the present invention is polymethaphenylene terephthalamide, polymetaphenyleneiso7talamyl
Polymers made by polymerizing isoamide 1 such as 1 nylon 6 and nylon 66, terephthalic acid, p-hydroxybenzoic acid, p, p-biphenol, polyesters such as polyethylene terephthalate, polyvinyl chloride, polyacrylonitrile, polymethyl methacrylate , polymethyl acrylate, polypenzimine P1, organic polymers such as polyphenylene sulfide and polyoxymethylene, silicon compounds such as quartz, single crystal silicon, silicon nitride, and silicon carbide, inorganic substances such as boron nitride, glass, carbon, and graphite, copper, iron, Metals such as molybdenum, aluminum, titanium, nickel, tin, and tungsten, and oxides such as sapphire, alumina, and zirconia are used. These base materials can be in various shapes such as plate, film, granule, powder, and fiber.

The substrate may be heated with gas, or may be heated with an external or internal heater. The temperature of the base material is 100 to 300°C. At temperatures below 100° C., the material tends to become amorphous, and at temperatures above 300° C., the carbon film deforms, which may necessitate the use of a special base material.

<Examples> The present invention will be described below with reference to Examples, but it goes without saying that the present invention is not limited thereto. □ Example 1 Using the apparatus shown in FIG. 1, a glass plate was used as the base material, and ethanol was used as the oxygen-containing compound.

First, the inside of the reaction chamber (9) was evacuated to around 10-” Torr, and then the glass plate (7) was heated to 25°C using a heater (8).
Flow hydrogen gas at 100 ct/min from the 0 and 1 diluent gas supply source (1) heated to 0°C, and oxygen-containing supply device (2).
Ethanol was supplied at a concentration of 0.2 fifl.

Adjust the gas pressure to I Torr, and use a high frequency oscillator (1o)
A high frequency wave of 13.56 MHz was oscillated with an output of 250 W to generate plasma.

After 1 hour, a thin film with a thickness of 3 μm was formed on the glass plate. The Vickers hardness was 6000#/m''.

When the infrared absorption spectrum was measured, hydroxyl groups and -
No absorption by H2- was observed. Also, x1rA
When the diffraction pattern was measured, a diamond diffraction pattern was confirmed.

Example 2 Using the apparatus shown in FIG. 2, methyl acetate was used as the oxygen-containing compound and titanium was used as the base material.

First, the inside of the reaction chamber (9) was evacuated to around 10-' Torr, and then the substrate (7) was heated to 200°C. Methyl acetate was supplied at a concentration of 1f/2 from the oxygen-containing supply device (2) while argon was flowing from the dilution gas supply source (1), and the gas pressure was adjusted to 0.1 Torr. Electromagnetic coil (20
) while generating a magnetic field with a magnetic flux density of 500 G, an arc discharge is generated by a DC arc power source (13) Ic, and the ions are further ionized by a heating filament and generated by an ion accelerating power source (15) fi in an electric field of soo v. It was accelerated and collided with the substrate to deposit a carbon film.

The Vickers hardness of the carbon film was 5500#/+1111'', and a diamond P diffraction pattern was observed when measuring X-ray diffraction patterns.

Example 3 A test was carried out in the same manner as in Example 1 using methyl acrylate as a raw material and a glass plate as a base material.

The temperature of the substrate is heated to 150℃, and hydrogen gas is heated to 100at.
/win flow, and methyl acrylate was fed at a concentration of 0.15 f/1. The gas pressure was adjusted to 1.5 Torr, and
A high frequency wave was oscillated with an output of 00 W, and plasma was generated for 2 hours.

The hardness of the carbon film was 500Jef/2.

Comparative Example 1 In the same manner as in Example 1, methane was used as a raw material and heated to 200° C. to deposit a carbon film on the base material.

Methane supply rate is 10cc/min, hydrogen 150 ee
/rn xn adjust the gas pressure to I Torr, 20
Plasma was generated for 2 hours by emitting high-frequency waves with an output of 0W.

The Vickers hardness of the produced carbon film was 1000 #/■2. Furthermore, when the infrared absorption spectrum of the carbon film was measured, absorption due to O-H stretching vibration was observed near 2800 cys-', and no diamond P diffraction pattern was observed in X-ray diffraction.

<Effects of the Invention> According to the production method of the present invention, a hard, high electrical resistance diamond P-shaped carbon film can be obtained on various substrates with a wide area,
The obtained carbon film is industrially useful as a protective film or an insulating film.

[Brief explanation of the drawings] Figures 1 and 2 show one of the manufacturing equipment used in this example.
This is an example. 1... Dilution gas supply device, 2... Oxygen-containing compound supply device, 3... Flow meter, 4.觧.../terube, 6...
・Electronic vision, 7... Base material, 8... Heater, 9... Reaction chamber, 10... High frequency generator, 11... Temperature controller, 12... Vacuum pump, 13... Direct current Arc power supply, 14... Electromagnet power supply, 15... Ion acceleration power supply, 16.16'... AC power supply, 17.17'.
...Heating filament, 18...Shutter, 19.
...Gas nozzle, 20...Electromagnetic coil, le, 21...
- Grid, 22... Base material support.

Claims (1)

[Claims] A method for producing a diamond-like carbon film, which comprises reacting a mixed gas of an oxygen-containing compound containing oxygen, carbon, and hydrogen with a diluent gas and depositing it on a substrate at a temperature of 100 to 300°C.