JPH01168857A - Formation of titanium nitride film - Google Patents

Abstract

PURPOSE:To form the title TiN film contg. Ti2N crystal and having excellent adhesive strength and hardness by specifying the Ti vapor-deposition rate, accelerating voltage for N, and N input in the formation of the hard TiN film on the surface of a steel member by vacuum deposition. CONSTITUTION:The inside of a vacuum vessel 11 is evacuated from an exhaust port 10, and gaseous N is supplied at a low pressure from a gas inlet 8. The gaseous N2 particle is formed into positive ion by an electron shower from an electron radiation source 7, and the ion is accelerated by the accelerating voltage 6 impressed with a negative voltage of 1-80kV and projected on a substrate 1 to be treated. The Ti in a crucible 4 is heated by an electron-beam gun 3, vaporized, and deposited on the substrate 1. In this case, the Ti vapor deposition rate is controlled to 0.1-200Angstrom /sec and the irradiation amt. of N ion to 1X10<12>-1X10<15> ion/mm<2>.sec, the ions consisting of 20-100% gaseous N2 and 0-80% inert gas are clustered, and the cluster is projected on the substrate.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a method for forming a hard titanium nitride film with strong adhesion on sliding members, tool surfaces, etc. that are subjected to large rubbing forces. .

[Conventional technology]

Figure 2 is a schematic diagram of the ion brating method shown in, for example, Metal Surface Technology Vol. 30, No. 5, pp. 232-240 (1979). , (2) is a substrate support stand, (5) is a titanium material,
(8) is the gas inlet, (9) is the DC power source for acceleration, α@ is the exhaust system, G11 is the vacuum device that collects each member, Ta is the high frequency coil, αJ is the power supply to the high frequency coil ■, G4 is the filament for evaporation, and US is the power supply applied to the filament L.) Next, we will explain the operation.First, make the inside of each vacuum device vacuum, and then introduce nitrogen gas from the gas inlet port (8). death,
The high frequency coil (12+) and the board (1
) A high-frequency electric field is generated by generating a high-frequency discharge between the two. Electricity is applied to the filament α from the filament power supply αS to heat and evaporate the titanium material (5). These evaporated titanium particles enter the high-frequency electric field, and some of them collide with ionized or excited nitrogen particles and electrons.
It is ionized and reacts with nitrogen particles to form "'cTiN".
It becomes a particle. These particles are accelerated by the negative potential of the substrate (1) and adhere to the surface of the substrate (1).

[Problem that the invention seeks to solve]

In conventional methods, the controllability of the composition, texture, and crystal structure of the film was low, and the resulting film did not have sufficient hardness. In addition, since most of the particles are not ionized, the collision energy with the substrate is low, and the adhesion of the film is weak, resulting in problems such as the formed film peeling off from the substrate.5 This invention solves the following problems. [Means for solving the problem] The method for forming a titanium nitride film of the present invention is to obtain a method for forming a hard titanium nitride film with strong adhesive force. , titanium is vapor-deposited onto the workpiece in vacuum at a rate of 0.1-200λ/Sec, and at the same time, ions containing nitrogen are accelerated at an acceleration voltage of 1-80KV onto the workpiece being irradiated with irradiation II
X 10"-I X I Q" 1ons/mmL
It is implanted for 20 seconds to form a film containing TiN crystals.

[For production]

In this invention, it is possible to control the composition, texture, and crystal structure of the film by taking advantage of the fact that the deposition rate of titanium and the implantation area of nitrogen ions can be individually controlled, and that the accelerating voltage of nitrogen ions can be changed. Therefore, it is possible to synthesize Ti2N crystals in TiN crystals, or to synthesize only Ti2N crystals.
Nitrogen ions implanted into the surface of the substrate (that is, the workpiece) collide with titanium atoms flying onto the substrate surface at the same time as they are implanted into the substrate at the initial stage of film formation.

When titanium atoms are pushed into the substrate, internal diffusion is promoted by the recoil effect of nitrogen ions and internally generated defects, and the titanium atoms are introduced into the substrate. In this way, mixing occurs near the boundary between the substrate and the formed film,
A layer containing a mixture of implanted nitrogen atoms, deposited titanium atoms, and substrate atoms is formed, and a film is formed while the composition changes in a coupled manner. By forming a boundary layer with a smooth concentration gradient in this manner, the adhesion force of the film to the substrate can be greatly increased.

〔Example〕

An embodiment of the method for forming a titanium nitride film according to the present invention will be described below with reference to figures. Figure 5m1 is a cross-sectional configuration diagram of a film forming apparatus for carrying out the method for forming a titanium nitride film according to the present invention. 11, +21, +51 and (8)~U
is the same or equivalent part to the conventional device shown in Fig. 2. (3) is an EB (El!ec) for heating titanium material (5).
tion Beam) Gun, (4+ Haruri, (61
is an ion accelerating electrode, and (7) is an electron radiation source for ionizing nitrogen gas.

The method for forming a titanium nitride film using the apparatus described above will be briefly explained. First, vacuum 8 units (10'ror inside Ill)
After evacuation to the order of R, nitrogen gas was introduced from the gas inlet (8) to a pressure of the order of IQ-4 Torr, and the nitrogen gas particles were showered with electrons from the electron radiation source (7). After the nitrogen gas particles are positively ionized, they are accelerated by applying a negative voltage to the accelerating electrode (6) and irradiated onto the 1 substrate + 11 ff surface.

At this time, the titanium material (51) suspended in the crucible (4) is heated and evaporated using an EB gun (3) and deposited on the surface of the first substrate.1. At the same time, for example, the rapid deposition of titanium is performed at 3 QA/sec, and the irradiation amount of nitrogen ions is 1.2
When the acceleration voltage of nitrogen ions is 30 KV, the titanium nitride film formed on the surface of the workpiece is composed of TiN crystal and Ti,
The ratio with N crystal is TiN:Ti, N = 4
: A film with a Vickers hardness of 6 was obtained, and the Vickers hardness Hy-=2
At 200 tons or more, no peeling phenomenon was observed even under severe conditions. At this time, the titanium deposition rate was 0.
1 to 200 A/sec, the irradiation amount of g-ion (which can be controlled by adjusting the electron radiation source (7)) is l x l
01” ~l X I Q151ons/ramlse
c. The appropriate acceleration voltage for nitrogen ions is about 1 to 80 KV.

By changing the film forming conditions within this range, the ratio of 1' i N crystal to T i 2 N crystal in the t film can be controlled. If the titanium deposition rate is lower than IA/sec, the processing rate will be slow, it will have little industrial significance, and the proportion of impurities will increase. The titanium deposition rate is 200A/sec.
If t is less, it is necessary to increase the area for ion implantation, excessive temperature rise of the substrate (workpiece) occurs, and a large-scale ion source is required, which are disadvantageous. tx nitrogen ion irradiation amount
If the irradiation amount is less than txt, the processing speed will be slow and nitrogen will not enter sufficiently, resulting in the formation of a film with a large amount of titanium.
If the temperature is higher than 0.05 m, the substrate temperature will become too high, which will impair the shape accuracy of the substrate, and the adhesion of the film will decrease as thermal diffusion progresses, which is undesirable. If the acceleration voltage is set to 80 KV or higher, the substrate temperature becomes too high, impairing the shape accuracy of the substrate, and as thermal diffusion progresses, the film's adhesion force decreases. This will lead to a decrease in
Preferably, the deposition rate of titanium is set to l at the beginning of the film.
, by suppressing the QA/sec to a low value and ensuring a sufficient mixing area for nitrogen and titanium atoms and substrate atoms.
After that, when the film thickness is 600 to 800 At, the deposition rate is gradually increased to form a boundary layer with a smooth concentration gradient and to obtain extremely high adhesion between the film and the substrate. It becomes possible.

In addition, although the example shows the case where 100% nitrogen gas is used as the ionization gas, the same effect can be obtained by using a mixed gas of 50% nitrogen and 50% inert gas such as argon. It will be done. The ratio of nitrogen and inert gas is preferably nitrogen:inert gas=20-100%+SO~0≠.

It is also good to mix nitrogen with a reactive gas such as hydrogen, and the mixing ratio is nitrogen: reactive gas = 20-100 chi: 80~
θ% is preferred.

For vapor deposition of titanium, a vacuum vapor deposition method, a sputter vapor deposition method, a method using an ion gun for cluster ionizing titanium, or the like may be used.

〔Effect of the invention〕

f: As explained above, the method for forming a titanium rat film of the present invention involves applying titanium to a workpiece in a vacuum at a concentration of 0.1 to 200%.
At the same time, ions containing nitrogen are deposited on the workpiece being deposited at an accelerating voltage of 1 to 80 Kv.
Accelerate with
Since the implantation is performed at a rate of s/mm2-sec to form a film containing TizN crystals, it is possible to form a very hard titanium nitride film and to obtain a film that has extremely strong adhesion to the workpiece. can be formed.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional configuration diagram of a film forming apparatus used in the method of forming a titanium nitride film of the present invention, and Fig. 2 is a cross-sectional configuration diagram of a conventional film forming apparatus. EB gun & (4j crucible, (5) is a titanium material, (6) is an accelerating electrode, (7) is an electron radiation source, (8) is a gas inlet, and l is a vacuum gas outlet. In the figure, The same symbols indicate the same or equivalent parts.Masuo OiwaFigure 1

Claims (5)

[Claims] (1) Apply titanium to the workpiece in vacuum with a thickness of 0.1 to 200 Å/
At the same time, ions containing nitrogen are accelerated on the workpiece being vapor-deposited at an acceleration voltage of 1 to 80 KV, and the irradiation amount is 1 x 10^1^2 to 1 x 10^1^5 ions.
A method for forming a titanium nitride film in which implantation is performed at a rate of s/mm^2·sec to form a film containing Ti_2N crystals. (2) A film containing Ti_2N crystal is composed of TiN crystal and Ti_2N crystal.
A method for forming a titanium nitride film according to claim 1, which is a film containing 2N crystals. (3) The method for forming a titanium nitride film according to claim 1 or 2, in which either a vacuum evaporation method or a sputter evaporation method is used for vapor deposition of titanium. (4) Claim 1 or 2 uses an ion gun that cluster ionizes titanium for vapor deposition of titanium.
A method for forming a titanium nitride film as described in . (5) Nitriding according to any one of claims 1 to 4, using a gas containing 20 to 100% nitrogen and 0 to 80% inert gas or reactive gas as ions. Method of forming titanium film.