JPS6196721A - Film forming method - Google Patents

Abstract

PURPOSE:To form a hard film having strong adhesive force with the surface of a substrate at a high deposition speed by a method wherein an ion plating method and an ion mixing method are conjointly used. CONSTITUTION:A film forming substance is coated on the surface of a substrate using an ion plating method, and non-metallic ions are implanted simultaneously or alternately on the above-mentioned film. To be more precise, when non-metallic ions are made to irradiate on the surface of the film while the formation of said film on the substrate surface is started using an ion-plating method and the film is grown in the range of thickness with which the effect of ion mixing can be obtained, the adhesive strength between the substrate and the film is strengthened and the film is firmly adhered to the substrate. Subsequently, when the desired film forming substance is deposited on the film by performing an ion plating method, the desired film can be formed on said film at a high deposition speed.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a method of forming a film on the surface of a substrate, and more particularly, to a method of forming a film that can form a hard film with high adhesion to the substrate in a short time. .

[Technical background of the invention and its problems] In recent years, so-called coated tools such as cutting tools and wear-resistant tools in which the surfaces of various substrates are coated with a film of hard substances such as metal nitrides and metal oxides have rapidly become popular. ing.

This film forming method can be broadly classified into chemical vapor deposition method and physical vapor deposition method.

The ion blating method, which is one of these methods, is widely applied because it has practical advantages such as being able to obtain a high-quality film and having a high film formation rate.

However, the coating formed by the ion spray swing method does not have sufficient adhesion to the substrate.

In applications such as cutting tools where a large external mechanical force is applied to the coating itself, a phenomenon occurs in which the coating 9 peels off from the base.

Various measures have been proposed to increase the adhesion of the film to the substrate, one of which is known as an ion mixing method. This method is.

This is a method in which a film of a certain substance is previously formed on the surface of a substrate, and non-metal ions such as ionized diluted scum are irradiated onto the film at a predetermined ion acceleration energy.

In this case, the atoms constituting the film recoil due to collision with the irradiated ions and penetrate into the interior of the substrate, resulting in 2! Forms a new layer with the atoms of the body. Therefore, according to this method, the substrate and the coating achieve strong adhesion through the above-described new layer.

However, in the case of this ion mixing method, the irradiated ions do not themselves form a new film;
It merely enables the ion mixing effect between the substrate and the already existing coating, and the magnitude of the ion mixing effect varies depending on the type of irradiated ions, acceleration energy, and type of substrate. Since this effect occurs at a depth of about 0.05 to 0.1 JLI6 from the irradiation point, this effect does not occur at the interface between the coating and the substrate when the IRM is too thick, and the irradiated ions are wasted inside the coating. It is consumed further and does not contribute to improving the adhesion between the two.

[Purpose of the Invention J] The present invention uses the ion blating method and the ion mixing effect in combination to simultaneously bring out the advantages of both methods, thereby forming a hard film with high adhesion to the substrate surface at a high deposition rate. The purpose of the present invention is to provide a novel film forming method that makes it possible to do this.

[Summary of the Invention] As a result of extensive research aimed at achieving the above object, the present inventors have discovered that after starting to form a film on the surface of a substrate using the ion blating method, the thickness of the film falls within the range within which the ion mixing effect can be achieved. If the surface of the coating is irradiated with non-metal ions while it grows, the adhesion between the substrate and the coating will be strengthened, and the coating will firmly "root" on the substrate, so to speak. The inventors came up with the idea that the desired film could be formed at a high deposition rate if the desired film-forming substance was deposited by ion blasting, and the method of the present invention was developed.

That is, the method of the present invention is characterized in that when a film-forming substance is deposited on the surface of a substrate by an ion-blating method, nonmetallic ions are implanted into the film simultaneously or alternately.

In the uninvented method, first, the substrate may be made of any material such as ceramics, Mi hard alloy, cermet, or various metals or alloys, and the material itself does not matter, but the substrate itself constitutes the negative electrode in the ion blating method. For this reason, it is preferable that the substrate be an electrical conductor. However, even if the substrate is an electrical insulator, a thin film of an electrical conductor may be formed on the surface by a conventional method.

The film-forming substance to be deposited on the surface of the substrate may be appropriately selected depending on the purpose of use, but specifically, carbides and nitrides of metals in groups rVa, Va, and Via of the periodic table, Examples include borides, oxides, sulfides, or mutual solid solutions thereof; silicon carbides and nitrides; aluminum nitrides, borides, oxides, and diboron carbides and nitrides.

Each of these may be formed as a single film, or may be formed as a composite film formed by appropriately mixing two or more of these substances, or furthermore, a film of each substance alone may be formed in multiple layers. It may be formed as a laminated film formed by laminating layers.

The method of the present invention will be explained in detail using the apparatus illustrated in the figure. 6 First, 1 is a reaction chamber in which a film is formed on the surface of a substrate.

The inside of the reaction chamber 1 is maintained at a predetermined pressure with a gas containing one of the constituent substances of the film to be formed.For example, when the film to be formed is a carbide, nitride, boride, acetide, or sulfide. Hydrocarbons such as methane and acetylene, nitrogen-containing gases such as nitrogen and ammonia, boron-containing gases such as volatile pollane, oxygen, and oxygen-containing gases such as water, respectively.

A sulfur-containing gas such as hydrogen sulfide is supplied to each
form an enclosure. 2 is the gas supply source for this purpose. The pressure inside the reactor 1 varies depending on the ion blating method used, but is usually 10-2 to 10-' T.
It is about orr. 3 is an exhaust system.

4 is a port that accommodates the other constituent material of the film to be formed. The other constituent material here refers to Ti when the film to be formed is TiN, TiG, etc. In other words, according to the above-mentioned specific example, it is a member of the rVa, Va, and Vra groups of the periodic table. is a metallic element.

In addition, metalloids such as arsenic, heptimony, bismuth, silicon, germanium, boron, and aluminum can also be used. Alternatively, they may be mutually liquid.

Reference numeral 5 denotes an electron gun for irradiating nine electron beams 5a onto the other constituent material mentioned above, and functions as a heating means. Resistance heating means or high frequency heating means can also be applied.

Reference numeral 6 denotes a high-frequency coil used in the high-frequency ion brating method, and is designed to be connected to a high-frequency power source 7 and to form a blow discharge within the coil region. Reference numeral 8 is a high-voltage direct power supply, with port 5 serving as an anode and base 9 serving as a negative pole. At this time, the negative applied voltage to the base is 1 to 5K.
V is preferable, and 6 may be any electrode, filament, etc. as long as it is easily ionized.

When the high-frequency coil and electron gun are activated while maintaining a predetermined atmosphere and pressure in the reaction chamber l, a predetermined metal, for example, evaporates from the port and becomes ionized, and furthermore, in the process of passing through the glow discharge region, the atmosphere It causes a chemical reaction with gas and becomes a film-forming substance that adheres to the substrate surface.

In the method of the present invention, non-metal ions are irradiated at the same time that the film-forming substance is deposited on the substrate surface or alternately with a slight time lag.

The non-metal ions may be any ion species that has a predetermined ion acceleration energy and that exhibits an ion mixing effect at the interface between the substrate 9 and the formed coating, for example, Boron ion (B“)
, carbon ion (Cゝ), sulfur ion (Sa, nitrogen atom ion (N4), nitrogen molecular ion (N2ゝ), oxygen atom ion (0°), m elementary molecular ion (02"), helium ion (He") ), argon ion (Ar”),
Types of these nonmetallic ions include krypton ions (Kr) and neon ions (Ne'').
It is appropriately selected depending on the relationship with the intended film-forming substance.

At this time, the ion acceleration energy of these nonmetal ions to be irradiated is within the range of 2 to 100 KeV, particularly 5 to 9
It is preferable to set the energy to 0 KeV. If this energy is smaller than 2 KeV, the ion mixing effect will not proceed effectively and the sputtering phenomenon will become dominant on the surface of the film, causing the ion to be formed or to be formed. The coating is “
It is difficult to achieve your desired goal because you are always trying to lose weight, and
If it exceeds oOKeV, a large amount of lattice defects will occur in the film, making it impossible to obtain a good quality film.

Such non-metal ions are irradiated onto the coating on the surface of the substrate from the ion generator 10 attached to the reaction chamber l shown in the figure.The gas is ionized in the figure and introduced into the ion source 10b through the leak valve lOa. After being ionized here, it is accelerated by the accelerations rj and lOc to provide a predetermined ion acceleration energy. The ions are then placed in the analysis magnet lo
d, and only the necessary ion species are magnetically selected and supplied from, for example, a converging lens 10e in the direction of the arrow in the figure to irradiate the coating formed on the substrate 9.

In the method of the present invention, this nonmetal ion irradiation is performed.

In the former case, it is carried out at the same time as depositing the film-forming substance on the substrate surface, or immediately after the film is formed.
The ion mixing effect is expressed at the moment of film formation, and the film growth progresses in a state of strong adhesion, and in the latter case, the ion mixing effect is also exerted.

Even after the coating is formed with strong adhesion, if ion irradiation is continued or interrupted, the desired film will be formed at a high deposition rate by the ion plating method.

Furthermore, in order to further laminate another film on top of this film, the above operation may be repeated.

[Embodiments of the Invention] Example 1 Using the illustrated apparatus, four people supplied nitrogen gas from the gas supply source 2 into the reaction chamber 1, and the inside of the chamber 1 was filled! The pressure was maintained at 0.04 Torr. A P30 chip was used as the substrate 9 and a negative voltage of 3 KV was applied to it. In addition, 13.56M is added to the high frequency coil 6.
A power of Hz was applied.

Nitrogen gas is introduced into the ion source 10b from the leak pulse loa, and the generated ions are accelerated by the accelerator 10c to 50K.
An acceleration energy of eV was applied. These ions were introduced into an analytical magnet, and only nitrogen molecular ions (N2+) were magnetically selected.

First, the output s from the electron gun 5 is applied to the titanium metal in the port 4.
An oow electron beam was generated and irradiated onto metal titanium, causing the titanium metal to explode.

At the same time, the substrate 9 was irradiated with nitrogen molecular ions from a converging lens lOe at an irradiation density of 1016 ions/Cm2 for 10 minutes. A titanium nitride (Tie) film was formed on the surface of the substrate. Part 11! The cumulative velocity is 0.05 h m/-1n
Met.

Next, while the TiN film was irradiated with nitrogen molecular ions, the output of the electron gun 5 was increased to 2 KW and titanium was irradiated for 10 minutes. As a result, the formation of TiN11 with a thickness of 2.5 gm was confirmed. Deposition rate 0.
25 pm/win.

For the obtained TiN-coated chip, Ti
The wear resistance of the N coating and the peeling resistance of the coating were investigated. For comparison, similar measurements were also performed on chips on which a film of the same thickness was formed using only the ion blating method.

Wear resistance test: Chips were set into slices, cutting speed 148m/l1il, depth of cut 2■, feed rate 0.2
5US304 stainless steel was milled for 2 passes for 6 minutes under the condition of 2 m1/rotation, and the average wear width and maximum wear width at that time were measured.

Peeling resistance test: Set the chip on a cutting tool, cutting speed 30m/win, depth of cut 1.5■, feed rate 0.3
948G carbon steel was wet-cut under the condition of 5 mm/rotation, and the peeling width of the coating was measured.

The above results are summarized in the table.

Example 2 First, TiN with a thickness of about 0.05 tm was prepared in the same manner as in Example 1 except that the nonmetal ions were argon ions.
A film was formed.

Then, while continuing to irradiate with argon ions, the output of the electron gun 5 was increased to 3 KW to irradiate titanium for 15 minutes. As a result, a TiN film having a thickness of about 5 wafers was formed.

Deposition rate: 0.33 voices 1 minute.

Then, while continuing to irradiate argon ions, the reaction chamber 1
The interior was replaced with an atmosphere with an oxygen partial pressure of 10''5 Torr, and the aluminum in the separately placed port was ignited for 10 minutes using a 500W electron beam. , 03 coatings were formed.

The wear resistance and peeling resistance of the obtained chip were almost the same as those of Example 1.

[Effects of the Invention] As is clear from the above explanation, according to the method of the present invention, the formed coating exhibits an ion mixing effect at the interface with the substrate, so the adhesion between the two is large and the coating is This solves the peeling problem. Since the subsequent deposition rate of the film-forming substance is controlled by the ion-blating method, the film-forming speed is very high, and the resulting film is of good quality, reflecting the characteristics of the ion-blating method.

Therefore, if the method of the present invention is applied to the substrates of various cutting tools, tools having hard coatings with excellent wear resistance and peeling resistance can be manufactured with high productivity, resulting in their industrial value. is extremely large.

[Brief explanation of the drawing]

The figure is a conceptual diagram showing an example of an apparatus suitable for applying the method of the present invention.

Claims (2)

[Claims] (1) A method for forming a film, which comprises depositing a film-forming substance on the surface of a substrate by an ion-blating method and simultaneously or alternately implanting nonmetallic ions into the film. (2) The film forming method according to claim 1, wherein the ion acceleration energy during the non-metal ion implantation is from 5 KeV to 90 KeV.