JPH04297569A - Method and apparatus for forming film - Google Patents

Abstract

PURPOSE:To avoid mixture of impurity and to form high purity film in film forming method by using ion inplantation together with vacuum vapor-deposition. CONSTITUTION:A shutter 5 arranged just in front of a material 9 to be treated is closed, and vapor-deposited film 8 is formed beforehand on part irradiated with ion beam in a treating chamber 1 and after that, the material 9 to be treated is irradiated with the ion beam to form the vapor-deposit film. In this way, as the film coating treatment is executed after coating absorbing gas and contamination in inner wall of the treating chamber, such a absorbing gas, etc., is not released during the film-coating treatment, and development and mixture of impurity is prevented.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a film having excellent wear resistance and corrosion resistance on the surface layer of a material by using a combination of ion implantation and vacuum deposition.

0002

2. Description of the Related Art In a conventional film forming apparatus that uses both ion implantation and vacuum evaporation, a shutter is provided immediately before the ion source, vapor deposition source, etc., and no shutter is provided in front of the material to be processed. The purpose of these is to prevent the ion source from irradiating the material to be processed until the plasma within the ion source is stabilized and the ion beam can be stably extracted, and for the evaporation source to This was to prevent the substance from adhering to the material to be treated until it was heated and melted within the hearth and stable vapor deposition was obtained. When the ion beam and vapor deposition became stable, both shutters were opened and film formation started.

[0003] The procedure for a film forming method using a combination of ion implantation and vacuum evaporation is to first set the processing chamber at atmospheric pressure, attach the material to be processed, and evacuate the chamber.After reaching a predetermined degree of vacuum, ion implantation and vacuum evaporation are performed. A film is formed using vacuum evaporation, and once the treatment is finished, the pressure is returned to atmospheric pressure and the material to be treated is replaced. At this time, the inner surface of the processing chamber and the sample holder are exposed to the atmosphere each time the material to be processed is replaced, so that adsorbed gases such as oxygen and moisture in the atmosphere and contamination adhere to the inner surface of the processing chamber and the sample holder.

[0004] During film formation, in order to perform ion beam irradiation, adhering gases, contaminants, etc. are re-released into the processing chamber by ion beam sputtering. A large amount of this is released especially in the initial stage of film formation. This released adsorbed gas and contamination are taken into the film during film formation, causing a decrease in the purity of the film.

In order to avoid this, when replacing the material to be processed, dry nitrogen or inert gas is introduced into the processing chamber to return it to atmospheric pressure, and these gases are flowed into the processing chamber to remove as much atmospheric gas as possible. Although it is common practice to replace the gas to prevent it from entering, this method is not sufficient to prevent the gas from entering, and there are further problems such as the danger of oxygen deficiency for workers and the high operating costs. In addition, great care had to be taken to avoid contamination during replacement work.

[0006]

[Problems to be Solved by the Invention] An object of the present invention is to prevent adsorbed gases and contaminants adhering to a processing chamber from being released during film formation in a thin film forming method that uses both ion implantation and vacuum evaporation. , provides a method and apparatus for forming a highly pure film.

[0007]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention is designed to solve the problems described above, since it is inevitable that atoms are emitted by sputtering caused by irradiation with an ion beam. By pre-depositing the same material on the parts to be irradiated other than the treated material, adsorbed gases and contamination are prevented from being released. That is, since this pre-deposited film is made of the same material as the subsequently deposited film, even if it is released into the processing chamber by ion beam sputtering, it does not affect the purity of the film. Therefore, the gist of the present invention is to form a thin film in a method of forming a thin film using a combination of ion implantation and vacuum deposition, in which a vapor deposited film is formed in advance on a portion of the material other than the material to be irradiated with the ion beam, and then the material to be processed is irradiated with the ion beam. The purpose is to form a highly pure film by irradiating the film.

[0008]

[Operation] The contents of the present invention will be explained based on the drawings. FIG. 1 shows an outline of the device configuration. A sample holder 2, an ion source 3, and a vapor deposition source 4 are installed in a processing chamber 1. The material to be processed 9 is attached to the sample holder 2, and vacuum evacuation is performed. When a predetermined degree of vacuum is reached, processing is started, but at this time the sample holder shutter 5 is kept closed (state shown). First, start the vapor deposition source 4,
When the vapor deposition becomes stable, the vapor deposition shutter 6 is opened (moved to the position of the virtual line), and vacuum vapor deposition is performed from the vapor deposition source 4. The thickness of the film formed by vapor deposition at this time varies depending on the thickness of the film to be formed on the material to be treated afterwards. In other words, when the thickness of the film to be formed is large, it is necessary to perform long-term pre-evaporation to receive long-term ion irradiation to make the deposited film thick, and when the thickness of the film to be formed is small, a short-time A thin vapor deposited film is formed by pre-evaporation. The time of this pre-deposition is
After that, the film forming time is set to be half to three times the time required for the combined use of ion implantation and vacuum evaporation. The reason for this is that if the pre-deposited film is too thin, the film will be completely scraped away by sputtering during film formation, and the adsorbed gases and contaminants will be released, so at least half of the film formation time is required. In addition, if too much evaporation is performed, the evaporation material will be wasted, so at most 30% of the deposition time is required.
Approximately twice that amount is appropriate. After this vapor deposition is completed, the ion source 3 is started, and when the ion beam becomes stable, the sample holder shutter drive device 7 provided on the sample holder 2 is driven to rotate the shaft to which the sample holder shutter 5 is attached around the axis. As a result, the sample holder shutter 5 is opened (moved to the imaginary line position), and a film is formed on the surface of the material to be processed 9 by a combination of ion implantation and vacuum deposition. Further, after the vapor deposition prior to film formation is completed, the material to be processed may be cleaned by irradiating only an ion beam as a pretreatment for film formation. At this time, the vapor deposition source 4 is temporarily stopped and the sample holder shutter 5 is opened to perform cleaning.

[0009]

[Example] Titanium nitride films were formed on iron substrates using a conventional method and a method according to the present invention, and were analyzed and compared using glow discharge spectroscopy. The deposition conditions for titanium nitride are: nitrogen ion acceleration voltage: 20 kV, beam current density: 0.44 mA/cm.
2. Titanium deposition rate: 5.0A/s. , film thickness: 1 micron. In the conventional method, after the material to be treated was replaced and the degree of vacuum reached 5×10 −6 torr, titanium nitride film was directly formed. On the other hand, in this method, after replacing the material to be treated and after the degree of vacuum reaches 5 x 10-6 torr, the sample holder shutter is closed before forming the titanium nitride film, and the evaporation rate is 5.0 A/ s. After pre-evaporating titanium, a titanium nitride film was formed. Figure 2 shows the glow discharge analysis results for both films. As can be seen from FIG. 2, the method of the present invention (FIG. 2(a)) captured much less carbon and oxygen than the conventional method (FIG. 2(b)).

0010

[Effects of the Invention] According to the present invention, the material to be treated can be replaced without being affected by atmospheric gases, so dry nitrogen or inert gas is introduced into the processing chamber to return it to atmospheric pressure, and High-purity thin films can be easily formed without the need for complicated work such as replacing the material to be processed or careful handling while keeping gases flowing into the processing chamber while preventing atmospheric gases from entering as much as possible.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of the configuration of a film forming apparatus according to the present invention.

FIG. 2 is a diagram showing the analysis results of a titanium nitride film formed by glow discharge spectroscopy, in which (a) shows the case where the film was formed by the method of the present invention, and (b) shows the case where the film was formed by the conventional method.

[Explanation of symbols]

1...Processing chamber 2...Sample holder 3...Ion source 4... Vapor deposition source 5...Sample holder shutter 6...Vapor deposition source shutter 7...Sample holder shutter drive device 8...Vapor deposited film 9...Material to be treated

Claims (3)

[Claims] 1. A method for forming a thin film using a combination of ion implantation and vacuum deposition, in which, before forming a film on a material to be treated, a vapor deposited film is formed on a portion to be irradiated with an ion beam, excluding the material to be treated, A thin film forming method characterized by forming a highly pure film by subsequently forming a film on a material to be treated. 2. The method according to claim 1, wherein the time required to form the vacuum-deposited film on the part to be irradiated with the ion beam, excluding the material to be treated, is half to three times the time required for subsequent film formation. thin film formation method. 3. A thin film forming apparatus that uses ion implantation and vacuum evaporation in combination, wherein the evaporation source that generates vapor and the sample holder that holds the material to be processed each operate independently, and independently perform the evaporation on the material to be processed. A thin film forming apparatus characterized by being provided with a shutter that can be controlled.