JP2003147511A - Cr TARGET MATERIAL - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a Cr target material hardly causing the production (scattering) of coarse grains to reduce the sticking of coarse grains in a vacuum arc deposition. SOLUTION: (1) The Cr target material dispersedly contains Cr nitride. (2) In the Cr target material, the mean free path of a Cr phase is <40 μm. (3) In the Cr target material, the mean free path of a Cr phase is <=25 μm. (4) In the Cr target material, the grain diameter of Cr nitride is <30 μm. (5) In the Cr target material, the grain diameter of Cr nitride is <=5 μm. (6) In the Cr target material, the contents of Cr nitride is >=1 mass%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field relating to a Cr target material, and more particularly to a target material whose base material (matrix) is made of Cr or a Cr alloy, and more particularly to vacuum arc vapor deposition. It belongs to the technical field relating to a Cr target material used as a cathode plate in an apparatus.

[0002]

2. Description of the Related Art A vacuum arc vapor deposition apparatus for applying a wear resistant coating to cutting tools, machine parts, electronic parts, optical equipment parts, etc., stores a substrate to be processed in a vacuum chamber and then By applying a negative bias to the base material and performing arc discharge with the cathode plate as the negative electrode (cathode) and the vacuum chamber side as the positive electrode (anode), the ion particles evaporated from the cathode plate are deposited and deposited on the surface of the base material. It is designed to let you. In this type of vacuum arc vapor deposition equipment,
It is required to reduce the number of molten particles having a coarse particle size, which is an unsuitable material for making the density of the coating film deposited and deposited on the surface of the base material highly dense and uniform.

As a technique for responding to this demand, a large number of permanent magnets are provided on the back side of the cathode plate (outside the vacuum chamber) so that the polarities of adjacent permanent magnets are opposite to each other. An attempt was made to achieve the intended purpose by generating a complicated magnetic field (see Japanese Patent Laid-Open No. 8-283933), or a particle passage diameter-reduced portion was provided at an intermediate position from the cathode plate to the substrate. In the above, a ring-shaped electromagnetic coil is provided around this and the lines of magnetic force are converged by this to achieve the intended purpose (Japanese Patent Laid-Open No. 2-1941).
No. 67), or one that mechanically moves a permanent magnet along the surface of the cathode plate (outside the vacuum chamber) (see Japanese Patent Laid-Open No. 64-262), the cathode plate and the base plate. A technique for reducing the adhesion of coarse particles by improving the mechanism of the apparatus, such as one in which a deflection magnetic field is disposed between the material and the coarse particles to be removed (see Japanese Patent Laid-Open No. 2001-3160), has been proposed.

[0004]

In addition to the ionic particles which are preferable for film formation (formation of a film), the generated substances (scattered substances) from the cathode of the evaporation source of the vacuum arc vapor deposition apparatus have, for example, a diameter of about several μm. Or more coarse particles are included. The coarse particles fly to the base material (hereinafter, also referred to as a substrate) and adhere to the surface of the base material, and the coating film (hereinafter, also referred to as a film) is easily peeled off from the vicinity of the coarse particles, and thus the coarse particles are caused. There is a major problem that the adhesion of the film to the substrate is reduced due to the above. Moreover, the adhesion of coarse particles lowers (roughens) the surface roughness of the film, resulting in an increase in the coefficient of friction and a decrease in the sliding characteristics. For example, when it is used for friction sliding parts having a large surface pressure represented by piston rings for engines, further improvement is required.

However, in the conventional technology for reducing the adhesion of coarse particles by improving the mechanism of the device, the device must be changed,
Replacing the device is costly, and in many cases, the productivity is lowered due to the reduction of the film forming rate.

The present invention has been made in view of the above circumstances. Focusing on the target material used as the cathode plate, the generation (scattering) of coarse particles is less likely to occur and the adhesion of coarse particles can be reduced. An object of the present invention is to provide a Cr target material (a target material whose base material is Cr).

[0007]

In order to achieve the above object, the Cr target material according to the present invention comprises:
The Cr target material described in No. 6 is used, which has the following structure.

That is, the Cr target material according to claim 1 contains Cr nitride dispersedly.
It is a target material (first invention).

The Cr target material according to claim 2 is C
The Cr target material according to claim 1, wherein the mean free path of the r phase is less than 40 µm (second invention). The Cr target material according to claim 3 has a Cr phase mean free path of 2
The Cr target material according to claim 1 having a thickness of 5 μm or less (third invention).

The Cr target material according to claim 4 is the Cr target material according to any one of claims 1 to 3, wherein the grain size of Cr nitride is less than 30 μm (fourth invention).
The Cr target material according to claim 5 has a grain size of Cr nitride of 5 μm or less, and C according to any one of claims 1 to 4.
r target material (fifth invention).

The Cr target material according to claim 6 is the Cr target material according to any one of claims 1 to 5, wherein the content of Cr nitride is 1% by mass or more (sixth invention).

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is implemented in the following modes, for example. Powdered Cr and powdered Cr nitride (Cr ₂ N,
After mixing with a Cr nitride such as CrN), this is sintered and molded by powder hot pressing to obtain a Cr target material containing Cr nitride dispersed therein. Then, the Cr target material according to the present invention is obtained. At this time, C
When the mean free path of the r phase is set to be less than 40 μm or 25 μm or less, the Cr target material according to the second or third invention of the present invention can be obtained. Also, Cr nitride
When the grain size is less than 30 μm or 5 μm or less, the Cr target material according to the fourth or fifth invention of the present invention can be obtained. Nitride C with Cr target material
When the content of r is 1 mass% or more, the Cr target material according to the sixth aspect of the present invention can be obtained.

The Cr target material is used as a cathode plate in a vacuum arc vapor deposition apparatus after the sintering and molding or after being further machined.

The present invention is implemented in such a form.

The present inventors have conducted extensive research and studies to achieve the above-mentioned object. Hereinafter, the contents and results, and the effects of the present invention will be described.

The source of coarse particles is a molten pool formed on the surface of the cathode plate. The arc current is always concentrated on the cathode plate surface during film formation, that is, the target surface, and due to the local Joule heating accompanying this current concentration, a molten pool with a diameter of 40 μm or less is formed on the target surface. It is formed. Here, the electron emission point where the arc current is localized on the surface of the cathode plate is called an arc spot. The number of arc spots depends on the magnetic field condition on the surface of the cathode plate, but is usually one or more. Generally, it is qualitatively understood that speeding up the arc spot behavior is effective for reducing coarse particles.

On the other hand, it is generally known that arc spots cannot continue to exist at the same location. This is because the flow of ions emitted from the molten pool competes with the electron current, making it impossible to secure a current path. As a result, the arc spot naturally behaves by wandering around the target surface. However, this natural movement alone produces a large molten pool and a large amount of coarse particles.

It is considered that forcibly moving the arc spot is effective in reducing local overheating. Magnetic field application is a conventional technique as a means for speeding up arc spot behavior. That is, the arc spot behavior is also moved by the interaction with the magnetic field on the surface of the cathode plate. It is generally known that the amount of coarse particles generated can be reduced by increasing the magnetic field on the surface of the cathode plate. It is considered that this is because the interaction with the arc spot is strengthened by the increase in the magnetic field and the moving speed of the arc spot is increased, and as a result, the size of the molten pool is reduced, and the size of coarse particles is further reduced.

The inventors of the present invention pay attention to the fact that the arc spot moving speed varies depending on the cathode plate material, use argon or nitrogen or a mixed gas thereof as the atmosphere gas, and use titanium aluminum alloy, pure titanium, as the cathode plate material. The arc spot behavior when a typical cathode plate material such as pure chromium was used was captured by a high-speed camera, and the arc spot movement speed was quantitatively evaluated. As a result, it was found that the electron emission performance of the cathode plate material and the cathode plate surface product during film formation is closely related to the arc spot behavior, and the arc spot moving speed becomes faster as the material emits electrons more easily.

The inventors of the present invention have made it necessary to reduce the size of the molten pool in order to reduce the generation of coarse particles. To achieve this, the arc spots are dispersed to suppress the concentration of arc current. It was considered effective to do so and to speed up the behavior of the arc spot. Therefore, based on the idea that it is effective to add a material that easily emits electrons, that is, a material having a work function lower than that of the base material, repeated intensive research was conducted. For example, a cathode plate material prepared by adding a material that easily emits electrons such as Cr nitride (Cr nitride such as Cr ₂ N or CrN) to pure chromium was manufactured, and the arc spot behavior was investigated. This arc spot behavior is best investigated in 1 second
A high-speed camera capable of shooting 40,500 frames was used. Pure chromium and pure titanium have work functions of 4.5 eV and
Since it is a material of 4.3 eV, it is difficult to emit electrons. But,
These are materials that easily emit electrons when they become nitrides.

That is, the inventors of the present invention expected that these nitrides would act to promote the movement of the arc spot by embedding the nitrides in the cathode plate. We fabricated and examined the manufacturing conditions of the cathode plate that has the effect of speeding up the arc spot behavior and reducing coarse particles. At this time, the powder hot pressing method was used as the method for producing the cathode plate material containing nitride. The particle size of the powder used is 10 to 75 μm for pure chromium and pure titanium, and 3 for nitrides such as Cr ₂ N and TiN.
˜40 μm. The powders were mixed with a V mill or a pencil mixer and then sintered and molded by a powder hot press.

As a result of this examination, it was found that the Cr target material containing nitrides (additives) such as Cr ₂ N and TiN dispersed therein had an increased arc spot moving speed and a decreased amount of coarse particles. I found it.

Further, at this time, the moving speed of the arc spot and the frequency of generation of coarse particles are related to the particle size and dispersion state of nitrides such as Cr ₂ N and TiN. In order to increase the grain size, it is effective to reduce the grain size of the nitride and enhance the uniform dispersibility. In particular, the grain size of the nitride should be less than 30 μm and / or the mean free path of the Cr phase should be reduced. It was found that setting the particle size to less than 40 μm is effective in reducing the amount of coarse particles generated.

The reason why it is effective in reducing the amount of coarse particles generated will be explained as follows.

In the Cr target, Cr nitride (Cr ₂ N, CrN
In a target in which Cr nitrides such as Cr) are dispersed, the arc spot hops while selecting a portion where Cr nitride grains easily emit electrons. However, if the grain size of Cr nitride exceeds a certain level, the arc spot stay time at the position where Cr nitride exists becomes long. As a result, Cr around Cr nitride is also melted, resulting in an increase in the size of the molten pool, an increase in the amount of particles generated, and an increase in the amount of coarse particles generated. Therefore, in order to increase the degree of reduction in the amount of coarse particles generated, it is desirable that the grain size of Cr nitride be small and the existing form of Cr nitride be a fine structure. Particularly, it is effective that the average grain size of Cr nitride is less than 30 μm.

In a target in which Cr nitride is dispersed, if the dispersibility of Cr nitride is poor and the distance between the Cr nitride particles is long, hopping of the arc spot will not be carried out smoothly (smoothly), and the moving speed of the arc spot will be reduced. And the melt pool size increases. This allows
The frequency of generation of coarse particles increases. Therefore, in order to increase the degree of reduction of the amount of coarse particles generated, it is desirable to reduce the distance between Cr nitride particles. In particular, it is effective that the distance between the Cr nitride particles is less than 40 μm in the mean free path of the Cr phase. The average free path of the Cr phase is obtained as follows. That is, by observing the microstructure, the number N _{L of} Cr nitride particles per unit length hit by an arbitrary straight line on the microscope surface and the number N _S of Cr nitride particles contained in an arbitrary unit area are obtained and used. Volume ratio of Cr nitride f = (8 / 3π) · (N
_L ² / N _S ), and from this, the mean free path λ of the Cr phase
= (1-f) / _NL was calculated.

The present invention has been completed based on the above findings. The invention thus completed relates to a Cr target material, which is claimed in claim 1.
~ 6 Cr target material (Cr target material according to the first invention to the sixth invention).

That is, the Cr target material according to the first aspect of the present invention is a Cr target material characterized by containing Cr nitride dispersed therein. According to this Cr target material, as can be seen from the above-mentioned knowledge, the moving speed of the arc spot increases, the amount of coarse particles generated decreases, the generation (scattering) of coarse particles hardly occurs, and the adhesion of coarse particles can be reduced. become.

The Cr target material according to the second aspect of the present invention is characterized in that the Cr target material according to the first aspect of the present invention has an average free path of the Cr phase of less than 40 μm. According to this Cr target material, as can be seen from the above-mentioned findings, especially the moving speed of the arc spot is increased, the size of the molten pool is reduced, and the degree of reduction of the amount of coarse particles can be further increased. When the average free path of the Cr phase is set to 40 μm or more, the moving speed of the arc spot decreases, and it tends to be difficult to sufficiently increase the degree of reduction of the coarse particle generation amount. From this point of view, it is desirable that the average free path of the Cr phase is less than 40 μm.

The Cr target material according to the third invention of the present invention is specified as having a mean free path of the Cr phase of 25 μm or less in the Cr target material according to the first invention or the second invention. According to this Cr target material, the moving speed of the arc spot is further increased, the size of the molten pool is reduced, and further, the degree of reduction of the amount of coarse particles generated can be further increased. Further, in terms of further increasing the degree of reduction of the amount of coarse particles generated, the mean free path of the Cr phase is preferably 20 μm or less, and more preferably 15 μm or less.

In the Cr target material according to the fourth aspect of the present invention, the grain size of Cr nitride in the Cr target material according to the first aspect, the second aspect or the third aspect is 30.
It is specified to be less than μm. According to this Cr target material, as can be seen from the above-mentioned findings, the arc spot residence time is shortened particularly at the Cr nitride existing position, the molten pool size is reduced, and by extension, the degree of reduction of the amount of coarse particles can be increased. . In addition, when the grain size of Cr nitride is 30 μm or more, the arc spot stay time at the Cr nitride existing position becomes long, the molten pool size becomes large, and by extension, the degree of reduction of the amount of coarse particles is sufficiently increased. Tends to be difficult. From this point of view, the grain size of Cr nitride is preferably less than 30 μm, more preferably 20 μm or less, or even 10 μm.
It is more desirable that the thickness is less than μm.

The Cr target material according to the fifth invention of the present invention is such that the grain size of Cr nitride in the Cr target material according to the first invention, the second invention, the third invention or the fourth invention is 5 μm or less. It has been specified. According to this Cr target material, the arc spot stay time at the Cr nitride existing position is further shortened, the size of the molten pool is reduced, and by extension, the degree of reduction of the amount of coarse particles can be further increased.

The Cr target material according to the sixth invention of the present invention is such that the content of Cr nitride in the Cr target material according to the first invention, the second invention, the third invention or the fourth invention or the fifth invention is 1 mass. % Or more. When the content of Cr nitride is set to 1% by mass or more as described above, it depends on the grain size of Cr nitride,
The mean free path of the phase can be shortened to such an extent that it is effective in reducing the amount of coarse particles generated. When the particle size of Cr nitride is less than 30 μm, the mean free path of the Cr phase is 40%.
It can be less than μm. In addition, nitride C
If the content of r is less than 1% by mass, it tends to be difficult to shorten the mean free path of the Cr phase to the extent that it is effective in reducing the amount of coarse particles generated. From this point of view, the content of Cr nitride is preferably 2.5 mass% or more, more preferably 5 mass% or more, or even 10 mass% or more. However, Cr nitride
If the content of Cr exceeds 30% by mass, the Cr
The amount (% by mass) of Cr decreases and the effective amount of the Cr target material decreases. Further, if the content of Cr nitride exceeds 30 mass%, the cost is increased and the density of the sintered body (Cr target material) is difficult to increase. Therefore, in these points as well, the content may be 30 mass% or less. desirable.

In the present invention, the Cr target material is a target material whose base material (matrix) is made of Cr or a Cr alloy. Cr nitride is a nitride of Cr, and examples thereof include Cr ₂ N and CrN. The Cr phase is a phase made of Cr or a Cr alloy.

The mean free path of the Cr phase is λ = (1-f) / N _L obtained by the method described above. That is, by observing the microstructure, the number N _{L of} Cr nitride particles per unit length hit by an arbitrary straight line on the microscope surface and the number N _S of Cr nitride particles contained in an arbitrary unit area are obtained and used. Volume ratio of Cr nitride f = (8
/ 3π) · (N _L ² / N _S ), and λ = (1−f) / N _L obtained from this.

The grain size of Cr nitride is the average grain size of Cr nitride. Therefore, the grain size of Cr nitride is, for example, 30 μm.
In addition to the case where all of the Cr nitride particles have a particle size of 30 μm, the case where m has a particle size of more than 30 μm and the average value thereof is 30 μm. Also, the fact that the grain size of Cr nitride is less than 30 μm means that
Other than when all r particles are less than 30 μm, 30 μm
The average value is less than 30 μm even if the particle size exceeds the limit.

In producing the Cr target material according to the present invention, the method is not particularly limited, but normally, powder metallurgy using powdery Cr (or Cr alloy) and powdery Cr nitride as raw materials is used. . That is, after mixing powdery Cr (or Cr alloy) and powdery Cr nitride, this is sintered and molded by powder hot pressing to obtain a Cr target material according to the present invention. However, the method is not limited to such a powder metallurgy method, and another method can be adopted. For example, HIP is mentioned, although it is classified into the same powder metallurgy method. It is also possible to obtain the Cr target material according to the present invention by blowing a nitrogen-containing gas such as nitrogen gas or ammonia gas into the molten Cr.

[0038]

EXAMPLES Examples of the present invention and comparative examples will be described below, but the present invention is not limited to these examples.

After mixing powdery Cr and powdery Cr nitride (Cr ₂ N or CrN), this was sintered and molded by powder hot pressing, and thereby, Cr nitride of 100 mm in diameter was contained. A disc-shaped Cr target material was obtained. At this time, the particle size of powdered Cr was changed in the range of 10 to 75 μm, and the particle size of powdered Cr nitride was changed in the range of 3 to 40 μm. Further, the mixing ratio of the powdery Cr and the powdery Cr nitride (that is, the content of Cr nitride in the Cr target material) was changed in the range of 0 to about 11 mass% as a parameter. Table 1 shows the grain size of Cr, the grain size of Cr nitride, and the content of Cr nitride. For powder mixing,
In the case of No. 13, a V mill mixer was used, but in all other cases, a pencil mixer was used.

With respect to the Cr target material thus obtained, measurement of the mean free path of the Cr phase, measurement for confirming the grain size of Cr nitride, and confirmation of the presence and nitridation of Cr nitride in the Cr target material were carried out. The measurement for confirming the Cr content (mass%) was performed by the following method.

Regarding the measurement of the mean free path of the Cr phase,
The method described above was used. That is, by observing the microstructure, the number N _{L of} Cr nitride particles per unit length hit by an arbitrary straight line on the microscope surface and the number N _S of Cr nitride particles contained in an arbitrary unit area are obtained and used. Volume ratio f = (8 / 3π) · (N _L ² / N _S ) of Cr nitride is obtained, and from this, the mean free path λ of the Cr phase is λ = (1−f) /
_NL was determined.

The measurement for confirming the grain size of Cr nitride was performed by the Fulman method. That is, the number N _{L of} Cr nitride particles per unit length hit by an arbitrary straight line on the microscope surface and the length L across the Cr nitride particles in the same unit length are obtained, and the average of the Cr nitride is calculated using these. Particle size =
1.7 × N _L / L was determined.

The powder X-ray method and EPMA were used for the measurement for confirming the presence of Cr nitride in the Cr target material and for confirming the content of Cr nitride. That is, the Cr target material is bromine methanol (bromine 3-1
It was dissolved in a methanol solution containing 0 mass%), and the residue was subjected to X-ray diffraction to confirm the presence of Cr nitride. The content of Cr nitride was confirmed by quantitatively analyzing the amount of nitrogen contained in the residue with EPMA.

Results of these measurements [Measurement result of mean free path of Cr phase, measurement result of Cr nitride (Cr ₂ N or CrN) particle size, and content of Cr nitride in Cr target material (% by mass) ) Measurement results] are shown in Table 1. That is, as a result of these measurements, it was confirmed that the Cr nitride particle size and the Cr nitride content (mass%) were the same as the values shown in Table 1 above. The mean free path of the Cr phase was the value shown in Table 1.

The above Cr target material was used as a cathode plate in a vacuum arc vapor deposition apparatus, and the pressure was 20 mm Tor.
WC with a surface roughness of 0.05 μm or less in a nitrogen atmosphere of r
AIP film formation for forming a Cr nitride film having an average film thickness of 5 μm was carried out using a cemented carbide chip as a base material. At this time, the arc current during film formation was 150A. A permanent magnet is arranged on the back surface of the cathode plate, and the arc spot rotates in the plane of the cathode plate by the magnetic field generated by this magnet. Average moving speed of the arc spot (angular speed)
Was obtained by analyzing the image of the high speed camera.
Table 1 shows the average angular velocities of the arc spots.

The surface roughness Ra of the film after the film formation was measured using a contact type surface roughness meter (Surfcom 120A Ver.2.1A). The results are shown in Table 1. It should be noted that the larger the amount of generated coarse particles, the larger the amount of attached coarse particles, and thus the surface roughness of the film becomes worse (rougher) and Ra increases. Therefore, the surface roughness Ra of the film is equal to the amount of attached coarse particles or Further, it can serve as an index of the amount of coarse particles generated, and means that the smaller the surface roughness Ra of the film, the smaller the amount of coarse particles generated and the smaller the amount of coarse particles attached.

As can be seen from Table 1, the Cr target material in the case of code No. 1 is a Cr target material that does not contain Cr nitride or the like, whereas the Cr target materials in the case of code Nos. 2 to 20 are It is a Cr target material containing Cr nitride (Cr ₂ N or CrN) dispersed therein. Compared to No. 1, in No. 2 to 20, the average moving speed (angular velocity) of the arc spot is higher, and the speed of the arc spot behavior, which is effective in reducing the amount of coarse particles, is increased. Has been realized.

As can be seen from these Nos. 2 to 20, particularly Nos. 8 to 11, the smaller the mean free path of the Cr phase, the smaller the surface roughness Ra of the film, and the smaller the mean free path of the Cr phase is. It is shown to be effective in reducing the amount of coarse particles generated. In particular, when the average free path of the Cr phase is less than 40 μm, the surface roughness Ra of the film is small, which is effective in reducing the amount of coarse particles. Further, comparing Nos. 2 to 20, it is found that the surface roughness Ra of the film becomes smaller when the average free path of the Cr phase is 25 μm or less (see especially No. 13). Furthermore, when the mean free path of the Cr phase is 20 μm or less,
Further, when it is 15 μm or less, it is suggested that the surface roughness Ra of the film becomes smaller in this order (in particular, 15 μm).
Refer to No.12 for the following and No.14 for 20 μm or less).

As can be seen from Nos. 2 to 20, especially Nos. 4 to 7, the smaller the grain size of Cr nitride, the smaller the surface roughness Ra of the film. It is shown to be effective in reducing the amount generated. In particular, it can be seen that when the grain size of Cr nitride is less than 30 μm, the surface roughness Ra of the film is small, which is effective in reducing the amount of coarse particles generated. Further, comparing Nos. 2 to 20, when the grain size of Cr nitride is less than 30 μm, 20 μm or less, and further 10 μm or less, the surface roughness Ra of the film becomes smaller in this order. It is suggested (see especially No. 6). Further, it can be seen that when the grain size of Cr nitride is 5 μm or less, the surface roughness Ra of the film becomes smaller (see especially No. 7).

In Nos. 12 and 14 to 17, the grain size of Cr nitride is 3 .mu.m, and the content of Cr nitride is used as a parameter in the range of 1.3 to 9.9 mass%. As can be seen from Nos. 12 and 14 to 17, the smaller the content of Cr nitride, the larger the mean free path of the Cr phase and the larger the surface roughness Ra of the film. When the content of Cr nitride is 1.3% by mass, which is the minimum content, the degree of improvement in the surface roughness Ra of the film due to the inclusion of Cr nitride is small. Although it is not shown in Table 1 when the content of Cr nitride is less than 1% by mass, it is considered that the degree of improvement of the surface roughness Ra of the film by the inclusion of Cr nitride is extremely small. It can be said that these facts indicate that the content of Cr nitride is preferably 1% by mass or more.

In the case of No. 13, powder mixing was carried out by V mill mixing, and in the case of No. 12, powder mixing was carried out by a pencil mixer. The contents are almost the same.
As you can see from No.13 and No.12, No.13 is No.1
Compared with the case of 2, the average free path of the Cr phase is large, and the surface roughness Ra of the film is large. this is,
This is because in the case of V-mill mixing, the dispersibility of the powder is worse than in the case of mixing with a pencil mixer. This indicates that it is desirable to uniformly disperse the Cr nitride during mixing, which allows a smaller mean free path of the Cr phase.

As can be seen from Table 1, there seems to be an influence of the grain size of Cr, but this does not mean that the grain size of Cr itself directly affects the surface roughness Ra of the film, but powder metallurgy. Since the Cr target material is manufactured by the method,
It is considered that the grain size of Cr indirectly affected the surface roughness Ra of the film. That is, since the Cr target material is manufactured by the powder metallurgy method, the distance between the Cr nitride particles is less likely to be smaller than the particle diameter of Cr, and the larger the particle diameter of Cr is, the larger the distance between the Cr nitride particles is. It is considered that the larger the grain size of Cr, the larger the mean free path of the Cr phase (see Table 1), and as a result, the larger the surface roughness Ra of the film.

[0053]

[Table 1]

[0054]

According to the Cr target material of the present invention, the moving speed of the arc spot is increased, the amount of coarse particles generated is reduced, and the generation (scattering) of coarse particles is less likely to occur, thus reducing the adhesion of coarse particles. You will be able to get rid of it.

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Claims (6)

[Claims] 1. A Cr target material containing Cr nitride dispersed therein. 2. The Cr target material according to claim 1, wherein the mean free path of the Cr phase is less than 40 μm. 3. The Cr target material according to claim 1, wherein the Cr phase has an average free path of 25 μm or less. 4. The Cr target material according to claim 1, wherein the grain size of Cr nitride is less than 30 μm. 5. The Cr target material according to claim 1, wherein the grain size of Cr nitride is 5 μm or less. 6. The Cr target material according to claim 1, wherein the content of Cr nitride is 1% by mass or more.