WO2007116522A1

WO2007116522A1 - Method of removing diamond coating

Info

Publication number: WO2007116522A1
Application number: PCT/JP2006/307588
Authority: WO
Inventors: Jiro Osawa; Hiroyuki Hanyu
Original assignee: Osg Corporation
Priority date: 2006-04-10
Filing date: 2006-04-10
Publication date: 2007-10-18

Abstract

As shown in Fig. 3, diamond coating (30) is irradiated with oxide ion beams to thereby efficiently etch the diamond coating (30) by both of sputtering phenomenon and oxidation in step S2. Thereafter, in step S3, irradiation with argon ion beams is carried out to thereby etch the diamond coating (30) by sputtering phenomenon only. In this etching by ion beams, the diamond coating (30) can be removed more uniformly than in the use of microwave plasma, so that the danger of partial grave erosion of tool base material (20) can be avoided. Further, the tool base material (20) as it is or after minor rework can be reutilized, and there can be attained inexpensive reproduction of diamond coating working tool (12).

Description

Specification

Film removal method of diamond film

Technical field

[0001] The present invention relates to a method for removing a diamond film, and more particularly to a method for removing a diamond film with as little brazing of the main body as possible.

Background art

[0002] In processing tools such as end mills, taps, cutting tools, rolling dies, or semiconductor devices such as semiconductor lasers and semiconductor sensors, the surface of a body such as a tool base is coated with a diamond film to resist wear. There are some which have improved the hardness and surface hardness (see Patent Document 2). And, if the diamond film of such a diamond-coated member is worn or damaged, or if a defective product is generated due to a coating defect or the like at the time of manufacture, the main body of the tool substrate, semiconductor device, etc. For use, it has been proposed to heat the diamond-coated member by microwaves in a reactor of a microwave plasma CVD apparatus and burn off (de-film) the diamond film by oxygen plasma (Patent Document 1) 3).

Patent Document 1: Japanese Examined Patent Publication No. 59-27753

Patent Document 2: Patent No. 2519037

Patent Document 3: Patent No. 3439423

Disclosure of the invention

Problem that invention tries to solve

[0003] On the other hand, in such a film removal method of a diamond film by oxygen plasma, such a body is made of cemented carbide and the like, and erodes to the main body! There was a problem that the body was deformed or the diameter size was reduced. For example, in the case of a long diamond-coated member, the film deposition rate varies because the temperature distribution becomes uneven, and if it is intended to reliably remove all the diamond coatings, the temperature is high and the film deposition rate is fast. In the part, the body is greatly eroded.

[0004] FIG. 5 (a) shows a diamond-coated curving tool 100, which is an example of a diamond-coated member. The figure shows an end mill with the cutting edge omitted, and the tool base material corresponding to the main body is made of cemented carbide, and the diamond coating is applied to the surface of the blade 102 provided with the outer peripheral blade. 104 is coated. The diamond-coated cutting tool 100 has a tool diameter of 10 mm, a length (edge length) of the blade portion 102 which is a processing portion is 30 mm, and a film thickness of the diamond film 104 is about 20 m. Then, when the film deposition of the diamond coating film 104 was performed on such a diamond coated tool 100 under the following film deposition conditions using a microwave plasma CVD apparatus, the obtained tool base material 106 As shown in (b) of FIG. 5, while the reduction amount Δ D of the blade diameter at the blade base portion is about 30 μm, the blade diameter reduction at the tip end portion is

2

The quantity A D was about 180 / z m. In this case, the tip of the diamond coated tool 100

1

The temperature of the part was high, the film removal rate was faster, and the diameter size was greatly reduced. The hatched area in FIG. 5 (a) represents the diamond film 104, and the hatched area in FIG. 5 (b) is the film removal area from which the diamond film 104 is removed. These figures are not necessarily expressed with the correct dimensional ratio, and in particular, the shape of the film removal area in (b) is an extremely large difference in diameter size.

<< Membrane removal condition >>

• Oxygen plasma

• Microwave 2. Okw

, Pressure 5 torr

• Temperature 850 ° C

The present invention has been made against the background described above, and an object of the present invention is to make it possible to remove a diamond coating without brazing the main body of the diamond-coated member as much as possible.

Means to solve the problem

[0006] In order to achieve the above object, the first invention is a method for removing the diamond coating of a diamond-coated member having a diamond coating coated on the surface of the main body, the main force of the diamond covering member, The film is characterized in that the diamond film is removed by applying an ion beam to the film for etching.

According to a second aspect of the present invention, in the method of removing a diamond coating according to the first aspect, the diamond coating is etched by irradiating an ion beam generated using an inert gas as a loading gas. And the step of

According to a third aspect of the present invention, in the method of removing a diamond coating according to the second aspect, (a) irradiating the diamond coating with an ion beam generated by using a chemically active gas for diamond as a working gas. It has a first etching step of etching, and (b) a second etching step of switching the working gas to an inert gas to generate an ion beam and irradiating the diamond film to perform etching. Do.

According to a fourth aspect of the present invention, in the method of removing a diamond coating according to the third aspect, any one of oxygen, hydrogen and nitrogen is used as the working gas in the first etching step. It is characterized by

According to a fifth aspect of the present invention, in the method for removing a diamond film according to any one of the first to fourth inventions, (a) the diamond-coated member is processed by coating the diamond film on at least a processing portion. The tool is characterized in that (b) the main body is a tool base made of cemented carbide.

Effect of the invention

According to the method of removing a diamond film of the first aspect of the present invention, the ion beam is irradiated to the diamond film to etch, thereby mainly removing the main body of the sputtering film and removing the main force of the diamond film. The diamond film can be removed more uniformly than when plasma is used. And since the film can be removed relatively uniformly in this manner, even if the film is completely removed from the diamond film, the influence on the main body is reduced without fear that the main body will be largely corroded. Since the change is suppressed, it becomes possible to reuse the main body as it is or with just a slight modification, and the diamond-coated member can be regenerated inexpensively.

In the second aspect of the invention, since the etching process is performed by irradiating the diamond film with an ion beam generated by using an inert gas as a working gas, the diamond film is removed by the sputtering phenomenon due to the ion irradiation. It will be done. Therefore, although the film removal rate is reduced, the diamond film is more uniformly removed, and while the film is completely removed, it is possible to minimize the shape change and the dimensional change of the main body. . In the third invention, prior to the second etching step in which etching is performed with the ion beam generated using the above inert gas as the working gas, ions generated using the gas chemically active as diamond as the working gas In the first etching step, the diamond coating is removed by chemical reactions such as oxidation and nitridation in addition to sputtering due to ion irradiation since the first etching step is performed by etching with a beam. Therefore, after the diamond film is efficiently removed in the first etching step, the working gas is switched to move to the second etching step, thereby completely removing the film of the diamond film while changing the shape and dimensions of the main body. It is possible to suppress the change and the film removal processing time is shortened. Also, in the first etching step and the second etching step, it is only necessary to basically switch the cooking gas, and therefore, while the diamond-coated member is held in the predetermined etching treatment container, the first etching step and the first etching step are carried out. 2Etching process can be performed continuously.

Brief description of the drawings

FIG. 1 is a schematic configuration view illustrating an example of a diamond film deposition apparatus capable of suitably carrying out the method of the present invention.

[FIG. 2] is a view showing an example of a diamond-coated machining tool in which the diamond coating is removed by the apparatus of FIG. 1, (a) is a front view, (b) is a surface portion of the blade coated with the diamond coating. It is an expanded sectional view.

[FIG. 3] A flow chart for explaining the procedure for removing a diamond film using the diamond film removal apparatus shown in FIG.

[FIG. 4] A diagram for explaining the dimensional change of the tool substrate when the diamond film is removed according to the flow chart of FIG. 3. (a) shows the condition before removal and (b) shows the condition after removal. .

[FIG. 5] A diagram for explaining the dimensional change of the tool substrate when the diamond coating is removed by the conventional method. (A) shows the condition before removing film, (b) shows the condition after removing film.

Explanation of sign

[0015] 12: Diamond coated processing tool (diamond coated member) 20: tool base (main body)

24: Blade part (processed part) 30: Diamond film

Step S2: First etching process Step S3: Second Etching Step

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is suitably applied to, for example, cutting tools such as end mills, drills, taps and cutting tools, or diamond-coated working tools such as rolling dies, but a diamond-coated semiconductor device coated with a diamond coating. It can be applied to film removal of various diamond coated members, etc.

A superhard tool material such as cemented carbide is suitably used as a tool base on which a diamond film is coated. In order to enhance the adhesion, the surface of the tool substrate can be subjected to a predetermined pretreatment such as roughening treatment or provision of another coating as a base. The same applies to the case of a diamond-coated semiconductor device.

[0018] The diamond-coated member can also be applied when other coatings such as TiN, TiCN, TiAIN and the like are provided at least under the diamond coating which is fine if it is coated.

For the coating of the diamond film, a CVD method such as a microwave plasma CVD method, a hot filament CVD method, or a high frequency plasma CVD method is suitably used. For example, if the film thickness of the diamond film is thinner than 5 m, sufficient action such as abrasion resistance can not be obtained, while if it exceeds 25 μm, it is not preferable because the film easily peels off. The range of m is appropriate, and about 8 to 20 μm is desirable.

[0020] The ion beam etching should be performed by relatively moving the ion beam gun emitting the ion beam and the diamond covering member as necessary so that the ion beam is uniformly irradiated to the diamond film. Hoped. The portions other than the coating area of the diamond film to be etched may be masked with a masking agent such as a photoresist.

[0021] The working gas is a source of ions for generating an ion beam, and the working gas is ionized and irradiated to the diamond film. As the inert gas of the second invention, argon, krypton, xenon and radon are preferably used. In addition, oxygen, hydrogen and nitrogen are suitably used as the chemically active gas for diamond used in the first etching step of the third invention as in the fourth invention. In the implementation of the first invention, other working It is also possible to use

In the third aspect of the invention, ion beam etching is performed using an optically active gas in the first etching step, but in the practice of the first and second aspects of the invention, ion beam etching other than ion beam etching is carried out. It is also possible to roughen the diamond coating using a diamond deposition technique followed by ion beam etching using a working gas such as an inert gas. Example

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic block diagram of a diamond film removal apparatus 10 capable of removing a diamond film according to the method of the present invention using an ion beam etching apparatus, and a diamond coated tool 12 is etched by a chuck 14. The rotary table 18 in the processing vessel 16 is disposed concentric with its center line S. The diamond-coated tool 12 corresponds to a diamond-coated member, and the figure shows the case of an end mill. As shown in FIG. 2, the tool base 20 made of cemented carbide is a shank 22. And a blade 24 is provided on the body. The blade portion 24 is provided with an outer peripheral blade 26 and a bottom blade 28 as cutting edges, and the surface of the blade portion 24 is coated with a diamond film 30 by a coating apparatus such as a microwave plasma CVD apparatus. . The film thickness of the diamond film 30 is in the range of 8 to 20 μm, and is about 20 μm in this embodiment.

[0024] FIG. 2 (a) is a front view of the diamond coated tool 12 as seen from the direction perpendicular to the axis, and FIG. 2 (b) is an enlarged view of the surface portion of the blade 24 coated with the diamond coating 30. It is a sectional view. The hatched portion in FIG. 2 (a) represents a diamond film 30, which is disposed on the rotary table 18 with the blade 24 coated with the diamond film 30 facing upward. The diamond-coated processing tool 12 is a second-hand product in which the diamond coating 30 is worn or damaged due to use, or a defective product produced due to a coating defect of the diamond coating 30 at the time of production. For example, it is possible to place a plurality of diamond-coated tools 12 in parallel with the force center line S so that the film removal processing can be performed simultaneously. is there. The tool base 20 corresponds to the main body, and the blade portion 24 corresponds to the cover portion.

The diamond film deposition apparatus 10 of FIG. 1 has a pair of ion beams having an ion source. The diamond film 30 is etched away by the ion beam emitted from the guns 32a, 32b. The working gas supply device 40 is for supplying a working gas (working gas) serving as a source of ions of the ion beam to the ion beam guns 32a and 32b. In this embodiment, two types of oxygen gas and argon gas are switched. The ion beam guns 32a and 32b emit oxygen ion beams and argon ion beams according to the type of working gas. The inside of the etching processing container 16 is decompressed by a vacuum pump 42. In this embodiment, the degree of pressure (Pressure) is set to 0.1 lPa, and the acceleration voltage of ions is 3. OkV. It is. The ion beam guns 32a and 32b also have a distance of about 200 mm to the diamond coated tool 12. The diamond coated tool 12 is applied with a bias of 50 kHz and 500 V by the bias power supply 44. The ion source current is 500 mA at one time.

The rotary table 18 is rotationally driven at a predetermined rotational speed around a center line S by a rotary drive 46 having an electric motor, a reduction gear, etc., and the diamond-coated machining tool 12 is also integrated with the rotary table 18. It is rotated around its axis (rotation) so that the ion beam is irradiated substantially uniformly over the entire circumference of the blade portion 24. In addition, a vertical moving table 48 is disposed above the rotary table 18, and the ion beam guns 32a and 32b are disposed via two axes of irradiation angle adjusting devices 34a and 34b, respectively, and the diamond coating process is performed. The attitude of the ion beam guns 32a and 32b with respect to the fixture 12, that is, the irradiation angle can be adjusted. In the vertical movement table 48, the ion beam guns 32a and 32b are moved closer to and away from the diamond coated processing tool 12 together with the irradiation angle adjusting devices 34a and 34b according to the diameter size and the like of the diamond coated processing tool 12. Is provided.

The vertical moving table 48 is, for example, a shaft of the diamond-coated machining tool 12 fixed to the rotary table 18 in the vertical direction by an axial moving device 50 having a feed screw which is rotationally driven in both forward and reverse directions by an electric motor. It can be moved linearly in a direction parallel to the heart (center line S). The rotary drive unit 46 and the axial movement unit 50 are respectively controlled by an electronic control unit 52 having a microcomputer or the like, and the diamond coated tool 12 is rotationally driven around its axis, and the ion beam gun 32 By moving the a 32 b up and down, the ion beam is irradiated over the entire length of the blade 24 coated with the diamond coating 30. The irradiation time of the ion beam is appropriately determined according to the length dimension of the blade portion 24, the film thickness of the diamond film 30, and the like. A mask agent such as a photoresist is provided as necessary on portions other than the coating region of the diamond film 30, ie, the shank 22, and etching by ion beam is prevented.

Next, a procedure for removing the diamond film 30 by using such a diamond film removal apparatus 10 will be described according to the flowchart of FIG. In step S1 of FIG. 3, after the diamond-coated processing tool 12 is placed on the rotary table 18, the inside of the etching processing container 16 is decompressed to, for example, about 0.1 kPa by the vacuum pump 42. In step S2, the ion beam guns 32a and 32b are moved up and down while rotationally driving the diamond-coated machining tool 12 about the axis by the rotary drive unit 46 and the axial movement unit 50, while oxygen as working gas from the baking gas supply unit 40 An oxygen ion beam is applied to the diamond film 30 for etching by supplying a gas to the ion beam guns 32a, 32b. Oxygen gas is chemically active against diamond, and in addition to the sputtering phenomenon caused by the irradiation of oxygen ions, the diamond film 30 can be efficiently removed by the oxidation reaction, but the diamond film 30 is completely removed. The processing is performed for a predetermined time (for example, about 5 hours) which is previously determined so as to end before. This step S2 is a first etching step.

[0029] An argon ion beam is formed on the diamond film 30 by performing step S3 and switching the working gas supplied from the working gas supply device 40 to the ion beam guns 32a and 32b to oxygen gas and argon gas as well. Irradiate and etch. Since argon gas is an inert gas, it does not cause a chemical reaction with diamond, but removes the diamond film 30 based on the sputtering phenomenon by irradiation of argon ions. As described above, since the diamond film 30 is removed only based on the sputtering phenomenon, although the film deposition rate is slow, it is possible to uniformly remove the film, and the predetermined time (eg, 3) can completely remove the diamond film 30. Process about time). This step S3 is a second etching step. Thus, the series of etching processes is completed, and the tool substrate 20 with the diamond film 30 removed is taken out of the etching vessel 16 and, if necessary, after regrinding the outer peripheral blade 26 and the bottom blade 28. The diamond coating 30 is coated on the blade portion 24 by a coating apparatus such as a microwave plasma CVD apparatus, thereby being regenerated as a diamond coated processing tool 12.

Here, in the present embodiment, etching is performed by irradiating the diamond film 30 with an ion beam, and the sputtering phenomenon is mainly performed, and the force of the diamond film 30 is also removed, so that the microwave plasma is removed. It is possible to uniformly remove the diamond coating 30 compared to the case of using. And since the film can be removed relatively uniformly in this manner, even when the diamond film 30 is completely removed, the influence on the tool substrate 20 that the tool substrate 20 is not likely to be largely corroded is reduced. The small shape change and dimensional change are suppressed, and the tool base 20 can be reused as it is or with only a small amount of handle, and the diamond-coated cover tool 12 can be regenerated inexpensively. it can.

Further, in step S3, since etching is performed by irradiating the diamond film 30 with an argon ion beam generated using argon gas as a working gas, in step S3, the diamond film is formed by sputtering exclusively by irradiation of argon ions. I am afraid that will be removed. Therefore, although the film deposition rate is reduced, the diamond film 30 is uniformly removed, and the shape variation and dimensional change of the tool substrate 20 are minimized while completely removing the diamond film 30. It can be suppressed.

Further, in step S2 performed prior to step S3, oxygen is etched with oxygen ion beam generated using oxygen gas chemically active to diamond as the working gas. In addition to the sputtering phenomenon by ion irradiation, the diamond coating 30 is removed also by the oxidation reaction. Therefore, after the diamond coating 30 is efficiently removed in this step S2, the working gas is switched to shift to the step S3, and etching is performed with an argon ion beam to completely remove the film of the diamond coating 30 while the tool is being removed. It is possible to suppress the shape change and the dimensional change of the base material 20, and the film removal processing time is shortened. Also, in steps S2 and S3, it is only necessary to switch the working gas. While being held within 16, their steps S2 and S3 can be performed sequentially.

Here, as in the case of the diamond-coated cover tool 100 shown in FIG. 5, the film has a tool diameter of 10 mm, a length of the blade 24 (blade length) of 30 mm, and a film of about 20 μm on the blade 24. The thickness of the diamond-coated diamond tool 12 coated with a thick diamond film 30 is subjected to a film removal treatment according to the procedure of FIG. 3 using the above-described diamond film removal apparatus 10 of FIG. Explain the change. The etching time by the oxygen ion beam irradiation in step S2 is 5 hours, and the etching time by the argon ion beam irradiation in step S3 is 3 hours. And, as shown in (b) of FIG. 4, the tool base 20 obtained by the film removing treatment with such ion beam has a reduction amount A D of the blade diameter of the blade base portion of about

2

The reduction amount A D of the blade diameter at the tip end is about 6 m, which is a decrease compared to the conventional method of Fig. 5

1

As the quantities A D and A D both decrease substantially, the difference between their reduction quantities A D and A D

1 2 1 2 also becomes smaller. As a result, regrinding of the peripheral blade 26 or the like when reusing the tool base 20 is unnecessary or significantly reduced, and the cost when reusing the tool base 20 and regenerating the diamond-coated processing tool 12 is reduced. Is reduced. 4 (a) is a schematic view of the diamond-coated machining tool 12 with the outer peripheral blade 26 etc. omitted, as in FIG. 5 (a).

Although the embodiment of the present invention has been described in detail based on the drawings, this is merely an embodiment, and the present invention is an embodiment to which various changes and improvements are added based on the knowledge of those skilled in the art. Can be implemented in

Industrial applicability

According to the method of removing a diamond film of the present invention, the diamond film is mainly removed by sputtering by irradiating the diamond film with an ion beam for etching, so that the main force of the diamond film is also removed. The diamond film can be removed more uniformly than when plasma is used. And since the film can be removed relatively uniformly in this manner, even when the film is completely removed from the diamond film, the effect on the main body which may partially erode the main body partially is reduced, so that the shape change and the size are reduced. The change is suppressed, and the body can be reused as it is or with only a slight hand. That is, the present invention is preferable when the diamond coating of a diamond-coated member such as an end mill, a tap, or a drill is removed and the main body such as tool base material is reused to regenerate the diamond-coated member. Used properly.

Claims

The scope of the claims

[1] A method for removing the diamond coating of a diamond-coated member, wherein the surface is coated with a diamond coating on the surface of the main body,

The diamond film is removed from the main body by etching by irradiating the diamond film with an ion beam.

A method for removing a diamond film, characterized in that

[2] has a step of irradiating the diamond film with an ion beam generated using an inert gas as a working gas to perform etching

The method for removing a diamond film according to claim 1, wherein the diamond film is removed.

[3] A first etching step of irradiating the diamond film with an ion beam generated by using a gas chemically active to diamond as a working gas for etching, and switching the working gas to an inert gas to perform ion etching A second etching step of generating a beam and irradiating the diamond film for etching;

The method according to claim 2, further comprising:

[4] In the first etching step, any one of oxygen, hydrogen, and nitrogen is used as the working gas.

The method for removing a diamond film according to claim 3, characterized in that:

[5] The diamond-coated member is coated with the diamond film at least at the processing portion! / With processing tools,

The body is made of cemented carbide! It is a tool base that beats,

The method for removing a diamond film according to any one of claims 1 to 4, characterized in that: