JP3871491B2 - Method for producing multi-element coated thin film - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for forming a thin film by coating a multi-element ultrafine ion granule on the surface of a micro router (Router) using the principles of low temperature PVD (Physical Vapor Deposition), ion cleaning, and ion coating, In particular, the present invention relates to a method for producing a multi-element-coated thin film in which a multi-element of zirconium (Zr), hafnium (Hf), carbon (C), and nitrogen (N) is coated on a micro router.
[0002]
[Prior art]
Micro routers are usually installed on lathes and used for cutting printed circuit board (PCB) materials to perform automated cutting operations. Factories that operate modernized lathes are required to increase production capacity. Furthermore, these factories want to improve their production capacity without increasing the mechanical equipment because of the high cost. In the micro router industry for PCBs, there is a strong demand for micro routers that have high cutting performance, hardness, and wear resistance, and that have a long lifetime. Therefore, by forming a thin film with high adhesion on the micro router, the hardness is increased. It is trying to withstand high-speed rotation and increase the cutting speed to improve production efficiency.
[0003]
However, a method for forming a thin film with high adhesion on a micro router has not been developed so far. The present inventors examined a method of coating a microrouter with a multielement thin film of ultrafine ion granules.
[0004]
A method of forming a thin film such as TiN or TiCN on a covering such as a large router such as tungsten carbide by using the PVD method is well known. Thus, although the hardness and cutting performance of the tool can be improved and the service life can be extended, a method for forming a thin film having high adhesion on a micro router has not been developed. In the conventional thin film forming process, the coating is first cleaned in the atmosphere, and then a film is formed on the coating in a vacuum environment. However, in forming a thin film, the ions ejected from the target are not miniaturized using an ion assisting device, or any other treatment for miniaturizing the ions is not performed. In the subsequent step of thin film formation, the coating is naturally cooled at room temperature.
[0005]
Since the coating is cooled in the atmosphere, the surface of the coating is easily contaminated with oxides. For this reason, when a thin film is formed by the conventional PVD method, the granules of the adhering substance become large and the adhesive force is low. Further, even after a thin film is formed on the coating, the surface hardness is not sufficiently high and the internal rigidity is also low. Furthermore, there is little improvement in wear resistance, and the service life of the coating cannot be extended significantly. Furthermore, what is important is that a thin film having high adhesion cannot be formed on a micro router.
[0006]
Since the conventional CVP (Chemical Vapor Deposition) method is mostly processed at a high temperature of 950 degrees, the rigidity and hardness of the coating is lowered, and is not suitable for forming a thin film on a micro router.
[0007]
[Problems to be solved by the invention]
The present invention has been made in view of these circumstances, and an object thereof is to provide a method of forming a multi-element thin film called ZrxHfxCxNx on the surface of a micro router. In addition, the present invention has a small adhesion substance granule and high adhesion force, so that the thin film does not fall off until the router breaks, the manufacturing time is short, and the router formed with the thin film has a hard surface and internal rigidity. It is an object of the present invention to provide a method for producing a multi-element coated thin film that is high in wear resistance, greatly improved in heat dissipation, excellent in heat dissipation, unchanged in appearance size, and extended in service life.
[0008]
[Means for Solving the Problems]
Therefore, in the present invention, the micro router is cleaned with an electron beam in the atmosphere by the low temperature PVD method, and then heated under vacuum to clean the surface of the micro router with ions. Further, a thin film is formed at a low temperature. Cations are launched with an arc source (ARC Source) device, and only ions with relatively small granules (clusters) are selected through a filter. Further, cations are refined with an ion assist device. Element material covering the micro-router granule (clusters) is small, adhesion is high. For this reason, the router after thin film formation has the advantages of a hard surface and high internal rigidity, cutting speed, wear resistance, cutting accuracy and deformation rate can be improved, and the service life can be extended. . At the same time, the manufacturing period is shortened, and the conventional PVD method and CVP method can overcome the router problem in which a thin film with high adhesion can not be formed on a micro router.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The embodiment of the present invention shows a method of forming a multi-element film of ZrxHfxCxNx on a micro router using the principles of low temperature PVD, ion cleaning, and ion coating. The diameter of the micro router is 0.2-3.175mm, and the material is tungsten carbide alloy or Cermet. According to the present invention, when a ZrHfCN multi-element is coated on a micro router, a thin film of 3 to 4 μm is formed, and the router formed with the thin film has an advantage of high surface hardness and high internal rigidity.
[0010]
In the embodiment of the present invention, the thin film formation method (see FIG. 1) is performed as follows.
[0011]
a. Put the covering on the fixture and, under normal conditions, clean and dry with an electron beam.
[0012]
b. The fixture is mounted in a vacuum furnace and is heated to 120 to 380 degrees in a vacuum state.
[0013]
c. Ion is ejected using an ion device to clean the surface of the coating. This ion device can be an ion source.
[0014]
d. Thin film creation:
(i) A small ion is launched from a target using an arc source. Further miniaturization is performed with an ion source.
[0015]
(ii) Filtration between the target and the coating using a metal filter, allowing only small ions to pass and removing large ions. The filter is isolated by insulating ceramic, prevents the formation of electrodes and favors the passage of minute ions. The micro ions are again further miniaturized with an ion source and coated on the coating.
[0016]
e.C2H2 gas passage
f. Attach the coating (microrouter) to the conical fixture 7 (see FIG. 1) before forming the cooling film in nitrogen. Embodiments of the present invention use a conical fixture 7 to overcome the effect of attractive forces in the vacuum furnace on the material. Before the thin film is formed, the surface of the micro router and even the filth inside the router are cleaned with an electron beam at room temperature and normal pressure, and the micro router is thoroughly cleaned. After cleaning and drying, the tool is placed in a vacuum furnace along with the fixture. Vacuum the vacuum furnace and start heating. After reaching a certain temperature, ions are ejected onto the surface of the coating using an ion cleaning device to remove dirt and oxide on the surface of the coating. This oxide is generated in contact with the atmosphere after washing the coating. The coating surface is thoroughly clean, free of contaminants and can provide good adhesion conditions.
[0017]
After ion cleaning, the thin film preparation work begins. This operation is performed under vacuum and low temperature. Metal ions are ejected from the target with an arc ion facility (Fig. 1). Since ions emitted by the arc source contain relatively large molecular granules, the present invention further refines the metal ions with an ion assisting device to further reduce the granules. The minute metal ions launched by the arc source are assisted by the ion assist device and further reduced by the ion source. At this time, the metal ions become 1/20 of the ions launched by the arc source. By making the ions smaller and more easily attached, it becomes easy to form a multi-element thin film that is hard to break together with other necessary element ions. The film layer has a smooth surface, high hardness, good adhesion, and high density. For this reason, ion assistance is indispensable.
[0018]
In addition, as shown in FIG. 2, a filter 13 having a void size that differs depending on the size of the coating is installed between the target (cation outlet) and the coating, and the ions are filtered to form metal ions (cations) 11. It reduces the speed and provides sufficient time for the ion assist device to separate the metal ions 11. Small ions are allowed to pass through, and large ions are removed by the filter 13 and adhere to the microrouter, resulting in similar ultra-fine granules, and thus can adhere to the coating tightly. Thus, the smoothness of the coating surface can be maintained and the cutting performance can be enhanced. The filter is usually made of a metal material, and the metal filter is insulated by an insulator such as ceramic, so that the filter does not form electrodes and micro ions can easily pass through the filter and be coated on the coating. The The film forming temperature is 120 to 380 ° C., which belongs to the treatment at a relatively low temperature. Since the present invention includes processing steps such as ion cleaning and ion assist, it can be performed at a low temperature. Therefore, it is possible to obtain twice or more hardness after coating without reducing the rigidity of the router. The thin film has excellent adhesion and wear resistance.
[0019]
In addition to rotating the covering in the revolving direction 9, the conical fixture 7 needs to rotate the covering also in the rotation direction 8. More importantly, at the time of design, the revolution and rotation direction must be either clockwise or counterclockwise. In this way, the thickness of the router blade and spine coding can be freely controlled.
[0020]
In the subsequent process of the thin film, rapid cooling is performed under nitrogen, so that there is no influence on the adhesion of the coating, the purpose of high surface hardness and internal rigidity can be achieved, and the process time can be shortened. According to the manufacturing process of the present invention, the thin film preparation operation can be completed in 2 to 2.5 hours, which is shorter than the conventional method. In addition, the granules of the substance adhering to the router surface are small, the surface is smooth, and the adhesion is high. These are the advantages of the present invention. Usually, the thickness of the thin film is 3-4 μm, and does not affect the external size of the router.
[0021]
Currently, the most popular microelectronic router materials are very hard metal alloys such as WC (tungsten carbide), Co (cobalt), TaC (tantalum carbide), TiC (titanium carbide). Cermets containing TiC as the main component and WC, TiN (titanium nitride), TaC, and Co added have better heat resistance and breakage resistance than other alloys. The micro router used in the present invention is made of tungsten carbide alloy and cermet. Since the coating layer is only 3-4 μm, all cutting properties cannot depend on the coating layer alone, and the material properties of these cermets also have a great influence on the performance of the router. After understanding the characteristics of all the coatings, the best microrouter can be obtained only by selecting the target element of the coating according to the characteristics. In the present invention, since the material of the router (micro router) is a tungsten carbide alloy and cermet, an alloy material of Zr and Hf of the same family as titanium is used for the target.
[0022]
The thin film forming method provided by the embodiment of the present invention can be applied with various materials. The following examples further illustrate the invention but do not limit the spirit and scope of the invention.
[0023]
Example 1
The covering is a micro router and the material is cermet. Diameter 1.5mm, effective blade length 8mm. This is called a Cosmos micro router. In the production method of the present invention, the target is a Zr / Hf alloy, and the thin film formation temperature is 120 to 380 ° C.
[0024]
The elemental analysis results after the thin film were: Zirconium Zr 65wt%, Hafnium 15wt%, Carbon 8wt%, Nitrogen 12wt%. This coated router is called a coated cosmos micro router. The thickness of the thin film is 3-4 μm. The hardness of the coated cosmos micro router is more than twice that of the material, and the wear resistance has been greatly improved. Heat dissipation and appearance size have not changed. The service life is extended. This improved the production capacity of the lathe and reduced the production cost of the router.
[0025]
[Micro router measurement report]
Usually, a microrouter is used on a lathe and there are three important parameters.
[0026]
1. Rotation speed: Router rotation speed that indicates cutting speed.
[0027]
2. Forward speed: The forward speed of the router that indicates the amount of cutting.
[0028]
3. Service life: The maximum usage of the router, usually indicated by the amount cut before the blade breaks.
[0029]
Test samples were prepared by coating a U-brand microrouter sold in the market with the method of the present invention, an uncoated product, and a cosmos microrouter coated with the method of the present invention and an uncoated product. The micro router has a diameter of 1.5mm and an effective blade length of 8mm. The micro-router uses “Tachidake (Hitachi shaft)” LS-3B and LS-4B as test equipment, FR (Glass Fiber Rubber) -4 cutting plate (thickness 1.6mm, size 16 × 18, manufactured by Nanya Plastic Co., Ltd.) ) Measured the best conditions of each micro router and compared with other work efficiency and life. The results are as follows.
[0030]
1. Unbranded U brand micro router:
The service life is 20 to 40m under the conditions of rotational speed 28-30krpm and forward speed 14-16mm / s.
[0031]
2. U brand micro router covering:
The service life is 60 to 80m under the conditions of rotational speed of 28 to 32krpm and forward speed of 18 to 22mm / s.
[0032]
3. Uncoated cosmos micro router:
The service life is 40-60m under conditions of rotation speed 28-30krpm and forward speed 16-20mm / s.
[0033]
4. U brand micro router covering:
The service life is 80 to 100 m under the conditions of a rotation speed of 30 to 34 krpm and a forward speed of 24 to 32 mm / s.
[0034]
【The invention's effect】
As described above, the method for forming a thin film by the low temperature PVD method provided by the present invention has the following advantages.
[0035]
1. Coating at low temperature: The PVD thin film forming method of the present invention is processed at a relatively low temperature (120 to 380 ° C), so it avoids the decrease in deposit rigidity due to high temperature, and the hardness of the router after coating is It can be improved more than twice, and the adhesion and wear resistance can also be increased. In such a situation, when it is further coated with other various elements, its adhesion is further improved, and even under normal conditions, the phenomenon of falling off due to the influence of the atmosphere is not observed.
[0036]
2. Use of ion assistance: The minute ions launched by the arc source can be further processed with the aid of the ion source. The obtained ions are 1/20 of those obtained from the arc source. By further miniaturizing the ions, they can be easily attached, and at the same time, can easily coexist with other element ions necessary for coating, forming a hard multi-element thin film, the surface is smooth, high hardness, and adherence. Excellent and high density.
[0037]
3. Heat dissipation: Since the present invention directs heat to the lower end of the coating to dissipate it (that is, it does not dissipate heat at the cutting function), the tip of the router becomes the heat dissipation point, and thermal stress is applied to the coating material. Thus, it is possible to avoid the occurrence of a dropout phenomenon of the thin film due to poor adhesion at the tip of the coating.
[0038]
4. Use of electron beam cleaning: Before forming a thin film, it is possible to clean the router thoroughly by using a physical electron beam under normal conditions to clean the router surface and also the dirt inside the router.
[0039]
5. Wide range of application: When the material of the deposit or the shape of the router is different, special conditions are required, so care must be taken when creating the thin film. If the material of the deposit is different, the temperature must be adjusted. Furthermore, even if the materials to be cut are different, more adjustments are required. In the present invention, data collection and experiments on various material properties are performed, and the present invention can be widely applied to many router materials and deposits.
[Brief description of the drawings]
FIG. 1 is a system diagram of a low-temperature PVD method according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a working principle according to an embodiment of the present invention.
(1) ARK power supply
(2) Bias power supply
(3) Trigistor
(4) Target
(5) Reaction gas
(6) Pump (diffusion pump and mechanical pump)
(7) Conical fitting
(8) Direction of rotation of the fixture
(9) Revolution direction of work frame
(10) Anode
(11) Metal ion
(12) Evaporated metal atom
(13) Filter
(14) Plasma Zone
(15) Ion source
(16) Micro droplet

Claims (3)

A step of placing a micro router on a fixture and performing cleaning and drying with an electron beam under normal conditions, a step of placing the fixture on which the micro router is placed in a vacuum furnace, making it in a vacuum state, and heating to 120 to 380 ° C. And washing the surface of the micro router with ions, coating the surface of the micro router with a low-temperature PVD method, and minimizing ions ejected from the Zr / Hf alloy target using an ion assist device and a filter, A Zr _x Hf _x C _x N _x composite thin film comprising a step of forming a thin film on a micro router , a step of passing a C ₂ H ₂ gas, and a step of cooling the micro router in a nitrogen atmosphere. Manufacturing method. The method of manufacturing a Zr x Hf _x C _x N _x composite thin film according to claim 1, wherein the material of the micro router is cermet and the target is a Zr / Hf alloy. The method for producing a Zr x Hf _x C _x N _x composite thin film according to claim 1, wherein the material of the micro router is a tungsten carbide alloy and the target is a Zr / Hf alloy.

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