KR20030073623A - Hybrid Method of AIP and Sputtering for Superhard coatings Ti-Si-N - Google Patents

Abstract

PURPOSE: A method for three-dimensionally depositing Ti-Si-N based rigid coating film on mold, high speed steel tool or hard metal tool through hybrid process of arc ion plating and sputtering is provided. CONSTITUTION: In a method for depositing a Ti-Si-N based rigid coating film on the surface of mold and tool through arc ion plating and sputtering, the method for depositing the Ti-Si-N based rigid coating film comprises first step (S12,S13) of evacuating a chamber in which the mold and tool are installed, and heating the chamber; second step (S14) of cleaning the mold and tool by flowing Ar gas into the chamber and impressing bias to the Ar gas; third step (S15) of blocking inflow of Ar gas into the chamber, applying vacuum into the chamber and heating the chamber again; fourth step (S16) of flowing Ar gas and N2 gas into the chamber and impressing bias to the Ar gas and N2 gas; and fifth step (S17) of depositing a Ti-Si-N based rigid coating film on the surface of the mold and tool by impressing power supply to Ti target using the arc ion plating and Si target using the sputtering respectively.

Description

Hybrid Method of AIP and Sputtering for Superhard coatings Ti-Si-N}

The present invention relates to a Ti-Si-N-based hard coating film deposition method, in particular, through a hybrid process of the arc ion plating (hereinafter referred to as 'AIP') method and the sputter method (sputter method) The present invention relates to a method of depositing a Ti-Si-N-based hard coating film in a three-dimensional three-dimensional high speed tool, a cemented carbide tool, or the like.

The Ti-Si-N-based hard coating film refers to a material in which Si is added to TiN within a range of 0 to 30 at%. The Ti-Si-N-based hard coating film surrounds TiN in a nano crystal structure by amorphous α-Si ₃ N ₄ . As a protective film material having an extremely high hardness, it is used in advanced industrial technology for coating tools and the like.

As the technology of modern industrial society is advanced and high precision, efforts are being made to increase productivity in various manufacturing and processing industries. As a result, it is inevitable to apply a protective hard coating film having excellent wear resistance, oxidation resistance, toughness, high temperature stability and durability through surface treatment to cutting tools such as high-speed tools or cemented carbide tools. That is, wear resistance is aimed at by forming hard films, such as TiN, TiCN, or TiAlN, on the surface of a product.

TiN coating film, which has been commercialized since the 1970s, has been limited in its application as it is easily oxidized in a high temperature oxidizing atmosphere despite its excellent mechanical properties. Therefore, in order to further improve the oxidation resistance and mechanical properties of TiN thin films, studies on composite component materials are being actively conducted. Also, a hard coating having excellent high temperature oxidation resistance in response to cutting of high hardness materials or high-speed cutting It is producing TiAlN thin film coated products through sputtering method and AIP method.

Further development of hard coatings is not only ternary composite materials such as TiAlN, but technology improvement through ternary composite materials has also been proposed. Among the ternary composite materials, the Ti-Si-N-based hard coating film has attracted attention because of its superior superhardness characteristics compared to TiN and TiAlN coating films and superior oxidation resistance at higher temperatures than TiN.

There are a number of methods for coating cutting tools, but these methods have different characteristics, so it is important to select the optimum thin film manufacturing method according to the characteristics and application of the thin film to be deposited.

Since the TiC coating was developed by the Chemical Vapor Deposition (CVD) method in the 1950s, the CVD method began to be widely used in the mid-1970s and is now widely used in multilayer coatings in early stage single layer coatings. In addition, PACVD (Plasma Assistance Chemical Vapor Deposition) using plasma has been developed and commercialized by supplementing the deposition process performed at a high temperature of 1000 ° C. or higher.

In addition, the CVD apparatus has advantages in that its structure is simple, can be easily applied to a large number of materials, and has a very high production yield compared to a PVD (Physical Vapor Deposition) apparatus. However, the CVD method is still difficult to apply to a low melting point substrate due to a relatively higher deposition temperature than other processes, and furthermore, there are problems such as atom diffusion into the substrate and thermal stress when cooled to room temperature. In addition, an increase in process temperature leads to a cost increase in actual industrial sites.

PVD is a technology that showed excellent performance by applying TiN single layer coating in 1980 and applied for the first time in interrupted cutting and sharp day. The representative method of PVD technique is sputter method, and the development of magnetron sputter method among sputter methods enables thin film at low temperature and high speed, and thus makes excellent thin film production.

In addition, the sputtering method can be manufactured while strictly controlling the composition and properties of the high melting point material or the active material, and has the advantage of less contamination by impurities compared to the CVD method. However, the sputtering method has a disadvantage in that the use efficiency of the magnetic material cannot be captured efficiently due to the deterioration of the leakage magnetic flux from the target surface and the target erosion is not uniform. In addition, the sputtering method is an improvement to solve the problems such as controlling the composition of the thin film, controlling the gas pressure, manufacturing the multilayer film, and improving the quality of the film while satisfying all existing requirements in the current situation where faster deposition speed and practical characteristics are required. This is necessary.

In addition, the CVD method and the PVD method are obstacles to practical use due to the low adhesion with the base material.

And, the ion plating method (ion plating) has been used as the main commercialization technology in the industry until recently, but the situation is being replaced by the emergence of a new ARC (Arc ion plating) method. The AIP method sufficiently compensates the disadvantages of the CVD, sputtering and ion plating methods mentioned above in the coating process, and can be applied to various base materials due to the high deposition rate at low temperature. In addition, the AIP method has excellent adhesion due to ions and particle bombardment. In addition, the AIP method is excellent in density due to high ionization rate and high kinetic energy of ions, and is well received in the coating industry because of its excellent surface coating property and uniformity even in a complicated base material. As such, the AIP method is difficult to apply to Si (ceramic) targets, although it has many advantages over other processes. Therefore, the Ti-Si-N type hard coat film cannot be deposited by AIP method.

B. Rother 《Surface and coating technology 142-144 (2001) 402-405》 developed a technique for depositing Ti-Si-N thin films by applying Ti and Si composite targets to the AIP method. However, this technique is a synthetic target applied to the AIP method, it is not possible to control the composition change during the deposition of the thin film, due to the difference in the ionization rate of Ti and Si during the process can be deposited a thin film of non-uniform composition. As a result, there is a great difficulty in mass production due to the decrease in reproducibility.

Korean Patent Registration No. 323991 (Invention name: thin film manufacturing method and manufacturing apparatus) uses a single equipment to manufacture various thin film manufacturing technologies such as vacuum deposition and sputtering, ion plating, ion implantation, UV coating, and plasma etching. Techniques have been disclosed for producing thin films simultaneously or in combination of these techniques.

Since the ion plating method used in Patent Registration No. 323991 generally uses a liquid evaporation source, evaporation always occurs up and down, thereby designing the equipment to be coated in only one direction in designing a complicated shape. The coating of the tool having the disadvantage is difficult to apply. In addition, the technology of the Patent No. 323991 has a disadvantage that all the gun (gun) is installed in the center and the specimen holder is made around the three-dimensional three-dimensional coating is difficult.

Accordingly, the present invention has been made to solve the problems of the prior art as described above, Ti-Si-N in three-dimensional three-dimensional mold, high-speed coating or cemented carbide tools through a hybrid process of the arc ion plating method and sputtering method It is an object of the present invention to provide a method of depositing a hard coating film.

1 is a block diagram of a deposition method of a Ti-Si-N-based hard coating film according to an embodiment of the present invention,

2a and 2b is a front view and a side view showing the components of the deposition apparatus of the Ti-Si-N-based hard coating film according to the present invention,

3 is a schematic diagram schematically showing a chamber of the deposition apparatus shown in FIG. 2A,

4A is a plan view schematically illustrating the structure of the planetary gear for rotating the support holder in the chamber shown in FIG. 3;

4B is a cross-sectional view of the planetary gear shown in FIG. 4A taken along line A-A.

5 is a graph showing the Si content in the Ti-Si-N-based hard coating film with respect to Si current in the present invention,

6 is a graph showing the results of X-ray diffraction analysis according to the amount of Si added in the Ti-Si-N-based hard coating film in the present invention,

Figure 7 is a graph showing the results of analyzing the bonding form of Si in the Ti-Si-N-based hard coating film in the present invention through XPS.

8 is a view showing a comparison of the microhardness of the conventional hard coating film and the Ti-Si-N-based hard coating film according to the present invention,

9 is a graph showing the change in the microhardness according to the content of Si in the Ti-Si-N-based hard coating film deposited by the present invention.

♠ Explanation of symbols on the main parts of the drawing ♠

21: chamber 22: drive motor

23: rotating shaft 24: rotary pump

25: roughing valve 26: gas inlet

27: Cliyo Pump 28: Main Valve

31: support holder 32: sputter gun

33: arc gun 40: planetary gear

The vapor deposition method of the present invention for achieving the above object, the first step of applying a vacuum in the chamber in which the mold, tool and the like is installed, cleaning the mold, tool and the like by introducing Ar gas into the chamber and applying a bias A second step of blocking the inflow of Ar gas into the chamber and applying a vacuum and heating the chamber again, and a fourth step of introducing Ar gas and N ₂ gas into the chamber and applying a bias to the chamber; And a fifth step of depositing a Ti-Si-N-based hard coating film on the surface of the mold and the tool by applying power to the Ti target using the AIP method and the Si target using the stuffer method, respectively. It is characterized by.

The present invention is to deposit a hard coating film of at least ternary (Ti-Si-N) or the like into a mold, a high-speed coating tool, or a cemented carbide tool through a hybrid process of the AIP method and the sputtering method. That is, in the present invention, the Ti-Si-N-based hard coating film is deposited on a mold, a high-speed coating tool, or a cemented carbide tool by using a conventional PACVD method, a sputtering method, or an AIP method using a Ti or Si composite target, respectively. Through a sputtering hybrid process, Ti-Si-N-based hard coating films are deposited on high-speed coatings or cemented carbide tools.

As described above, the present invention introduces the AIP method having a great advantage in the coating film deposition of the tool, and focuses on the difficulty in applying the Si target to the AIP method, and applies the Si target by the sputtering method. That is, in the present invention, the Ti-Si-N-based hard coating film is deposited on a mold, a high-speed coating tool, a cemented carbide tool, or the like by using the AIP method for the Ti target and the sputtering method for the Si target.

The AIP method applied to the present invention does not require a liquid evaporation source, and thus there is no reservoir for storing the evaporation source, so that the AIP gun and the sputter gun are mounted in the chamber, and the wall surface of the chamber is not restricted by the mounting position. The guns can be mounted in the desired position, top or bottom. Therefore, in coating a mold, a high speed tool, a cemented carbide tool, etc. using the AIP method, even if the shape has a complicated three-dimensional shape, uniform coating is possible.

In addition, in using the AIP method, the relative number of the AIP gun and the sputter gun can be adjusted as necessary, so that the content control of the deposition components (Ti and Si) can be more easily controlled when the thin film is deposited. . In addition, in using the AIP method, a support holder for supporting a high speed tool, a cemented carbide tool, or the like can be configured to rotate or rotate independently or simultaneously, and the rotational speed thereof can be adjusted to enable uniform three-dimensional coating.

Hereinafter, with reference to the accompanying drawings a preferred embodiment of the Ti-Si-N-based hard coating film deposition method according to the present invention will be described in detail.

The deposition method of the present invention is made through a deposition apparatus configured as shown in Figures 2a to 3 adapted to suitably apply the conventional deposition apparatus to the present invention.

1 is a block diagram of a deposition method of the Ti-Si-N-based hard coating film according to an embodiment of the present invention, Figures 2a and 2b is a configuration of the deposition apparatus of the Ti-Si-N-based hard coating film according to the present invention Front and side views showing the elements, FIG. 3 schematically showing a chamber of the deposition apparatus shown in FIG. 2A.

As shown in Figures 1 to 3, in the deposition method of the present invention, first, a mold, a high speed tool, a cemented carbide tool, or the like (hereinafter referred to as a specimen) is mounted on the support holder 31 shown in FIG. . Then, the support holder 31 on which the specimen is mounted is fixed to the substrate to allow both revolution and rotation. As a result, the specimen is capable of both rotating and rotating at the same time.

As described above, when the specimen is mounted to be capable of rotating and rotating, the chamber door is closed and the chamber 21 is sealed. Then, the idle and rotating switches of the control unit are turned on. Then, the substrate revolves and rotates through the rotating shaft 23 receiving the power of the driving motor 22 located outside the chamber 21. For this reason, the support holder 31 and the specimen also rotate and rotate (S11).

Then, the rotary pump switch of the control device is turned on to operate the rotary pump 24, and the roughing valve 25 is opened to wait until the vacuum in the chamber 21 becomes 10 ⁻² torr (S12). In this way, when the vacuum in the chamber 21 reaches 10 ^-2 Torr, the heater switch of the control device is turned on to activate the heat generating portion in the chamber 21. At this time, it sets by operating the temperature setting switch of a control apparatus so that the temperature in the chamber 21 may rise to 200 degreeC. When the temperature in the chamber 21 is 200 ° C. or more, the control device automatically cuts off the power applied to the heat generating unit, and supplies the power again at a temperature below that, so that the temperature in the chamber 21 is kept constant. It is configured to be maintained (S13).

With the temperature in the chamber 21 maintained at 200 ° C., the power of the control terminal of the control device is turned on, and the Ar flow rate control terminal is adjusted to set the amount of Ar gas to be injected. Then, when the gas injection valve switch of the control device is opened, Ar gas is injected into the chamber 21. That is, the amount of Ar gas discharged from the gas cylinder is adjusted through a flow meter and injected into the chamber 21 through the gas inlet 26.

Then turn on the bias power supply of the control device and then turn on the biasing switch on the control panel of the bias power supply. Then set the bias voltage adjusting switch to -600V. At this time, the voltage applied from the bias power supply device is applied to the specimen holder 31 and the specimen through the substrate to rotate and rotate. When Ar is injected and a bias is applied, plasma is formed on the specimen and the substrate, and pretreatment (cleaning) of the specimen by Ar ions is performed (S14).

After the pretreatment of the specimen by Ar ions, the bias power is first cut off and then Ar gas is blocked. At this time, the rotary pump 24 continues to operate so that the pressure in the chamber 21 is maintained at a vacuum of 10 ⁻² torr. In this state, the roughing valve 25 is closed and the rotary pump is switched off. Then, the main valve 28 connected to the cryo pump 27 is opened and the cryo pump 27 is operated until the interior of the chamber 21 is a vacuum of 10 ⁻⁶ torr. Then, the temperature setting switch of the control device is operated again to set the temperature set at 200 ° C to 300 ° C. Then, it waits until the temperature in the chamber 21 becomes 300 degreeC (S15).

Thus when the temperature in the chamber (21) 300 ℃, by the operation control device sets the flow rate of the Ar gas and N ₂ gas respectively. Then, operating the Ar gas and N ₂ gas inlet switch to open the valve to inject the Ar gas and N ₂ gas into the chamber (21). Then, the bias voltage control switch of the control device is operated to adjust the bias to -100V to apply a bias voltage to the specimen and the substrate (S16).

Then, turn on the power switch of the sputter power supply and the arc power supply of the control device, and adjust the control panel of the sputter power supply to apply proper power. Also, the control panel of the arc power supply device is adjusted to apply proper power. Then, a plasma is formed while power is applied to the sputter gun 32 and the arc gun 33, thereby depositing a Ti-Si-N-based (nano-TiN / α-Si ₃ N ₄ ) hard coating film on the specimen (S17). ).

The most important content of Ti and Si constituting the Ti-Si-N-based hard coating film deposited on the specimen is the number of constituting the sputter gun 32 and the arc gun 33 and the current strength applied to each target. Controlled by adjustment. Therefore, the Si content in the Ti-Si-N-based hard coat film can be controlled by fixing the Ti current applied through the arc gun 33 and adjusting the Si current applied through the sputter gun 32. And, when depositing a multi-element thin film through the present invention, by controlling the current of each target finely, it is possible to control the content of each component.

4A is a plan view schematically illustrating the structure of the planetary gear for rotating the support holder in the chamber illustrated in FIG. 3, and FIG. 4B is a cross-sectional view of the planetary gear illustrated in FIG. 4A taken along line A-A.

As shown in FIGS. 4A and 4B, the planetary gear 40 is located at the outermost side and has an internal gear 41 having a predetermined tooth and a rotation shaft 46 which receives power from a motor (not shown). Connected to the planet carrier 43 to simultaneously perform the function of the sun gear, and the planet carrier 43 and the interlocking with the internal gear 41 can be rotated along the surface of the planet carrier 43 and the It is composed of a plurality of planetary gears 42 to play a role.

And, between the planet gear 42 and the planet carrier 43 is a ceramic ball 44 which serves as a bearing so that the planet gear 42 can rotate along the surface of the planet carrier 43 while minimizing friction It is inserted. Therefore, the planet gear 42 revolves with the planet carrier 43 as the planet carrier 43 rotates, and engages with the internal gear 41 to rotate the planet carrier 43 through the ceramic ball 44. Rotate along the surface.

In addition, the substrate of the present invention is configured to allow both revolution and rotation at the same time through the structure of the planetary gear as described above, it may also be configured to enable each of the revolution or rotation through a conventional method. As a result, the specimen can be rotated and rotated at the same time, or can be rotated or rotated respectively.

5 is a graph showing the Si content in the Ti-Si-N-based hard coating film with respect to Si current in the present invention, Figure 6 is an X-ray according to the addition amount of Si in the Ti-Si-N-based hard coating film in the present invention It is a graph showing the diffraction analysis results. And, Figure 7 is a graph showing the results of analyzing the bonding form of Si in the Ti-Si-N-based hard coating film in the present invention by XPS (X-ray photoelectron spectroscopy).

As can be seen in Figures 5 to 7, the change in the content of Si according to the Si current of the deposited thin film is analyzed by EPMA (Electron Probe Microanalysis), the result of XRD (X-ray Diffractometer), Based on the results analyzed through XPS, it can be seen that an appropriate amount of Si (Si containing; 0-30 at% Si) is added to the TiN structure as amorphous α-Si ₃ N ₄ . That is, as shown in Figure 5, it can be seen that the Si content in the Ti-Si-N-based hard coating film also increases as the Si current increases. And, as shown in Figure 6, TiN deposited by the conventional AIP method has two diffraction peaks on the (111), (222) plane, but when adding Si through the method of the present invention The crystal growth behavior has a multi-orientation such as (111), (200), (220), (311), and (222) depending on the amount of the addition, and has the highest hardness value at that time. And, as shown in Figure 7, it can be seen that despite the increase in the amount of addition of Si is present in the amorphous α-Si ₃ N ₄ phase instead of pure Si in TiN. The presence of pure Si in the Ti-Si-N-based hard coat film causes a decrease in hardness.

8 is a view showing a comparison of the microhardness of the conventional hard coating film and the Ti-Si-N-based hard coating film according to the present invention. As shown in FIG. 8, the average microhardness of TiN deposited by conventional PACVD, sputtering, and AIP methods is 1500-2300 Kg / mm ² , and the microhardness of TiAlN is 3000 Kg / mm ^2, which is deposited by the present invention. It can be seen that the nano-TiN / α-Si ₃ N ₄ coating film has an ultra high hardness of 4500 Kg / mm ² or more.

9 is a graph showing the change in the microhardness according to the content of Si in the Ti-Si-N-based hard coating film deposited by the present invention. As shown in FIG. 9, the hardness of Si added to the Ti-Si-N-based hard coat film is increased up to 8at%, but when it is higher, the hardness may be decreased. Therefore, in depositing the Ti-Si-N-based hard coat film, it is possible to deposit the Ti-Si-N-based hard coat film having the most ideal hardness value by selecting the most suitable Si current strength.

As described in detail above, the deposition method of the present invention is an ultra-hard Ti-Si-N-based hard coating film having a uniform surface coating property such as a mold, a high speed tool, or a cemented carbide tool having a complex shape through the hybrid process of the AIP method and the sputter method. Can be deposited.

In addition, the vapor deposition method of the present invention is also possible to synthesize a multi-element and multilayer thin film by using a ceramic target, which is difficult to be applied to the AIP method, in the sputtering method and another target in the AIP method.

In addition, the deposition method of the present invention extends the life of the tool by depositing a very hard Ti-Si-N-based hard coating film on complex surfaces such as molds, high-speed cutting tools, bearings, bites, drills, and end mills. It can be applied to various high value-added technology industries.

The technical details of the Ti-Si-N-based hard coating film of the present invention have been described above with reference to the accompanying drawings. However, the exemplary embodiments of the present invention have been described by way of example and are not intended to limit the present invention.

In addition, it is obvious that any person skilled in the art can make various modifications and imitations within the scope of the appended claims without departing from the scope of the technical idea of the present invention.

Claims (4)

In the method of depositing the Ti-Si-N-based hard coating film on the surface of the mold, tool, etc. by the arc ion plating method and the sputter method, A first step of applying and heating a vacuum in a chamber in which the tool, equipment, etc. are installed; A second step of introducing Ar gas into the chamber and applying a bias to clean the mold, the tool, and the like; A third step of blocking Ar gas inflow into the chamber and vacuuming and heating the chamber again; A fourth step of introducing Ar gas and N ₂ gas into the chamber and applying a bias; A fifth step of depositing Ti-Si-N-based hard coating film on the surface of the mold and tool by applying power to the Ti target using the arc ion plating method and the Si target using the stuffer method, respectively Ti-Si-N-based hard coating film deposition method comprising a. The Ti-Si-N-based hard coating film according to claim 1, wherein the first to fifth steps are performed in a state in which the mold, the tool, and the like simultaneously perform revolution and rotation in the chamber. Way. The method of claim 1, wherein the first to fifth steps are performed in a state in which the mold, the tool, and the like revolve or rotate in the chamber. 2. The Ti-Si-A method according to claim 1, wherein in the fifth step, three-dimensional three-dimensional coating is performed by applying power to the Ti target and the Si target in multiple directions such as a mold and a tool installed in the chamber. Deposition method of N-based hard coating film.