KR20210144446A - Thin film depostion apparatus and DLC thin film coating methos using the appartus - Google Patents

Abstract

The present invention relates to a thin film deposition apparatus and a DLC thin film coating method using the same, and more particularly, to a thin film deposition apparatus and a DLC thin film coating method that can coat a DLC thin film having excellent surface roughness while maintaining physical property of low friction by combining a thin film coating process of an existing physical vapor deposition method (PVD) and an existing chemical vapor deposition method (CVD) to coat the DLC thin film. To this end, the thin film deposition apparatus of the present invention includes a reaction chamber, a gas supply unit, a power supply unit, and a vacuum generation unit, and physical and chemical vapor depositions can be simultaneously performed on a target material in the reaction chamber.

Description

Thin film deposition apparatus and DLC thin film coating method using the same

The present invention relates to a thin film deposition apparatus and a DLC thin film coating method using the same. It relates to a thin film deposition apparatus capable of coating a DLC thin film having very excellent surface roughness while maintaining low-friction physical properties by making it possible and a DLC thin film coating method using the same.

DLC is an abbreviation of Diamond Like Carbon, which means an amorphous carbon film mainly composed of carbon and hydrogen.

DLC thin film is a surface deposition technology that has not only high hardness but also low friction properties on the surface. It has a great effect on the surface modification of various materials. is used, and various surface treatment techniques and deposition methods are being developed accordingly.

Existing surface treatment methods are largely chemical vapor deposition (CVD; Chemical Vapor Deposition, hereinafter referred to as 'CVD') and physical vapor deposition (PVD; Physical Vapor Deposition, hereinafter referred to as 'PVD') such as thin film coating and carburization. , and surface modification such as nitriding.

In this conventional surface treatment method, the process is performed at a high temperature of about 400 ~ 1,000℃ for the purpose of improving mechanical properties such as bonding strength and hardness. It has limitations in applying coatings to hot molds and ultra-precision molds used for shape processing of glass, metal and plastic products, and there are significant difficulties in terms of productivity and product quality improvement due to damage caused by thermal oxidation and abrasion.

On the other hand, as a coating method for forming the DLC thin film, a CVD method and a PVD method are mainly used, and the CVD method supplies a gas to a chamber and applies heat, plasma, and beam energy to energy. In this method of coating by decomposing the gas, the surface roughness is excellent and uniform coating is possible even on complex shapes, but it is difficult to control the coating speed and the thickness of the thin film, and the thin film may be deformed due to the difference in the coefficient of thermal expansion. There are disadvantages such as

In addition, the PVD method is a method of coating by evaporation and sputtering by creating a beam and a flow of gas to deposit a thin film on the substrate, so that low-temperature coating is possible, the process is simple, and the thermal, Although there is an advantage of less chemical modification, the adhesive strength is somewhat lowered, and if the process time is long, the surface roughness of the product due to macro particles may decrease, and thus the management of the system is difficult.

As such, since the CVD method and the PVD method have opposite advantages and disadvantages, the development of a new type of thin film deposition apparatus and DLC thin film coating method that can utilize both the advantages of the CVD method and the PVD method is difficult. It is urgently required.

1. Republic of Korea Patent Publication No. 10-0960852 (published on Jun. 07, 2010)

The present invention has been devised to solve the problems of the prior art as described above, and an object of the present invention is to coat a DLC thin film by combining a thin film coating process of a physical vapor deposition method (PVD) and a chemical vapor deposition method (CVD) together. An object of the present invention is to provide a thin film deposition apparatus capable of coating a DLC thin film having very excellent surface roughness while maintaining low friction physical properties and a DLC thin film coating method using the same.

The present invention for achieving the above object,

A thin film deposition apparatus comprising: a fixing jig for installing a target object, an ion beam source and a sputtering target; a reaction chamber having a plurality of reaction gas inlets and reaction gas outlets; A gas supply unit for supplying a reaction gas to the inside, a power supply unit for supplying power to the reaction chamber, and a vacuum generator connected to the reaction gas outlet to create a vacuum inside the reaction chamber, the reaction It is characterized in that it is configured to simultaneously perform physical vapor deposition and chemical vapor deposition on an object inside the chamber.

At this time, the gas supply unit includes a first gas supply unit for supplying Ar gas to the inside of the reaction chamber, _{a second gas supply unit for supplying C 2} H ₂ gas to the inside of the reaction chamber, and N ₂ gas to the inside of the reaction chamber. It characterized in that it is configured to include a third gas supply unit and a fourth gas supply unit for supplying external air to the inside of the reaction chamber.

In addition, the power supply unit comprises a first power supply for supplying power to the inside of the reaction chamber, a second power supply for supplying power to the ion beam source, and a third power supply for supplying power to the sputtering target. characterized in that

In addition, the vacuum generating unit includes a low vacuum pump for reducing the atmospheric pressure inside the reaction chamber to atmospheric pressure, a high vacuum pump connected between the low vacuum pump and the reaction gas outlet, and installed between the low vacuum pump and the high vacuum pump. It is characterized in that it is configured to include a vacuum control unit for controlling the driving of each pump by measuring the degree of vacuum in the auxiliary pump and the reaction chamber.

On the other hand, the DLC thin film coating method according to the present invention,

It relates to a method for coating a DLC thin film on the surface of a target object using a thin film deposition apparatus, and a pretreatment step of removing the oxide film on the surface of the object installed in a reaction chamber to modify the surface, and chemical vapor deposition on the surface of the pretreated object It is characterized in that it comprises a buffer layer forming step of forming a buffer layer, and a DLC thin film coating step of forming a DLC thin film coating on the buffer layer by simultaneously performing physical vapor deposition and chemical vapor deposition.

At this time, in the pretreatment step, Ar gas is supplied to the ion beam source using the gas supply unit, and power is supplied to the ion beam source through the power supply unit to modify the surface of the object fixedly installed in the fixing jig by the ions emitted from the ion beam source. characterized in that

In addition, the buffer layer forming step is characterized in that it comprises a first buffer layer forming step of forming a Cr layer on the surface of the modified object, and a second buffer layer forming step of forming a CrN layer on the Cr layer. .

According to the present invention, by simultaneously applying the PVD method and the CVD method to coat the DLC thin film, the disadvantages of each method can be minimized and only the advantages can be utilized, so that the physical properties of low friction are maintained and the surface roughness is very excellent. It has an excellent effect of coating the DLC thin film.

1 is a view conceptually showing a thin film deposition apparatus according to the present invention.
Figure 2 is a view showing a planar shape of the chamber of the present invention shown in Figure 1;
3 is a cross-sectional view showing a hierarchical configuration including a DLC thin film formed by the DLC thin film coating method according to the present invention.
Figure 4 is a flow chart sequentially showing the DLC thin film coating method according to the present invention.

Hereinafter, preferred embodiments of the thin film deposition apparatus and the DLC thin film coating method using the same according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a view conceptually showing a thin film deposition apparatus according to the present invention, FIG. 2 is a view showing a planar shape of a chamber of the present invention shown in FIG. 1, and FIG. 3 is a view showing a DLC thin film coating method according to the present invention. It is a cross-sectional view showing a hierarchical configuration including a DLC thin film, and FIG. 4 is a flowchart sequentially showing a DLC thin film coating method according to the present invention.

The present invention provides a DLC thin film with excellent surface roughness while maintaining low friction physical properties by combining the physical vapor deposition method (PVD) thin film coating process and chemical vapor deposition method (CVD) to coat the DLC thin film. It relates to a thin film deposition apparatus 100 for coating and a DLC thin film coating method using the same. First, the thin film deposition apparatus 100 according to the present invention is largely a reaction chamber 110, a gas supply unit, as shown in FIG. 1 . 120 , a power supply unit 130 , and a vacuum generator 140 .

More specifically, the reaction chamber 110 is to allow the DLC thin film to be deposited on the object 10 accommodated therein, and a fixing jig 112 for fixing the object 10 therein, and PVD An ion-beam source 114 and a sputtering target 116 for performing the method are installed.

At this time, the ion beam source 114 forms a closed drift loop using a cathode and an anode, and has a structure in which electrons are moved at high speed along this circulation space, and the surface of the object 10 is modified. or thin film deposition.

That is, it is configured such that an ion generating gas, that is, an ionizing gas such as Ar gas (argon gas), is continuously supplied from the outside of the reaction chamber 110 in the closed space in which the electrons move, and the ion beam source is generated by the supplied gas. (114) Plasma is generated inside, and it is configured to eject ions by diffusion due to the pressure difference between the inside and the outside. The straightness of the ion beam is good.

More specifically, in the ion beam source 114, ions ionized by a high voltage and magnetic field of an anode in an ionization region are extracted from a plasma formed by a magnetic field with enhanced internal magnetic force, and the ionized material Accordingly, a high voltage of 1,000 to 3,000 V is applied to the anode by the power supply 130 to be described later, so that the ion particles accelerated by the high voltage collide with the target 10 at high speed to modify or coat the surface. it is configured to

Next, the sputtering target 116 is similarly used in the PVD method, and a graphite target or the like may be used.

That is, when a strong voltage is applied into the reaction chamber 110 by a voltage supply unit to be described later in a state in which Ar gas is introduced into the reaction chamber 110 in a vacuum state, accelerated free electrons collide with the Ar gas to generate plasma, At this time, the ionized Ar+ collides with the sputtering target 116 to which a negative (-) voltage is applied by the voltage supply unit, and serves to allow the protruding deposition materials to be deposited on the target object 10 .

At this time, since the ion beam source 114 and the sputtering target 116 are also used in a thin film deposition apparatus for performing the conventional PVD method, a more detailed description thereof will be omitted.

In addition, as shown in FIG. 2 , a plurality of reaction gas inlets 113 and one reaction gas outlet 115 are formed in the reaction chamber 110 , and the reaction gas inlet 113 has a gas supply unit to be described later. 120 is connected and configured to supply reaction gases to be used in the PVD process and the CVD process in the reaction chamber 110 into the reaction chamber 110 .

In addition, the reaction gas outlet 115 serves to discharge the reaction gases injected into the reaction chamber 110 , and a vacuum generator 140 to be described later is connected to the reaction gas outlet 115 to be installed in the reaction chamber. It is configured to maintain the inside of the 110 in a vacuum state.

On the other hand, a feedthrough (not shown) for supplying external power to the inside of the reaction chamber 110 and components for maintaining the inside of the reaction chamber 110 in a vacuum state may be additionally installed. .

Next, the gas supply unit 120 serves to supply reaction gases to be used in the PVD process and the CVD process into the reaction chamber 110, and a plurality of reaction gas inlets formed in the reaction chamber 110 ( 113) is connected and installed.

In more detail, the gas supply unit 120 includes first to fourth gas supply units 122, 124, 126, and 128. First, the first gas supply unit 122 is introduced into the reaction chamber 110 by Ar (argon). It serves to supply the gas, and Ar gas is a DLC thin film coating method by surface modification and PVD method of the target object 10 in the pretreatment step (S10) and the DLC thin film coating step (S30) of the DLC thin film coating method to be described later. is used for

Next, the second gas supply unit 124 is C ₂ H ₂ (acetylene) into the inside of the reaction chamber 110 . It serves to supply the gas, and C ₂ H ₂ gas is used for coating the DLC thin film by the CVD method in the DLC thin film coating step (S30) of the DLC thin film coating method to be described later.

In this case, as the gas supplied from the second gas supply unit 124 to the inside of the reaction chamber 110 , other methane gas streams may be used instead of the _{C 2} H _{2 gas.}

Next, the third gas supply unit 126 is N ₂ (nitrogen) into the inside of the reaction chamber 110 . It serves to supply a gas, and the N ₂ gas is used in a second buffer layer forming step ( S24 ), which will be described later.

At this time, the first to third gas supply units 122 , 124 , and 126 include a storage tank (not shown) for storing the gas to be supplied into the reaction chamber 110 , and the reaction gas inlet 113 of the storage tank and the reaction chamber 110 . ) and a pump (not shown) for generating a flow of reaction gas and a pipe connected between them, and a valve 121 and a flow controller (MFC; Mass Flow Controller) 125 are installed in each pipe. to control whether or not gas is supplied to the reaction chamber 110 through the control of the valve 121, and to control the flow rate of the gas supplied to the reaction chamber 110 by the control of the flow controller 125 has been

In addition, the fourth gas supply unit 128 serves to supply external air to the inside of the reaction chamber 110 , and in a vacuum state for the installation and separation of products before and after all processes, that is, the target object 10 . It is an air supply device to adjust to atmospheric pressure.

Next, the power supply unit 130 is connected to the reaction chamber 110 and serves to supply power to be used in the CVD method and the PVD method for DLC thin film coating, and the first to third power supply devices 132, 134, 136. is made including

First, the first power supply device 132 supplies power to the inside of the reaction chamber 110 , and the power supplied to the inside of the reaction chamber 110 through a feed-through provided in the reaction chamber 110 is By forming the plasma, it serves to form a thin film on the target object 10 by the CVD method.

Next, the second power supply device 134 supplies power to the ion beam source 114 provided in the reaction chamber 110 . As described above, the power supplied to the ion beam source 114 is the ion beam source. It serves to allow the release of ions from (114).

In addition, the third power supply device 136 supplies power to the sputtering target 116 provided in the reaction chamber 110, and may generate plasma by applying a cathode to the sputtering target 116 to form an electric field. plays a role in making

In this case, although not shown, the power supply unit 130 may further include a control unit for controlling the size of the power supplied from the first to third power supply units 132 , 134 , and 136 to be varied.

Next, the vacuum generator 140 is connected to the reaction gas outlet 115 of the reaction chamber 110 so that the reaction gases inside the reaction chamber 110 can be discharged to the outside and at the same time the reaction chamber 110 It serves to maintain the inside in a vacuum state, and includes a low vacuum pump 142 , a high vacuum pump 144 , an auxiliary pump 146 , and a vacuum control unit 148 .

More specifically, the low vacuum pump 142 serves to reduce the atmospheric pressure inside the reaction chamber 110 to atmospheric pressure, and the high vacuum pump 144 reduces the atmospheric pressure inside the reaction chamber 110 to a vacuum state. The auxiliary pump 146 serves to maintain the back pressure of the high vacuum pump 144 below a threshold value, and to make the inside of the reaction chamber 110 in a vacuum state. To do this, first, the atmospheric pressure inside the reaction chamber 110 is lowered to some extent by using the low vacuum pump 142 , and then the high vacuum pump 144 is driven so that the inside of the reaction chamber 110 is in a vacuum state.

At this time, as shown in FIG. 1 , the high vacuum pump 144 is installed between the low vacuum pump 142 and the reaction gas outlet 115 , and the auxiliary pump 146 is the low vacuum pump 142 and the high vacuum pump. It is installed between the 144, each pump is connected to each other by a pipe, a branch pipe is formed between the auxiliary pump 146 and the high vacuum pump 144, and the branch pipe has a relief valve (relief valve) ) 145 is installed to adjust the gas pressure in the pipe.

Next, the vacuum control unit 148 serves to control the operation of the vacuum generator 140 , and is installed around the reaction gas outlet 115 of the reaction chamber 110 to control the degree of vacuum inside the reaction chamber 110 . It is measured and serves to control the driving of each pump (142, 144, 146) according to the measurement result.

On the other hand, the DLC thin film coating method according to the present invention relates to a method for coating a DLC thin film on the surface of the target object 10 using the above-described thin film deposition apparatus 100. Hereinafter, the target object having hard chrome plating on the surface A DLC thin film coating method according to the present invention will be described with reference to (10).

As shown in FIG. 4 , the DLC thin film coating method according to the present invention includes a pretreatment step (S10), a buffer layer forming step (S20) and a DLC thin film coating step (S30).

First, the pretreatment step (S10) is a step of modifying the surface of the target object 10, such as removing an oxide film on the surface of the target object 10 using the thin film deposition apparatus 100, and is emitted from the ion beam source 114. The surface of the target object 10 is modified using ions.

More specifically, in the pre-processing step (S10), the vacuum generator 140 is driven while the object 10 for forming the DLC thin film is mounted in the fixing jig 112 of the reaction chamber 110 to drive the reaction chamber ( After the interior of 110 is in a vacuum state, the first gas supply unit 122 is driven to supply Ar gas to the inside of the reaction chamber 110 and to the ion beam source 114 through the second power supply unit 134 . supply power.

The Ar gas supplied into the reaction chamber 110 is introduced into the ion beam source 114 to be ionized and released, and the surface of the target object 10 is modified by the Ar ions emitted from the ion beam source 114 .

Next, the buffer layer forming step (S20) relates to the step of forming a buffer layer on the surface of the target object 10 whose surface is modified by the CVD method, the first buffer layer forming step (S22) and the second buffer layer It consists of a forming step (S24).

First, the first buffer layer forming step (S22) is a step of forming the first buffer layer 20 on the surface of the target object 10, and the first buffer layer 20 is about 0.2 to 1 μm thick Cr (chromium). ) layer is formed.

That is, the reaction chamber 110 through the first power supply device 132 while injecting a high-purity inert gas, that is, Ar gas, into the reaction chamber 110 in a vacuum state where the target object 10 is mounted on the fixing jig 112 . When a high voltage (bias power) is supplied to the inside, plasma is formed, and as Ar gas is decomposed by the plasma, it is deposited on the surface of the object 10 to form a Cr layer.

Next, the second buffer layer forming step (S24) relates to the step of forming the second buffer layer 30 on the first buffer layer 20 formed in the first buffer layer forming step (S22), that is, the Cr layer. A CrN (chromium nitride) layer with a thickness of about 1 to 5 μm is formed on top of the Cr layer by using a CVD method.

That is, a high-purity reactive gas, that is, N ₂ gas is supplied into the reaction chamber 110 using the third gas supply unit 126 to form a CrN layer on the Cr layer of the target object 10 by the CVD method.

In this case, the N ₂ there the gas can be supplied through a plurality of gas injection hole 117 is radially formed on an upper portion of the reaction chamber 110, as shown in Figure 2, which is N ₂ gas of high purity is the reaction chamber This is to allow the plasma to be formed by the power supplied to the reaction chamber 110 by the first power supply device 132 so as to be more evenly supplied in the 110 .

The buffer layer thus formed serves to improve the affinity between the target object 10 and the DLC thin film, and since it is a conventionally used configuration, a more detailed description thereof will be omitted.

Next, the DLC thin film coating step (S30) relates to the step of forming the DLC thin film coating layer 40 with a thickness of about 0.5 to 1.5 μm on the buffer layer, that is, the CrN layer, and in the present invention, the reaction chamber 110 inside the The DLC thin film coating layer 40 is formed on the CrN layer of the target object 10 so that the plasma by the PVD method and the plasma by the CVD method are simultaneously formed.

In more detail, while maintaining a vacuum state inside the reaction chamber 110 using the vacuum generator 140 , the second gas supply unit 124 is used to move the C ₂ H _{2 into the reaction chamber 110 .} When the gas is supplied and power is supplied to the inside of the reaction chamber 110, the ion beam source 114, and the sputtering target 116 using the first to third power supply devices 132, 134, and 136 of the power supply unit 130, respectively. , it is possible to form the DLC thin film coating layer 40 on the CrN layer of the target object 10 while plasma by PVD and plasma by CVD are simultaneously generated inside the reaction chamber 110 .

Therefore, according to the thin film deposition apparatus 100 and the DLC thin film coating method using the same according to the present invention as described above, the PVD method and the CVD method are simultaneously applied inside the reaction chamber 110 constituting the thin film deposition apparatus 100 By making it possible to coat the DLC thin film, the disadvantages of each method can be minimized and only the advantages can be utilized, which has various advantages such as being able to coat the DLC thin film with excellent surface roughness while maintaining the physical properties of low friction. will be.

Although the above-described embodiments have been described with respect to the most preferred examples of the present invention, it is not limited to the above-described embodiments, and it is apparent to those skilled in the art that various modifications are possible without departing from the technical spirit of the present invention.

The present invention relates to a thin film deposition apparatus and a DLC thin film coating method using the same. It relates to a thin film deposition apparatus capable of coating a DLC thin film having very excellent surface roughness while maintaining low-friction physical properties by making it possible and a DLC thin film coating method using the same.

10: object 20: first buffer layer
30: second buffer layer 40: DLC thin film coating layer
100: thin film deposition device 110: reaction chamber
112: fixing jig 113: reaction gas inlet
114: ion beam source 115: reaction gas outlet
116: sputtering target 117: gas injection hole
120: gas supply 121: valve
122: first gas supply unit 124: second gas supply unit
125: flow controller 126: third gas supply unit
130: power supply 132: first power supply device
134: second power supply device 136: third power supply device
140: vacuum generator 142: low vacuum pump
144: high vacuum pump 145: relief valve
146: auxiliary pump 148: vacuum control unit
S10: pretreatment step S20: buffer layer forming step
S22: first buffer layer forming step S24: second buffer layer forming step
S30: DLC thin film coating step

Claims (7)

In the thin film deposition apparatus,
A fixing jig for installing a target object, an ion beam source and a sputtering target, and a reaction chamber having a plurality of reaction gas inlets and reactive gas outlets formed therein;
a gas supply unit connected to the reaction gas inlet to supply the reaction gas to the inside of the reaction chamber;
a power supply for supplying power to the reaction chamber; and
and a vacuum generator connected to the reaction gas outlet to make the inside of the reaction chamber in a vacuum state,
A thin film deposition apparatus, characterized in that it is configured to simultaneously perform physical vapor deposition and chemical vapor deposition on a target object in the reaction chamber.
The method of claim 1,
The gas supply unit includes a first gas supply unit supplying Ar gas into the reaction chamber, _{a second gas supply unit supplying C 2} H ₂ gas into the reaction chamber, and a second gas supply unit supplying N ₂ gas into the reaction chamber. A thin film deposition apparatus comprising a third gas supply unit and a fourth gas supply unit for supplying external air to the inside of the reaction chamber.
The method of claim 1,
The power supply unit comprises a first power supply for supplying power to the inside of the reaction chamber, a second power supply for supplying power to the ion beam source, and a third power supply for supplying power to the sputtering target. A thin film deposition apparatus with
The method of claim 1,
The vacuum generating unit includes a low vacuum pump for reducing the atmospheric pressure inside the reaction chamber to atmospheric pressure, a high vacuum pump connected between the low vacuum pump and the reaction gas outlet, and an auxiliary pump installed between the low vacuum pump and the high vacuum pump and a vacuum control unit controlling the driving of each pump by measuring the degree of vacuum in the reaction chamber.
It relates to a method of coating a DLC thin film on the surface of a target object using the thin film deposition apparatus according to any one of claims 1 to 4,
A pretreatment step of modifying the surface by removing the oxide film on the surface of the object installed in the reaction chamber;
A buffer layer forming step of forming a buffer layer using a chemical vapor deposition method on the surface of the pretreated object;
A DLC thin film coating method comprising a DLC thin film coating step of simultaneously performing physical vapor deposition and chemical vapor deposition to form a DLC thin film coating on the buffer layer.
6. The method of claim 5,
In the pretreatment step,
A DLC thin film characterized in that Ar gas is supplied to the ion beam source using a gas supply unit, and power is supplied to the ion beam source through the power supply unit to modify the surface of an object fixedly installed in a fixing jig by ions emitted from the ion beam source. coating method.
6. The method of claim 5,
The buffer layer forming step is,
A first buffer layer forming step of forming a Cr layer on the surface of the modified object;
DLC thin film coating method comprising a second buffer layer forming step of forming a CrN layer on the Cr layer.

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