KR20020037130A - Equipment of depositing silicide layer and method of preventing particle formation - Google Patents

Abstract

PURPOSE: An apparatus for depositing a silicide layer and a method for preventing generation of particles are provided to prevent the generation of particles by connecting a silane gas supply tube to a process chamber. CONSTITUTION: A process chamber(210) is used for depositing a tungsten silicide layer on a wafer by reacting supplied reaction gases. A gas supply system(220) is connected with the process chamber(210). The gas supply system(220) is used for supplying a reaction gas and an inert gas into an inside of the process chamber(210). A pump(290) is connected with the process chamber(210) by a vacuum tube(295). The pump(290) is used for controlling an internal pressure of the process chamber(210) in order to optimize an internal state of the process chamber(210). The gas supply system(220) is formed with three inert gas supply tubes(230,234,238), a silane gas supply tube(240), a DCS gas supply tube(250), a WF6 gas supply tube(255), and an NF3 gas supply tube(260). A multitude of opening/shutting valve(232,236,239,242,252,256,262), a filter(222), a gas flow controller(224) are installed at each gas supply tube(230,234,238,240,250,255,260).

Description

Equipment of depositing silicide layer and method of preventing particle formation}

The present invention relates to a silicide film deposition apparatus, and more particularly, by connecting a silane gas supply pipe alone to a process chamber, a silicide film for preventing generation of particles by mixing silane gas and tungsten gas in a gas supply line. A deposition facility.

In addition, the present invention relates to a method for preventing particle formation, and more particularly, after supplying silane gas to the process chamber to form a buffer layer on the wafer, the silane gas remaining between the silane gas supply pipe and the chamber is completely converted into an inert gas. The present invention relates to a method for preventing particle formation to prevent particles from being formed due to a reaction between the tungsten gas and the silane gas supplied after the silane gas supply by purging.

As the wiring resistance is increased due to the high integration of semiconductor devices, wiring with low specific resistance is required, which leads to a polyside structure wiring using a tungsten silicide (WSi _X ) film.

The tungsten silicide film is reacted with WF ₆ gas and silane gas (SiH ₄ ) by chemical vapor deposition (hereinafter referred to as CVD) to deposit on a polysilicon coated wafer.

The tungsten silicide film thus formed has a bad step coverage of 25% or less in a contact having a high aspect ratio, and the chlorine (Cl) content is increased in the film due to reaction by-products. When the content of chlorine in the tungsten silicide film is high, chlorine contained in the polysilicon film formed under the tungsten silicide film is converted into a tungsten silicide film, so that the thickness of the tungsten silicide film is thick and the thickness of the polysilicon film is thin, resulting in voids.

To solve these problems, before forming the tungsten silicide film, a buffer layer is formed on the polysilicon film using silane gas, and a tungsten silicide film is formed on the buffer layer. Here, the buffer layer formed on the polysilicon film prevents the polysilicon film from thinning due to chlorine.

Recently, a tungsten silicide film is formed on a buffer layer using a dichlorosilane (SiH ₂ Cl ₂ ; Dichloro silane, DCS) gas, which is less reactive than a silane gas, as a reducing agent for WF ₆ . As described above, when the tungsten silicide film is formed using the DCS gas, the content of chlorine is reduced by about two to three times as compared with when the tungsten silicide film is formed using the silane gas.

The process of forming the tungsten silicide film using the chemical vapor deposition method is as follows.

After the wafer on which the polysilicon film is formed is introduced into the process chamber, a plurality of valves installed in the silane gas supply pipe are opened in the gas supply system for supplying reaction gas and predetermined gases to the process chamber to supply silane gas to the process chamber. A buffer layer is formed over the silicon film.

Then, after closing all the valves of the silane gas supply pipe, the valves installed in the DCS gas supply pipe and the WF ₆ gas supply pipe are opened to supply the DCS gas and the WF6 gas to the process chamber. Here, the DCS gas and the WF ₆ gas are mixed in the gas supply line near the process chamber and then supplied to the process chamber to form a tungsten silicide film on the buffer layer.

Here, the silane gas supply pipe, the DCS gas supply pipe, and the WF ₆ gas supply pipe are connected to one pipe near the process chamber.

Therefore, after supplying the silane gas into the process chamber to form a buffer layer on the wafer, the WF ₆ gas remains between the silane gas supply pipe and the process chamber in the process of supplying the WF ₆ gas and the DCS gas into the process chamber. Reacting with the silane gas in the vicinity of the process chamber, cucumber-shaped particles having a length of 5 to 7 µm and a diameter of 1.5 µm are formed.

Cucumber particles thus formed are deposited together when the tungsten silicide film is deposited on the wafer to reduce the reliability of the semiconductor device.

Accordingly, an object of the present invention is to prevent silane gas and WF ₆ gas from being mixed in the gas supply line near the process chamber to prevent particles from forming during the deposition process of the tungsten silicide film.

Other objects of the present invention will become more apparent from the following detailed description and the accompanying drawings.

1 is a conceptual diagram schematically showing the structure of a CVD apparatus according to a first embodiment of the present invention.

2 is a flowchart showing a tungsten silicide film deposition process of the first embodiment.

Figure 3 is a process progress table showing a more detailed breakdown of the tungsten silicide film deposition process according to the first embodiment.

4 is a conceptual diagram schematically showing the structure of a CVD apparatus according to a second embodiment of the present invention;

5 is a conceptual view schematically showing the interior of a process chamber according to a second embodiment of the present invention.

6 is a flowchart illustrating a tungsten silicide film deposition process according to a second embodiment of the present invention.

7 is a conceptual diagram schematically showing the structure of a CVD apparatus according to a third embodiment of the present invention.

In order to achieve the above object, the present invention provides a silane gas supply pipe to the inside of the process chamber after supplying the silane gas into the process chamber in the CVD facility connected to the WF ₆ gas supply pipe by the connection pipe. After completely purging the silane gas, DCS gas and WF ₆ gas are supplied.

In addition, the present invention prevents the silane gas and the WF ₆ gas from being mixed by connecting the silane gas alone with the process chamber without connecting the silane gas with another gas supply pipe.

Hereinafter, a structure of a CVD facility and a method for preventing particles from being formed in a tungsten silicide film deposition process will be described with reference to FIGS. 1 to 5.

First, the structure of the CVD apparatus according to the first embodiment will be described with reference to FIG. 1.

<First Embodiment>

As shown in FIG. 1, the CVD apparatus 1 has a process chamber 10 in which a process of depositing a tungsten silicide film on a wafer by reacting largely supplied reaction gases and a process chamber in communication with the process chamber 10 are performed. The process chamber 20 is connected to the process chamber 20 through a gas supply system 20 and a vacuum tube 95 for supplying a reaction gas, an inert gas, or the like into the interior of the process unit 10, so as to maintain an optimal state for the process. It consists of a pump 90 to adjust the pressure inside.

Here, the gas supply system 20 includes three inert gas supply pipes 30, 34 and 38, a silane gas supply pipe 40 for supplying silane gas to form a buffer layer for protecting the polysilicon film formed on the wafer, A DCS gas supply pipe 50 and a WF ₆ gas supply pipe 55 for supplying DCS gas to form a tungsten silicide film on the upper surface of the buffer layer, and an NF ₃ gas supply pipe 60 for supplying NF ₃ gas, which is a cleaning gas, are included. do.

Each of the gas supply pipes 30, 34, 36, 40, 50, 55, and 60 has a plurality of on / off valves for opening and closing each gas supply pipe and a filter 22 for filtering impurities contained in the gas. And a gas flow rate control device 24 that controls the flow rate of the gas required for each step. In FIG. 1, only one open / close valve 32, 36, 39, 42, 52, 56, or 62 directly related to the present invention is shown among the plurality of open / close valves installed in each gas supply pipe. 1, the filter 22, the gas flow control device 24, the opening-closing valves 32, 36, 39, 42, 52, 56, 62, etc. are installed in each gas supply pipe in order.

Preferably, argon gas is introduced into the inert gas supply pipes (30, 34, 38). Among the three inert gas supply pipes (hereinafter referred to as "argon gas supply pipes"), the first argon gas supply pipe 30 is provided on the left side of the silane gas supply pipe 40 as shown in FIG. 1, and the second argon gas The supply pipe 36 is installed on the right side of the DCS gas supply pipe 50, and the third argon gas supply pipe 38 is installed between the second argon gas supply pipe 36 and the WF ₆ gas supply pipe 55.

On the other hand, the end portion of the first argon gas supply pipe 30 communicates independently with the side surface of the process chamber 10, and the silane gas supply pipe 40, the DCS gas supply pipe 50, and the second argon gas supply pipe 36 The ends are connected to each other by a first connecting tube 70. In addition, ends of the third argon gas supply pipe 38, the WF ₆ gas supply pipe 55, and the NF ₃ gas supply pipe 60 are connected to each other by the second connection pipe 80, and The first connecting pipe 70 communicates with the predetermined portion. An end of the second connecting pipe 80 is branched into two branch pipes 82 and 84 so as to communicate with the process chamber 10, respectively. A needle valve 86 is installed to adjust the amount of gas introduced into the inside.

Although not shown, each gas supply pipe is connected to the vent line, and a valve for venting is installed at a connection pipe connecting each gas supply pipe and the vent line.

A process of forming a tungsten silicide layer so that particles are not generated using the CVD facility configured as described above will be described with reference to FIGS. 2 and 3.

The process chamber 10 is made in an atmosphere suitable for forming a buffer layer on the wafer to prevent the thickness of the polysilicon film formed on the wafer from being thinned by the chlorine (Cl) group (S100).

That is, as shown in FIG. 3, the pump is driven to make the process chamber vacuum, and the internal temperature of the process chamber is gradually raised two times to create an atmosphere of the process chamber 10 suitable for forming the buffer layer.

As such, when the atmosphere of the process chamber 10 is established, the silane gas necessary for opening the open / close valves 42 installed in the silane gas supply pipe 40 in the gas supply system 20 to form a buffer layer is formed in the process chamber ( 10). Then, the silane gas is reacted in the process chamber 10 to deposit a predetermined thickness on the upper surface of the polysilicon film to form a buffer layer to protect the polysilicon film from the chlorine group (S110).

Here, the supply of the silane gas exhausts the silane gas through the vent line until the flow rate as needed to open the vent valve and deposit the buffer layer as shown in step No. S110 of FIG. 3 flows through the silane gas supply pipe 40. Let's do it. When the silane gas having the flow rate required to form the buffer layer flows through the silane gas supply pipe 40, the vent valve is closed and the open / close valve 42 is opened to supply the silane gas into the process chamber 10.

When the buffer layer is formed on the wafer by the reaction of the silane gas, the WF ₆ gas and the first and second connection pipes 70 and 80 and the process chamber 10 which are injected in a subsequent process after closing the on / off valve 42 are closed. In order to prevent the remaining silane gas from reacting to generate cucumber-shaped particles, the first and second connection pipes 70 may be formed using argon gas flowing through the first to third argon gas supply pipes 30, 36, and 38. 80 and purge the silane gas remaining in the process chamber 10 (S120).

That is, as shown in step S120 of FIG. 3, the first, second, and third argon gas supply pipes 30, 36, and 38 are open to all the opening and closing valves 32, 36, and 39. And supplying argon gas to the second connecting pipes 70 and 80 and the process chamber 10 to purge the remaining silane gas. Thereafter, the argon gas and the silane gas are completely removed by driving the pump 90 to pump the argon gas and the silane gas introduced into the process chamber 10.

When the silane gas is completely removed by the argon gas purge process, open / close valves 52 and 56 of the DCS gas supply pipe 50 and the WF ₆ gas supply pipe 55 are opened to process the DCS gas and the WF ₆ gas into the process chamber 10. To supply. Then, the DCS gas and the WF ₆ gas react inside the process chamber 10 to deposit a tungsten silicide film on the upper surface of the buffer layer (S130).

Referring to step number S130 of FIG. 3, this will be described in more detail. First, the flow rate of the DCS gas supply pipe 50 flows as much as necessary to deposit the tungsten silicide film by opening the DCS gas supply pipe 50 and then opening the vent valve. Vent the DCS gas to the vent line until When the flow rate required to form the tungsten silicide film flows through the DCS gas supply pipe 50, the valve for closing and opening the opening / closing valve 52 is opened, and the opening / closing valves 56 of the WF ₆ gas supply pipe 55 are also closed. Open to supply the WF ₆ gas to the process chamber 10 with the DCS gas.

As described above, when a small amount of WF ₆ gas is supplied into the process chamber 10 together with the DCS gas, and the inside of the process chamber 10 becomes an atmosphere suitable for depositing a tungsten silicide film (nucleation step in FIG. 3), A tungsten silicide film is deposited on the wafer by supplying a WF ₆ gas in earnest with the DCS gas into the process chamber 10 (bulk step in FIG. 3).

At this time, the DCS gas and the WF ₆ gas are mixed in the portion of the second communication pipe 80 where the DCS gas supply pipe 50 and the WF ₆ gas supply pipe 55 meet through the first connection pipe.

When the tungsten silicide film is deposited on the wafer through the above-described process, the DCS gas is introduced into the process chamber 10 to remove tungsten (W) groups that do not react with the DCS gas from the WF ₆ gas supplied to the process chamber 10. To supply. Subsequently, the process chamber 10 is punctured to completely remove the tungsten group which does not react in the tungsten silicide film deposition process (S140).

Subsequently, the first, second and third argon gas supply pipes 30, 34, 38 are opened to supply argon gas into the process chamber 10, and the pressure of the process chamber 10 in a vacuum state is shown in FIG. 3. For example, it is raised to 1200 Torr (S150).

Here, the reason for injecting the argon gas is that it is difficult to raise the pressure of the process chamber 10 lowered to "0 Torr" by pumping down in the process of removing the tungsten group to 1200 Torr in a short time in the next process by injecting argon gas This is to increase the pressure of the process chamber 10 to 1200 Torr.

In this way, when argon gas is injected to raise the internal pressure of the process chamber 10 so that the next process can proceed, the silane gas supply pipe 40 is opened to supply silane gas into the process chamber 10 to process the chamber 10. After removing the chlorine (Cl) group present in the), the process chamber 10 is pumped in a state in which the open / close valves of all gas supply pipes are closed to complete the deposition process of the tungsten silicide film (S160).

As described above, in the first embodiment of the present invention, after the silane gas is supplied into the process chamber 10 to form a buffer layer on the wafer, the silane gas supply pipe 40 and the process chamber 10 remain. After the silane gas is completely purged with argon gas, DCS gas and WF ₆ gas are supplied to the process chamber 10. Then, since the WF ₆ gas in the vicinity of the second connection pipe 80 is the silane gas and WF ₆ gas is not mixed with the silane gas does not meet the type of cucumber particles are not formed.

Second Embodiment

In the CVD apparatus according to the second embodiment, the silane gas supply pipe is directly connected to the process chamber without connecting the silane gas supply pipe with other gas supply pipes in order to reduce the time taken to proceed with the argon purge process (see S120 in FIG. 3) in the first embodiment. Invention.

The CVD apparatus 200 according to the second embodiment includes a process chamber 210 in which a process of depositing a tungsten silicide film on a wafer is performed by reacting largely supplied reaction gases as shown in FIGS. 4 and 5, and In communication with the chamber 210 is connected to the process chamber 210 through the gas supply system 220 and the vacuum tube 295 for supplying the reaction gas and inert gas, etc. into the process chamber 210 is optimal for proceeding the process It consists of a pump 290 to adjust the pressure inside the process chamber 210 to maintain the state of.

Here, the gas supply system 220 includes three inert gas supply pipes 230, 236 and 238, a silane gas supply pipe 240 for supplying silane gas to form a buffer layer for protecting the polysilicon film formed on the wafer, and an upper surface of the buffer layer. the tungsten silicide DCS DCS gas supply pipe for supplying a gas to form a film 250 and a WF ₆ gas supply pipe 255, and, the cleaning gas is NF ₃ comprises a gas supply pipe 260 that supplies the NF ₃ gas.

Each of the gas supply pipes 230, 234, 238, 240, 250, 255, and 260 includes a plurality of on / off valves for opening and closing each gas supply pipe, a filter 222 for filtering impurities contained in the gas, and a gas required for each process. A gas flow rate control device 224 is installed to control the flow rate of the gas. In FIG. 4, only one on-off valve 232, 236, 239, 242, 252, 256, 262 is directly shown among the plurality of valves installed in each gas supply pipe. As shown in FIG. 1, each gas supply pipe is provided with a filter 222, a gas flow control device 224, and an opening / closing valve 232, 236, 239, 242, 252, 256, 262 and the like.

Preferably, argon gas is introduced into the inert gas supply pipe. Among the three inert gas supply pipes (hereinafter, referred to as "argon gas supply pipes"), the first argon gas supply pipe 230 is provided on the left side of the silane gas supply pipe 240 as shown in FIG. 1, and the second argon gas The supply pipe 234 is installed on the right side of the DCS gas supply pipe 250, and the third argon gas supply pipe 238 is installed between the second argon gas supply pipe 234 and the WF ₆ gas supply pipe 255.

Here, the end portion of the first argon gas supply pipe 230 communicates independently with the side surface of the process chamber.

In addition, unlike the first embodiment, the end 240a of the silane gas supply pipe 240 is also separated from the DCS gas supply pipe 250 and the second argon gas supply pipe 234 to communicate with the process chamber 210 independently. This is to shorten the process time by omitting the argon purge process performed in the first embodiment to exhaust the silane gas remaining between the on-off valve 242 and the process chamber 210, the silane gas supply pipe 240 In this case, the silane gas and the WF ₆ gas are not mixed in the gas supply pipe.

Meanwhile, the silane gas supply pipe 240 communicating with the process chamber 210 is branched into two branch pipes 244 and 246 inside the process chamber 210, as shown in FIG. 5, and the gas in the process chamber 210. One of the two branch tubes 244, 246 is located in the outer region 212 and the other is in the inner region 214 so that the concentration can be constant anywhere.

Preferably, the silane gas supply pipe 210 may be connected to the second argon gas supply pipe 234 through the second argon gas connection pipe 234a as shown in FIG. 7. Since the remaining components in FIG. 7 are the same as the components shown in FIG. 4, detailed descriptions are omitted, and the reference numerals of the remaining components give the same numbers as those of the components shown in FIG. 4.

In addition, ends of the DCS gas supply pipe 250 and the second argon gas supply pipe 234 are connected to each other by the first connecting pipe 270, and the third argon gas supply pipe 238 and the WF ₆ gas supply pipe 255 and Ends of the NF ₃ gas supply pipe 260 are connected to each other by the second connection pipe 280, and the first connection pipe 270 communicates with a predetermined portion of the second connection pipe 280. An end of the second connection pipe 280 is branched into two branch pipes 282 and 284 to communicate with the process chamber 210, and each branch pipe 282 and 284 has gas introduced into the process chamber 210. A needle valve 286 is installed to adjust the amount of.

Although not shown, each gas supply line is connected to the vent line, and a vent valve is installed at a connection portion of each gas supply line and the vent line.

A process of forming a tungsten silicide film on the wafer while preventing the formation of particles using the CVD facility configured as described above will be described below.

The process chamber 210 is made in an atmosphere suitable for forming a buffer layer on the wafer to prevent the thickness of the polysilicon film formed on the wafer from being thinned by the chlorine (Cl) group (S300).

That is, as shown in FIG. 3, the pump is driven to make the process chamber vacuum, and the internal temperature of the process chamber is gradually raised two times to create an atmosphere of the process chamber 210 suitable for forming a buffer layer.

As such, when the atmosphere of the process chamber 210 is established, the silane gas required for forming the buffer layer by opening the on / off valves 242 provided in the silane gas supply pipe 240 in the gas supply system 220 is formed in the process chamber ( 210). Then, the silane gas is reacted in the process chamber 210 to deposit a predetermined thickness on the upper surface of the polysilicon film to form a buffer layer to protect the polysilicon film from the chlorine group (S310).

Here, the supply of the silane gas exhausts the silane gas through the vent line until the flow rate of the silane gas supply pipe 240 flows as necessary to open the vent valve and deposit the buffer layer as shown in step S110 of FIG. 3. Let's do it. When the silane gas having the flow rate required to form the buffer layer flows through the silane gas supply pipe 240, the vent valve is closed and the on / off valve 242 is opened to supply the silane gas into the process chamber 210.

When the buffer layer is formed on the wafer by the reaction of the silane gas, the pump 290 is driven to completely exhaust the silane gas remaining in the process chamber 210 to the outside.

Thereafter, the opening and closing valves 252 and 256 of the DCS gas supply pipe 250 and the WF ₆ gas supply pipe 255 are opened to supply the DCS gas and the WF ₆ gas to the process chamber 210. Then, the DCS gas and the WF ₆ gas react inside the process chamber 210 to deposit a tungsten silicide film on the upper surface of the buffer layer (S320).

Referring to step number S130 of FIG. 3, this will be described in more detail. First, the flow rate of the DCS gas supply pipe 250 flows as much as necessary to deposit the tungsten silicide film by opening the DCS gas supply pipe 250 and then opening the vent valve. Vent the DCS gas to the vent line until When the DCS gas flow rate required to form the tungsten silicide film flows through the DCS gas supply pipe 250, the vent valve is closed, the shutoff valve 242 is opened, and the open / close valves 256 of the WF ₆ gas supply pipe 255 are provided. ) Is also opened to supply the WF ₆ gas to the process chamber 210 together with the DCS gas.

As described above, when a small amount of WF ₆ gas is supplied into the process chamber 210 together with the DCS gas, and the inside of the process chamber 210 becomes an atmosphere suitable for depositing a tungsten silicide film (nucleation step in FIG. 3), The tungsten silicide film is deposited on the wafer by supplying a WF ₆ gas in earnest with the DCS gas into the process chamber 210 (bulk step in FIG. 3).

At this time, the DCS gas and the WF ₆ gas are mixed in the portion of the second communication pipe 280 where the DCS gas supply pipe 250 and the WF ₆ gas supply pipe 255 meet through the first connection pipe 270.

When the tungsten silicide film is deposited on the wafer through the above-described process, the DCS gas is introduced into the process chamber 210 to remove tungsten (W) groups that do not react with the DCS gas from the WF ₆ gas supplied to the process chamber 210. To supply. Thereafter, the process chamber 210 is punctured to completely remove the tungsten group which does not react in the tungsten silicide film deposition process (S330).

Subsequently, the first, second and third argon gas supply pipes 230, 234, and 238 are opened to supply argon gas into the process chamber 210 to increase the vacuum of the process chamber 210 to a predetermined pressure (S340).

Here, the reason for injecting the argon gas is that it is difficult to raise the pressure in the process chamber 210 lowered to "0 Torr" by pumping down in the process of removing the tungsten group in a short time in the next process, so that argon gas is injected. This is to raise the pressure of the process chamber 210 to a desired height.

In this way, when argon gas is injected to increase the internal pressure of the process chamber 210 so that the next process can proceed, the silane gas supply pipe 240 is opened to supply silane gas into the process chamber 210 to process the chamber 210. After removing the chlorine (Cl) group present in the () step to complete the deposition process of the tungsten silicide film by pumping the process chamber 210 in a state in which the closing valves of all the gas supply pipe (S350).

In the second embodiment, as shown in FIG. 4, since the silane gas supply pipe 240 is connected to the process chamber 210 independently without being connected to another gas supply pipe, a WF ₆ gas injected in a process of forming a tungsten silicide film And silane gas do not meet at all in the gas supply line.

Therefore, the argon purge process may not be performed to remove the silane gas remaining in the gas supply pipe after supplying the silane gas to form the buffer layer. Therefore, in the second embodiment, there is an advantage that the processing time for argon purge can be shortened.

As described above, the present invention directly connects the silane gas supply pipe to the process chamber so that the silane gas supplied to protect the polysilicon film is purged with argon gas or the other gas supply pipe and the silane gas supply pipe are not connected.

Then, it is possible to prevent the mixing of the silane gas and the WF ₆ gas supplied immediately after the silane gas supply, there is an effect that can prevent the cucumber-shaped particles formed by the reaction of the WF ₆ gas and silane gas.

Claims (6)

A process chamber for depositing a silicide film on a wafer, a gas supply system for supplying an inert gas, silane gas, DCS gas, and WF ₆ gas, etc. required for depositing the silicide film into the process chamber, and a pump communicating with the process chamber. The process of depositing the silicide film while preventing particle formation in the silicide film deposition apparatus including Supplying silane gas into the process chamber to form a buffer layer protecting the silicon film on the wafer; The inert gas is supplied and the process chamber is pumped to discharge the silane gas remaining from the predetermined vicinity where the silane gas and the WF ₆ gas meet in the gas supply system to the outside of the process chamber. Purging; Mixing the DCS gas and the WF ₆ gas in a predetermined portion of the gas supply system and then supplying the gas into the process chamber to deposit the silicide layer on the protective layer; Supplying and pumping the DCS gas into the process chamber to remove tungsten (W) groups that did not react with the DCS gas in the silicide film deposition step; Supplying an inert gas into the process chamber to raise the pressure of the process chamber in a vacuum state to a predetermined pressure; and Supplying the silane gas into the process chamber to remove chlorine (Cl) groups present in the process chamber. The method of claim 1, wherein the inert gas is an argon gas. A process chamber in which a process of depositing a silicide film on a wafer by reacting the supplied reaction gases is performed; A gas supply system in communication with the process chamber and supplying a reaction gas and an inert gas into the process chamber; A pump that communicates with the process chamber through a vacuum tube and regulates a pressure inside the process chamber to maintain an optimal state for proceeding the process, The gas supply system At least one inert gas supply line; A silane gas supply pipe communicating with the process chamber independently to supply silane gas into the process chamber; A DCS gas supply pipe communicating with the inert gas supply pipe by a first connecting pipe, and supplying a DCS gas required to form the silicide film into the process chamber; Supplying WF ₆ gas necessary to form the silicide film into the interior of the process chamber, and includes a first connection tube communicating with the WF ₆ gas supply line through the second connecting tube, And at least one open / close valve, a filter, and a gas flow control device are installed in each of the inert gas supply pipe, the silane gas supply pipe, the DCS gas supply pipe, and the WF ₆ gas supply pipe. The gas supply system of claim 3, wherein three inert gas supply pipes are installed, and among the three inert gas supply pipes. The first inert gas supply pipe is in communication with the side of the process chamber, The second inert gas supply pipe is in communication with the DCS gas supply pipe by the first connecting pipe, And the third inert gas supply pipe is in communication with the WF ₆ gas supply pipe by the second connection pipe. The method of claim 3, wherein one end of the silane gas supply pipe communicating with the process chamber is branched into two branch pipes so that the concentration of silane gas in the process chamber is constant anywhere. Is at the outer region side of the process chamber and the other branch pipe is located at the inner region side. Opening a silane gas supply pipe communicating with the process chamber independently to supply silane gas into the process chamber to form a vernier layer protecting the silicon film on the wafer; The DCS gas supply pipe and the WF ₆ gas supply pipe are opened to mix the DCS gas and the WF ₆ gas in a connecting tube in which the DCS gas supply pipe and the WF ₆ gas supply pipe communicate with each other, and then supply the inside of the process chamber to the protective layer. Depositing the silicide film on top of the film; Supplying and pumping the DCS gas into the process chamber to remove tungsten (W) groups that did not react with the DCS gas in the silicide film deposition step; Supplying an inert gas into the process chamber to raise the pressure of the process chamber in a vacuum state to a predetermined pressure; and Supplying the silane gas into the process chamber to remove chlorine (Cl) groups present in the process chamber.