KR102256161B1 - Gas exhausting equipment and method for inhibiting deposition of powder in exhaust pipe for semiconductor production facility - Google Patents

Abstract

The present invention relates to an exhaust device for a semiconductor manufacturing facility and a method for preventing powder deposition in an exhaust pipe by using the same. The exhaust device for a semiconductor manufacturing facility comprises: a vacuum pump for generating pressure to discharge residual gases from a process chamber; a chamber exhaust pipe connected between the process chamber and the vacuum pump; and an exhaust pipe plasma apparatus for processing a gas flowing along the chamber exhaust pipe by using inductively coupled plasma. Therefore, the exhaust device for a semiconductor manufacturing facility prevents powder from being deposited in the exhaust pipe through which the residual gases of the process chamber are discharged.

Description

Exhaust equipment for semiconductor manufacturing facilities and method of preventing powder deposition in exhaust pipes using the same {GAS EXHAUSTING EQUIPMENT AND METHOD FOR INHIBITING DEPOSITION OF POWDER IN EXHAUST PIPE FOR SEMICONDUCTOR PRODUCTION FACILITY}

The present invention relates to a semiconductor manufacturing facility technology, and more particularly, to a technology for preventing powder from being deposited in an exhaust pipe through which residual gas of a process chamber is discharged.

Semiconductor devices are manufactured by repeatedly performing processes such as photolithography, etching, diffusion, and metal deposition on a wafer in a process chamber. During the semiconductor manufacturing process, various process gases are used, and after the process is completed, residual gas exists in the process chamber.Since the residual gas in the process chamber contains toxic substances, it is discharged by a vacuum pump and It is purified by an exhaust gas treatment device. However, there is a problem that the powder is deposited in the exhaust pipe connecting the vacuum pump and the scrubber.

In the case of the TiN process in which titanium nitride (TiN) produced by reacting titanium tetrachloride (TiCl ₄ ) gas and ammonia (NH ₃ ) gas is deposited on a wafer using chemical vapor deposition (CVD), it is deposited in the exhaust pipe, which is a problem. Powders are not only residual TiN powder that is discharged from the wafer without being deposited on the wafer in the TiN process, but also ammonium chloride (NH ₄ Cl) powder and TiCl ₄ ·nNH ₃ powder.

Ammonium chloride (NH _{4 Cl) powder is produced by reacting ammonia (NH 3} ) gas and hydrogen chloride (HCl) gas contained in exhaust gas discharged from the process chamber during the TiN process, and hydrogen chloride (HCl) gas at a specific temperature or higher. And ammonia (NH ₃ ) It is decomposed into gas and exists in a gaseous state, but as the temperature in the exhaust pipe decreases, ammonium chloride (NH ₄ Cl) powder is produced below a certain temperature.

TiCl ₄ nNH _{3 powder is produced by reacting titanium tetrachloride (TiCl 4} ) gas and ammonia (NH ₃ ) gas contained in the exhaust gas discharged from the process chamber during the TiN process, and exists in a gaseous state above a certain temperature. As the temperature in the exhaust pipe decreases, it exists as a powder below a certain temperature.

In order to solve the problem of powder deposition in the exhaust pipe due to ammonium chloride (NH ₄ Cl), by heating the exhaust pipe above a specific temperature using a heating device such as a heating jacket, hydrogen chloride (HCl) gas and ammonia (NH ₃ ) The gas does not react to produce solid ammonium chloride (NH ₄ Cl), and the solid ammonium chloride (NH ₄ Cl) is decomposed into hydrogen chloride (HCl) gas and ammonia (NH ₃ ) gas. The technology to pass through is being used. However, this conventional technology is a fundamental solution to the problem of powder deposition in that the _{ammonium chloride (NH 4} Cl) powder can be easily regenerated because hydrogen chloride (HCl) gas and ammonia (NH ₃ ) gas can easily react. It's hard to be.

Korean Patent Application Publication No. 10-2007-0024806 "Heating Jacket" (2007.03.08.)

An object of the present invention is to provide an exhaust equipment that prevents powder from being deposited in an exhaust pipe through which residual gas is discharged from a process chamber in which a TiN process is performed in a semiconductor manufacturing facility, and a method for preventing powder deposition in an exhaust pipe using the same.

In order to achieve the object of the present invention, according to an aspect of the present invention, an exhaust equipment for discharging residual gas in a process chamber in which a TiN process of depositing TiN generated by reacting _{TiCl 4} gas and NH _{3 gas is performed.} As, a vacuum pump for generating a pressure for discharging the residual gas from the process chamber; A chamber exhaust pipe connected between the process chamber and the vacuum pump; And an exhaust pipe plasma apparatus for processing gas flowing along the chamber exhaust pipe using inductively coupled plasma, wherein the exhaust pipe plasma apparatus includes a reaction chamber installed on the chamber exhaust pipe, and disposed to surround the reaction chamber. A magnetic core, a first coil wound around the magnetic core, an igniter installed in the reaction chamber for plasma ignition, and supplying AC power to the first coil so that radio frequency power is applied to the first coil. A plasma treatment region is formed in the reaction chamber by a thermal reaction of the inductively coupled plasma, and the NH ₄ Cl powder contained in the residual gas discharged from the process chamber is provided with a power source. The reaction is decomposed into hydrogen chloride (HCl) gas and ammonia (NH _{3 ) gas, and TiCl 4} ·nNH ₃ powder contained in the residual gas discharged from the process chamber _{is TiCl 4} by the thermal reaction in the plasma treatment region. It is decomposed into gas and ammonia (NH _{3 ) gas, and the ClF 3} gas injected into the process chamber for cleaning the process chamber after the TiN process reacts with the TiN _{to generate TiF 4} powder, and the process after the cleaning _{A mixture of the ClF 3} gas and the TiF ₄ powder discharged from the chamber is _{converted into a mixed gas of the TiCl 4} gas and the F ₂ gas by the thermal reaction in the plasma treatment region, and an exhaust equipment for a semiconductor manufacturing facility is provided.

In order to achieve the object of the present invention, according to another aspect of the present invention, a TiN process step of performing a TiN process of depositing TiN generated by reacting a _{TiCl 4} gas and an NH _{3 gas in a process chamber is performed;} A first exhaust step in which residual gas in the process chamber after the TiN process is discharged by operation of the vacuum pump through a chamber exhaust pipe connecting between the process chamber and the vacuum pump; A first plasma treatment step in which a first plasma treatment region by inductively coupled plasma is formed in the inductively coupled plasma reactor installed on the chamber exhaust pipe to generate a first thermal reaction; A chamber cleaning step in which TiN powder and organic matter remaining in the process chamber are removed by injecting _{ClF 3} gas into the process chamber after the TiN process in the process chamber, _{and TiF 4 powder is generated;} A second exhaust step in which the residual gas in the process chamber is discharged by operation of the vacuum pump through a chamber exhaust pipe connecting between the process chamber and the vacuum pump after the chamber cleaning step; And a second plasma treatment step in which a second plasma treatment region is formed by inductively coupled plasma in the inductively coupled plasma reactor to generate a second thermal reaction, wherein in the first plasma treatment step, in the first exhaust step _{The NH 4} Cl powder contained in the residual gas of the process chamber discharged by the first thermal reaction is decomposed into hydrogen chloride (HCl) gas and ammonia (NH ₃ ) gas, and the residual gas discharged from the process chamber The included TiCl ₄ ·nNH _{3 powder is decomposed into TiCl 4} gas and ammonia (NH ₃ ) gas by the first thermal reaction, and in the second plasma reaction step, the process chamber discharged by the second exhaust step _{The mixture of the ClF 3} gas and the TiF ₄ powder contained in the residual gas of _{is changed into a mixed gas of the TiCl 4} gas and the F ₂ gas by the second thermal reaction, and a method for preventing powder deposition in an exhaust pipe is provided.

According to the present invention, all the objects of the present invention described above can be achieved. Specifically, in the exhaust gas discharged from the process chamber during the TiN process, ammonium chloride (NH ₄ Cl) powder and TiCl ₄ ·nNH ₃ powder are respectively hydrogen chloride (HCl) gas and ammonia (NH) by thermal reaction by inductively coupled plasma. ₃ ) Gas, TiCl ₄ gas and ammonia (NH ₃ ) gas, and additionally _{, ammonia gas, which is the cause of formation of ammonium chloride (NH 4} Cl) powder and TiCl ₄ ·nNH ₃ powder, is nitrogen by plasma by a DC plasma torch. By decomposition into gas and hydrogen gas, deposition of ammonium chloride powder and TiCl ₄ ·nNH ₃ powder in the exhaust pipe can be fundamentally prevented.

_{In addition, TiF 4} powder and ClF ₃ gas discharged during the cleaning process of the process chamber used in the TiN process are reacted by plasma by the inductively coupled plasma to be treated in the form of _{TiCl 4} gas and fluorine (F _{2) gas.}

1 is a diagram showing a schematic configuration of a semiconductor manufacturing facility equipped with an exhaust equipment according to the present invention.
FIG. 2 is a longitudinal cross-sectional view of a plasma reactor of the exhaust pipe plasma generator provided in the exhaust equipment shown in FIG. 1.
3 is a perspective view illustrating the magnetic core shown in FIG. 2.
4 is a diagram schematically showing the configuration of an ignition system used in the exhaust pipe plasma generating apparatus shown in FIG. 1.
FIG. 5 is a diagram schematically illustrating an action of the plasma reactor in FIG. 2.
6 is a flowchart illustrating a method of preventing powder deposition in an exhaust pipe according to an embodiment of the present invention using the exhaust equipment shown in FIG. 1.

Hereinafter, the configuration and operation of an embodiment of the present invention will be described in detail with reference to the drawings.

1 is a block diagram showing a schematic configuration of a semiconductor manufacturing facility equipped with exhaust equipment according to an embodiment of the present invention. Referring to FIG. 1, a semiconductor manufacturing facility includes a process chamber C in which a TiN process is performed, a scrubber S that processes exhaust gas discharged from the process chamber C, and residual gas in the process chamber C. It includes an exhaust equipment 100 according to an embodiment of the present invention to be discharged to move to the scrubber (S).

In the process chamber C, _{a TiN process is performed in which titanium nitride (TiN) generated by reacting titanium tetrachloride (TiCl 4} ) gas and ammonia (NH ₃ ) gas is deposited on a wafer by using a chemical vapor deposition method (CVD). In the present invention, the process chamber C includes all types of process chambers in which a conventional TiN process is performed. After the TiN process, _{residual gas including TiCl 4} gas, NH ₃ gas, HCl gas, and N ₂ gas and residual TiN powder not deposited on the wafer remains in the process chamber C.

The scrubber S processes the exhaust gas discharged from the process chamber C by the exhaust equipment 100. The scrubber S includes all types of scrubbers commonly used for treating exhaust gases in the field of semiconductor manufacturing equipment technology.

The exhaust equipment 100 discharges residual gas in the process chamber C after the TiN process and moves it to the scrubber S. The exhaust equipment 100 includes a vacuum pump 100a for discharging gas from the process chamber C, a chamber exhaust pipe 100b connecting the process chamber C and the vacuum pump 100a, and a vacuum pump 100a. It is installed on the pump exhaust pipe 100c connecting the scrubber S and the exhaust pipe plasma apparatus 101 for treating exhaust gas flowing along the chamber exhaust pipe 100b using plasma, and the chamber exhaust pipe 100b. A powder collecting trap 170 for collecting powder and a trap plasma device 178 installed in the powder collecting trap 170 to plasma-process the powder collected in the powder collecting trap 170 are provided.

The vacuum pump 100a creates a negative pressure on the side of the process chamber C in order to discharge residual gas from the process chamber C after the TiN process, and includes a configuration of a vacuum pump commonly used in the field of semiconductor manufacturing equipment technology. Detailed description of this will be omitted.

The chamber exhaust pipe 100b connects the exhaust port of the process chamber C and the intake port of the vacuum pump 100a between the process chamber C and the vacuum pump 100a. The residual gas in the process chamber C is discharged as exhaust gas through the chamber exhaust pipe 100b by the negative pressure generated by the vacuum pump 100a.

The pump exhaust pipe 100c connects the discharge port of the vacuum pump 100a and the inlet port of the scrubber S between the vacuum pump 100a and the scrubber S. Exhaust gas discharged from the vacuum pump 100a through the pump exhaust pipe 100c moves to the scrubber S.

The exhaust pipe plasma device 101 processes exhaust gas flowing along the chamber exhaust pipe 100b using inductively coupled plasma. The exhaust pipe plasma apparatus 101 includes an inductively coupled plasma reactor 110 installed on the chamber exhaust pipe 100b and a power supply 180 supplying power to the inductively coupled plasma reactor 110.

The inductively coupled plasma reactor 110 is installed on the chamber exhaust pipe 100b to decompose _{ammonium chloride (NH 4} Cl) powder into hydrogen chloride (HCl) gas and ammonia (NH _{3 ) gas using a thermal reaction, and TiCl 4} · The nNH ₃ powder is decomposed into TiCl ₄ gas and ammonia (NH ₃ ) gas. Additionally, the plasma reactor 110 decomposes ammonia gas, which is a cause of generation of _{ammonium chloride (NH 4} Cl) powder and TiCl ₄ ·nNH _{3 powder, into nitrogen gas and hydrogen gas using a plasma reaction.}

2 shows a schematic configuration of the inductively coupled plasma reactor 110 as a longitudinal cross-sectional view. Referring to FIG. 2, the inductively coupled plasma reactor 110 includes a reaction chamber 120, a magnetic core 130 disposed to surround the reaction chamber 120, an igniter 140 for plasma ignition, and a magnetic core. A first coil (not shown) wound around 130 and receiving power from the power source 180, and a second coil wound around the magnetic core 130 and supplying power to the igniter 140 (not shown). do.

The reaction chamber 120 is a toroidal-shaped chamber, the gas inlet 121, the gas inlet 121 and a gas outlet 123 positioned spaced apart from the gas inlet 121, and A plasma reaction unit 125 connected to the gas discharge unit 123 and in which a plasma reaction occurs is provided.

The gas inlet 121 is in the form of a short tube extending around a straight extension axis A, and the front end of the gas inlet 121 is opened to form an inlet 122 through which the exhaust gas to be treated is introduced.

The gas discharge part 123 is in the form of a short tube located coaxially and spaced apart from the gas inlet part 121 on the extension axis A, and the rear end of the gas discharge part 123 is opened so that the exhaust gas to be treated is discharged. A discharge port 124 is formed.

The plasma reaction unit 125 connects the spaced gas inlet 121 and the gas discharge unit 123, and forms a plasma processing region A therein. The plasma reaction unit 125 includes a first connection pipe portion 126 and a second connection pipe portion 127 that are spaced apart from each other on both sides with an extension axis A interposed therebetween. The first connection pipe portion 126 and the second connection pipe portion 127 extend parallel to the extension axis A and communicate with the gas inlet portion 121 and the gas outlet portion 123. Accordingly, plasma is generated in the plasma reaction unit 125 along the annular discharge loop R as shown by the broken line. The exhaust gas introduced through the gas inlet 122 is treated by the plasma generated in the plasma reaction unit 125 and then discharged through the gas outlet 124.

In this embodiment, the reaction chamber 120 includes the entire gas inlet 121 and a part of the first connection pipe 126 connected to the gas inlet 121 and a part of the second connection pipe 127. A second chamber member including a first chamber member 120a, a part of the first connection pipe part 126 connected to the gas discharge part 123 and the gas discharge part 123, and a part of the second connection pipe part 127 Although (120b) is described as being configured to be combined, the present invention is not limited thereto.

The magnetic core 130 is disposed to surround the reaction chamber 120. In this embodiment, the magnetic core 130 will be described as being a ferrite core generally used in an inductively coupled plasma generator. 3 shows the magnetic core 130 as a perspective view. 2 and 3, the magnetic core 130 has an annular ring portion 131 surrounding the plasma reaction portion 125 of the reaction chamber 120 from the outside, and an inner region of the ring portion 131. It has a connecting portion 135 that crosses.

The ring portion 131 has a rectangular ring shape and is disposed at right angles to the extension axis A to surround the plasma reaction portion 125 of the reaction chamber 120 from the outside. The rectangular ring portion 131 has two long side portions 132a and 132b facing each other, and two short side portions 133a and 133b facing each other.

The connection part 135 extends in a straight line to connect between the two opposite long side parts 132a and 132b of the ring part 131. Both ends of the connection part 135 are connected to the center of each of the two long side parts 132a and 132b. The connection part 135 is disposed to pass through the gap 128 formed between the first connection pipe part 126 and the second connection pipe part 127 of the reaction chamber 120. The inner area of the ring part 131 is separated into a first through hole 136 and a second through hole 137 by the connection part 135, and the first through hole 136 is a first through hole of the reaction chamber 120. The connection pipe part 126 passes and the second connection pipe part 127 of the reaction chamber 120 passes through the second through hole 137. Accordingly, the magnetic core 130 is formed to surround the first connection pipe portion 126 and the second connection pipe portion 127 of the reaction chamber 120 from the outside, respectively.

The igniter 140 ignites the plasma by receiving high voltage power from the outside. In this embodiment, the igniter 140 is described as being positioned adjacent to the gas inlet 121 in the plasma reaction unit 125 of the reaction chamber 120, but the present invention is not limited thereto.

4 shows a first coil and a second coil wound around the magnetic core 130.

Referring to FIG. 4, the first coil 150 is wound around the first long side portion 132a of the magnetic core 130 and is connected to the power source 180. The first coil 150 receives AC power of a radio frequency through the power source 180 to form an induced magnetic flux in the magnetic core 130. An induced electric field is generated by the induced magnetic flux formed in the magnetic core 130, and plasma is formed by the generated induced electric field. In the present embodiment, it is described that the first coil 150 is wound on the magnetic core 130 twice, but the present invention is not limited thereto.

The second coil 160 is wound separately from the first coil 150 on the second long side portion 132b of the magnetic core 130 and is connected to the igniter 140 through a switch circuit (relay) 190. Induced electromotive force is generated in the second coil 160 to supply power to the igniter 140. That is, the first coil 150, the second coil 160, and the magnetic core 130 function as a transformer, so that a high voltage for the operation of the igniter 140 is formed in the second coil 160 and is output. . To this end, the second coil 160 is wound on the magnetic core 130 with a number of turns greater than the number of turns of the first coil 150, and in this embodiment, it will be described as being wound six times.

The power source 180 applies AC power of a radio frequency to the first coil 150 to generate inductively coupled plasma. In this embodiment, the first coil 150, the second coil 160, and the magnetic core 130 function as a transformer. That is, the first coil 150, the second coil 160, and the magnetic core 130 serve as a primary coil, a secondary coil, and an iron core in a transformer. By making the number of turns of the second coil 160 larger than the number of turns of the first coil 150, it is possible to apply a boosted high voltage power to the igniter 140.

A plasma processing region A in which a thermal reaction and a plasma reaction with respect to exhaust gas occur is formed in the plasma reaction unit 125. The temperature of the plasma treatment area (A) is preferably maintained at 250° C. or higher in consideration of _{TiCl 4} ·nNH ₃ powder generated at a temperature of about 250° C. or less, _{and ammonium chloride (NH 4} Cl) generated at about 338° C. If more powder is considered, it is most preferable to maintain at least 350°C. _{That is, TiCl 4} ·nNH ₃ powder is generated by combining _{TiCl 4} gas and ammonia (NH ₃ ) gas at a temperature of about 250° C. or lower, _{so the production of TiCl 4} ·nNH ₃ powder can be suppressed by maintaining the temperature above 250° C. . In addition, since ammonium chloride (NH ₄ Cl) powder vaporizes at a temperature of about 338°C or higher _{and decomposes into hydrogen chloride (HCl) gas and ammonia (NH 3 ) gas, ammonium chloride (NH 4} Cl) powder is generated when maintained at 350°C or higher. This can be suppressed, and in this case, the formation of _{TiCl 4 ·nNH 3} powder can also be suppressed. In this embodiment, it will be described that the temperature of the plasma processing region A is maintained at a temperature of 200°C to 500°C.

5 is a diagram schematically explaining the operation of the exhaust pipe plasma device 101. 5, hydrogen chloride (HCl) gas, ammonia (NH ₃ ) gas, nitrogen (N ₂ ) gas, TiN powder, and TiCl ₄ gas contained in the exhaust gas discharged from the process chamber C are plasma reaction units ( It passes through the plasma processing region A formed inside 125 of FIG. 2. Hydrogen chloride (HCl) gas, nitrogen (N ₂ ) gas, and TiCl ₄ gas pass through the plasma treatment region A without change, and are prevented from thermal reaction in the plasma treatment region A maintained at a temperature of 200°C to 500°C. By this, ammonium chloride (NH ₄ Cl) powder is decomposed into hydrogen chloride (HCl) gas and ammonia (NH ₃ ) gas, and TiCl ₄ ·nNH ₃ powder is _{decomposed into TiCl 4} gas and ammonia (NH ₃ ) gas.

Additionally, ammonia (NH ₃ ) gas is decomposed into _{nitrogen (N 2} ) gas and hydrogen (H ₂ ) gas by plasma reaction in the plasma treatment area (A) _{(2NH 3} (g) → N ₂ (g) + 3H ₂₎ (g)) may be. _{In this case, the ammonia (NH 3} ) gas does not exist after the exhaust gas passes through the plasma treatment region A in the chamber exhaust pipe 120, so that the powder deposition in the chamber exhaust pipe 120 and the pump exhaust pipe 130 The formation of ammonium chloride (NH ₄ Cl) powder and TiCl ₄ ·nNH ₃ powder, which are the main causes, can be fundamentally prevented. _{To generate ammonia (NH 3} ) gas by reacting nitrogen (N ₂ ) gas and hydrogen (H ₂ ) gas, a catalyst is used in a high temperature and high pressure environment (e.g., Fe _x O _{y at 530°C and 290 atm).} Because it must be a catalyst), it is practically impossible to generate _{ammonia (NH 3 ) gas by reacting nitrogen (N 2} ) gas and hydrogen (H ₂ ) gas in the chamber exhaust pipe 120 and the pump exhaust pipe 130. In addition, the TiN powder passes through the plasma treatment region A in the form of a powder.

The powder collecting trap 170 is installed downstream of the plasma treatment region A on the chamber exhaust pipe 100b to collect powder including TiN powder, and prevents the powder from flowing into the vacuum pump 100c. As the powder collecting trap 170 may be a commonly used one (eg, a particle collecting device described in Patent No. 10-1480237), a detailed description thereof will be omitted. In the present embodiment, it is described that the powder collecting trap 170 is installed to be located downstream of the plasma processing area A, but unlike this, it may be installed so as to be located upstream of the plasma processing area A, and the plasma processing area A ) May be provided so as to be located both upstream and downstream, and this is also within the scope of the present invention.

The trap plasma device 178 is installed in the powder collecting trap 170 to remove the powder collected by the powder collecting trap 170 by plasma treatment. In this embodiment, the trap plasma device 178 is described as having a configuration using a DC plasma torch, but the present invention is not limited thereto.

6 is a flowchart illustrating a method of preventing powder deposition in an exhaust pipe according to an embodiment of the present invention using the exhaust equipment shown in FIG. 1. 6, the method for preventing powder deposition in the exhaust pipe according to an embodiment of the present invention includes a TiN process step (S10) in which a TiN process is performed in a process chamber (C of FIG. 1), and a TiN process step (S10). After the TiN process by the first exhaust step (S20) of exhausting the residual gas in the process chamber (C in FIG. 1) by operating the vacuum pump (100a in FIG. 1), the exhaust pipe plasma device during the first exhaust step (S20) During the first plasma treatment step (S30) and the first exhaust step (S20) of generating a thermal reaction and a plasma reaction on the chamber exhaust pipe (100b of FIG. 1) by operating (101 in FIG. 1), a powder collecting trap (FIG. The first collection step (S40) of collecting powder from the exhaust gas flowing through the chamber exhaust pipe (100b of FIG. 1) using 170 of 1) and the chamber cleaning in which cleaning of the process chamber (C of FIG. 1) is performed. After cleaning the chamber by step S50 and the chamber cleaning step S50, the residual gas in the process chamber (C in FIG. 1) is exhausted by operating a vacuum pump (100a in FIG. 1) (S60). ), and a second plasma processing step (S70) of generating a thermal reaction and a plasma reaction on the chamber exhaust pipe (100b of FIG. 1) by operating the exhaust pipe plasma device (101 in FIG. 1) during the execution of the second exhaust step (S60), and , Including a second collecting step (S80) of collecting powder from exhaust gas flowing through the chamber exhaust pipe (100b of Fig. 1) using a powder collecting trap (170 in Fig. 1) while performing the second exhaust step (S60). .

_{In the TiN process step (S10), titanium nitride (TiN) generated by reacting titanium tetrachloride (TiCl 4} ) gas and ammonia (NH ₃ ) gas in a process chamber (C in FIG. 1) is used by chemical vapor deposition (CVD). Conventional TiN processes, such as depositing on a wafer, are performed. _{By the TiN process, residual gas including TiCl 4} gas, NH ₃ gas, HCl gas, and N ₂ gas, which is not deposited on the wafer, remains in the process chamber (C of FIG. 1 ). After the TiN process in the process chamber (C in FIG. 1) is completed, the first exhaust step S20 is performed.

In the first exhaust step (S20), the vacuum pump (110 in FIG. 1) is operated so that the residual gas in the idle chamber (C in FIG. 1) after the TiN process is discharged as exhaust gas through the chamber exhaust pipe 100b and the pump exhaust pipe 100c. Is discharged. In a process in which the first exhaust step S20 is performed, the first plasma treatment step S30 and the first collection step S40 are performed together.

The first plasma treatment step S30 is performed together with the first exhaust step S20. In the first plasma treatment step (S30), the exhaust pipe plasma device (101 in FIG. 1) is operated to generate a thermal reaction and a plasma reaction in the inductively coupled plasma reactor (110 in FIG. 1) installed on the chamber exhaust pipe (100b in FIG. 1). Thus, the first plasma processing region A as shown in FIGS. 2 and 3 is formed. _{In the first plasma treatment step (S30), the ammonium chloride (NH 4} Cl) powder is converted into hydrogen chloride (HCl) gas and ammonia (NH ₃ ) by a thermal reaction in the plasma treatment region (A) maintained at a temperature of 200°C to 500°C. ) Gas, and TiCl ₄ ·nNH ₃ powder is _{decomposed into TiCl 4} gas and ammonia (NH ₃ ) gas. Additionally, ammonia (NH ₃ ) gas is decomposed into _{nitrogen (N 2} ) gas and hydrogen (H ₂ ) gas by plasma reaction in the plasma treatment area (A) _{(2NH 3} (g) → N ₂ (g) + 3H ₂₎ (g)). Therefore, after the exhaust gas passes through the plasma treatment region A in the chamber exhaust pipe 120, ammonia (NH ₃ ) gas does not exist, so that the powder deposition in the chamber exhaust pipe 120 and the pump exhaust pipe 130 The formation of ammonium chloride (NH ₄ Cl) powder and TiCl ₄ ·nNH ₃ powder, which are the main causes, can be fundamentally prevented.

The first collection step (S40) is performed together with the first plasma treatment step (S30) while the first exhaust step (S20) is performed. In the first collecting step (S40), powder such as TiN is collected from the exhaust gas flowing through the chamber exhaust pipe (100b of FIG. 1) using a powder collecting trap (170 in FIG. 1).

In the chamber cleaning step (S50), ClF ₃ gas is injected into the process chamber (C of FIG. 1) to remove TiN powder and organic matter remaining in the process chamber (C of FIG. 1) after the TiN process. _{The ClF 3} gas injected in the chamber cleaning step S50 is combined with TiN to generate _{TiF 4 powder.} After cleaning the chamber by the chamber cleaning step (S50), _{residual gas including ClF 3} gas, TiF ₄ powder, and unremoved TiN powder remains in the process chamber (C of FIG. 1 ). After the chamber cleaning step S50 is completed, the second exhaust step S60 is performed.

In the second exhaust step (S60), the vacuum pump (100a in FIG. 1) is operated so that the residual gas in the process chamber (C in FIG. 1) after the chamber cleaning step (S50) is removed from the chamber exhaust pipe (100b in FIG. 1) and the pump exhaust pipe ( It is discharged as exhaust gas through 100c of FIG. 1. In the process of performing the second exhausting step S60, the second plasma processing step S70 and the second collecting step S80 are performed together.

The second plasma processing step S70 is performed together while the second exhaust step S60 is performed. In the second plasma treatment step (S70), the exhaust pipe plasma device (101 in FIG. 1) is operated, so that the thermal reaction and plasma reaction are performed in the inductively coupled plasma reactor (110 in FIG. 1) installed on the chamber exhaust pipe (100b in FIG. 1). And a second plasma processing region A as shown in FIG. 2 is formed. In the second plasma treatment step (S70), _{the mixture of TiF 4} powder and ClF _{3 gas contained in the exhaust gas is changed into a mixture gas of TiCl 4} gas and F ₂ gas by plasma reaction in the second plasma treatment region (A). (TiF ₄ (s) + 4ClF ₃ (g) → TiCl ₄ (g) + 8F ₂ (g)) and passes through the second plasma treatment area A.

The second collection step S80 is performed together with the second plasma treatment step S70 while the second exhaust step S60 is performed. In the second collection step (S70), powder such as TiN is collected from exhaust gas flowing through the chamber exhaust pipe (100b of FIG. 1) using a powder collection trap (170 in FIG. 1).

In the above embodiment, a case where the present invention is applied to the TiN process has been described, but the present invention is not limited thereto. For example, in the process chamber C of a semiconductor manufacturing facility as shown in FIG. 1, a hexachloride silane (Si ₂ Cl ₆ ) gas and ammonia (NH ₃ ) gas react to produce ammonium chloride (NH ₄ Cl). ) It can also be applied in the case of a process in which powder is generated. In a semiconductor manufacturing process, as a process in which a hexachloride silane (Si ₂ Cl ₆ ) gas and ammonia (NH ₃ ) gas are used, for example, BTBAS [Bis (Tertiary- ButylAmino)Silane) and TiCl ₄ are used to form a TiSiN diffusion barrier, and a process of depositing by adding _{ammonia (NH 3} ) gas and silicon hexachloride (Si ₂ Cl _{6) to suppress the carbon content in the thin film (Public Patent} There is a process described in No. 10-2004-0050802). In processes using NH ₃ and Si ₂ Cl ₆ in the manner as described in the TiN process above by the exhaust device 100 as shown in NH ₄ Cl powder is 1 also resulting from the reaction of NH ₃ and Si ₂ Cl ₆ It can be handled.

In the _{process of using NH 3} and Si ₂ Cl ₆ , the method for preventing powder deposition in an exhaust pipe according to another embodiment of the present invention using the exhaust equipment shown in FIG. 1 is, in the process chamber (C in FIG. 1 ), NH ₃ and Si ₂ A chamber process step in which a process using Cl ₆ is performed, an exhaust step of evacuating residual gas in the process chamber (C in FIG. 1) after the process in the chamber by the chamber process step by operating a vacuum pump (100a in FIG. 1) and And a plasma treatment step of generating a thermal reaction and a plasma reaction on the chamber exhaust pipe (100b of FIG. 1) by operating the exhaust pipe plasma apparatus (101 in FIG. 1) while performing the exhaust step. Since the plasma processing step is performed in a substantially the same manner as the first plasma processing step S30 shown in FIG. 5, a detailed description thereof will be omitted.

Although the present invention has been described through the above embodiments, the present invention is not limited thereto. The above embodiments may be modified or changed without departing from the spirit and scope of the present invention, and those skilled in the art will recognize that such modifications and changes also belong to the present invention.

100: exhaust equipment 100a: vacuum pump
100b: chamber exhaust pipe 100c: pump exhaust pipe
101: exhaust pipe plasma device 110: inductively coupled plasma reactor
120: reaction chamber 130: magnetic core
140: igniter 150: first coil
160: second coil 170: powder collecting trap
178: trap plasma device 180: power

Claims (11)

As an exhaust equipment that discharges residual gas in the process chamber where the TiN process is performed to deposit TiN generated by reacting TiCl ₄ gas and NH _{3 gas,}
A vacuum pump generating pressure for discharging the residual gas from the process chamber;
A chamber exhaust pipe connected between the process chamber and the vacuum pump; And
An exhaust pipe plasma apparatus for treating gas flowing along the chamber exhaust pipe using inductively coupled plasma,
The exhaust pipe plasma apparatus includes a reaction chamber installed on the chamber exhaust pipe, a magnetic core disposed to surround the reaction chamber, a first coil wound around the magnetic core, and installed in the reaction chamber for plasma ignition. An igniter, and a power supply for supplying AC power to the first coil so that radio frequency power is applied to the first coil,
A plasma processing region is formed in the reaction chamber by a thermal reaction of the inductively coupled plasma,
_{NH 4} Cl powder contained in the residual gas discharged from the process chamber is decomposed into hydrogen chloride (HCl) gas and ammonia (NH _{3) gas by the thermal reaction in the plasma treatment region,
TiCl 4} · nNH ₃ powder contained in the residual gas discharged from the process chamber is decomposed into _{TiCl 4} gas and ammonia (NH ₃ ) gas by the thermal reaction in the plasma treatment region,
_{After the TiN process, the ClF 3} gas injected into the process chamber for cleaning the process chamber reacts with the TiN to generate _{TiF 4 powder,
The mixture of the ClF 3} gas and the TiF ₄ powder discharged from the process chamber after the cleaning is changed into a mixed gas of _{TiCl 4} gas and F ₂ gas by the thermal reaction in the plasma treatment region,
Exhaust equipment for semiconductor manufacturing facilities. As an exhaust equipment that discharges residual gas in the process chamber in which the process using NH ₃ and Si ₂ Cl _{6 is performed,}
A vacuum pump generating pressure for discharging the residual gas from the process chamber;
A chamber exhaust pipe connected between the process chamber and the vacuum pump; And
An exhaust pipe plasma apparatus for treating gas flowing along the chamber exhaust pipe using inductively coupled plasma,
The exhaust pipe plasma apparatus includes a reaction chamber installed on the chamber exhaust pipe, a magnetic core disposed to surround the reaction chamber, a first coil wound around the magnetic core, and installed in the reaction chamber for plasma ignition. An igniter, a second coil wound separately from the first coil on the magnetic core and connected to the igniter, and a power supply for supplying AC power to the first coil so that radio frequency power is applied to the first coil. And
In the reaction chamber, a plasma processing region is formed by a thermal reaction of the inductively coupled plasma,
_{NH 4} Cl powder contained in the residual gas discharged from the process chamber is decomposed into hydrogen chloride (HCl) gas and ammonia (NH _{3) gas by the thermal reaction in the plasma treatment region,}
Since the number of turns of the second coil is larger than the number of turns of the first coil, AC power greater than the voltage of AC power applied to the first coil is generated in the second coil and supplied to the igniter,
Exhaust equipment for semiconductor manufacturing facilities. The method according to claim 1,
The exhaust pipe plasma apparatus further includes a second coil wound on the magnetic core separated from the first coil and connected to the igniter,
Since the number of turns of the second coil is larger than the number of turns of the first coil, AC power greater than the voltage of AC power applied to the first coil is generated in the second coil and supplied to the igniter,
Exhaust equipment for semiconductor manufacturing facilities. The method according to claim 2 or 3,
The magnetic core has a ring portion extending in an annular shape,
The first coil and the second coil are located opposite to each other in the ring portion,
Exhaust equipment for semiconductor manufacturing facilities. The method according to claim 1 or 2,
The reaction chamber has a plasma reaction unit forming the plasma processing region therein,
The plasma reaction unit is arranged side by side in a spaced state and has two connection pipe portions through which gas passes, respectively,
The magnetic core has a ring portion surrounding the two connecting pipe portions together, and a connecting portion positioned in a gap formed between the two connecting pipe portions and passing through the inner region of the ring portion,
Exhaust equipment for semiconductor manufacturing facilities. The method of claim 5,
The two connecting pipe portions are connected at the front end and the rear end, respectively, so that plasma is generated along the discharge loop formed in an annular shape in the plasma reaction unit,
Exhaust equipment for semiconductor manufacturing facilities. The method according to claim 1 or 2,
Further comprising a powder collecting trap installed on the chamber exhaust pipe to collect the powder,
Exhaust equipment for semiconductor manufacturing facilities. A TiN process step of performing a TiN process of depositing TiN generated by reacting a _{TiCl 4} gas and an NH ₃ gas in a process chamber;
A first exhaust step in which residual gas in the process chamber after the TiN process is discharged by operation of the vacuum pump through a chamber exhaust pipe connecting between the process chamber and the vacuum pump;
A first plasma treatment step in which a first plasma treatment region by inductively coupled plasma is formed in the inductively coupled plasma reactor installed on the chamber exhaust pipe to generate a first thermal reaction;
A chamber cleaning step in which TiN powder and organic matter remaining in the process chamber are removed by injecting _{ClF 3} gas into the process chamber after the TiN process in the process chamber, _{and TiF 4 powder is generated;}
A second exhaust step in which the residual gas in the process chamber is discharged by operation of the vacuum pump through a chamber exhaust pipe connecting between the process chamber and the vacuum pump after the chamber cleaning step; And
And a second plasma treatment step in which a second plasma treatment region is formed by inductively coupled plasma in the inductively coupled plasma reactor to generate a second thermal reaction,
_{In the first plasma treatment step, the NH 4} Cl powder contained in the residual gas of the process chamber discharged by the first exhaust step is hydrogen chloride (HCl) gas and ammonia (NH ₃ ) gas by the first thermal reaction. _{TiCl 4} ·nNH ₃ powder contained in the residual gas discharged from the process chamber is decomposed into _{TiCl 4} gas and ammonia (NH ₃ ) gas by the first thermal reaction,
_{In the second plasma reaction step, the mixture of the ClF 3} gas and the TiF ₄ powder contained in the residual gas of the process chamber discharged by the second exhaust step _{is TiCl 4} gas and F by the second thermal reaction. ₂ changes to a gas mixture,
How to prevent powder deposition in the exhaust pipe. The method of claim 8,
Further comprising a first collecting step of collecting the powder contained in the residual gas of the process chamber discharged by the first exhaust step using a powder collecting trap installed on the chamber exhaust pipe,
How to prevent powder deposition in the exhaust pipe. The method of claim 8,
Further comprising a second collecting step of collecting the powder contained in the residual gas of the process chamber discharged by the second exhaust step using a powder collecting trap installed on the chamber exhaust pipe,
How to prevent powder deposition in the exhaust pipe. delete

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