JP4696135B2 - Gate valve and deposition system - Google Patents

Description

  The present invention relates to a gate valve and a film forming system using the same.

2. Description of the Related Art Conventionally, a film forming apparatus including a film forming apparatus that forms a film on a substrate placed in a chamber, and a remote plasma generation apparatus that is disposed on the upper part of the film forming apparatus and activates a cleaning gas to supply the chamber to the chamber. There is a system (see, for example, Patent Document 1). In such a system, when cleaning is repeatedly performed, powder such as aluminum fluoride generated due to fluorine radicals in the activated cleaning gas and anodized aluminum constituting the inner surface of the remote plasma generating device. The body adheres to the inner surface of the remote plasma generator. Therefore, there is a problem that the powder falls during film formation and contaminates the substrate. Therefore, a gate valve for preventing powder from dropping is provided in the pipe between the film forming apparatus and the remote plasma generating apparatus.
JP 2000-323467 A

  In the gate valve described above, an O-ring is provided on the main surface of the valve body that advances and retreats with respect to the piping in order to improve shielding. However, the conventional gate valve has a problem that when the valve body is retracted from the pipe, the O-ring is exposed to the activated cleaning gas and easily deteriorates. Therefore, it is difficult to maintain the shielding property of the gate valve.

  The present invention has been made in order to solve the above-described problems. A gate valve capable of maintaining a shielding property for a long period of time by suppressing deterioration of an O-ring in a valve body, and a component provided with such a gate valve. An object is to provide a membrane system.

  In order to solve the above-mentioned problems, a gate valve according to the present invention is disposed on a film forming apparatus for forming a film on a substrate installed in a chamber and an upper part of the film forming apparatus, and activates a cleaning gas to enter the chamber. A gate valve arranged in a pipe between the remote plasma generator to be supplied, a casing fixed to the pipe, a valve body installed in the casing and capable of advancing and retracting from the pipe; While the O-ring provided on the main surface of the valve body and the cleaning gas activated by the remote plasma generator are being supplied to the chamber, the O-ring is moved to the inner surface of the casing while the valve body is retracted from the pipe. And a valve body control means for pressing.

  This gate valve moves the valve body into the pipe while film formation is being performed on the substrate, thereby generating powder generated due to fluorine radicals and the inner surface material of the remote plasma generator. Blocks falling and prevents contamination of the substrate during film formation. On the other hand, in this gate valve, the O-ring is pressed against the inner surface of the casing while the valve body is retracted from the pipe while the cleaning gas activated by the remote plasma generating apparatus is supplied to the chamber. Thereby, during cleaning, the area where the O-ring is exposed to the activated cleaning gas flowing through the pipe can be reduced. Therefore, the deterioration of the O-ring is suppressed, and the shielding performance of the gate valve can be maintained for a long time even when cleaning is repeatedly executed.

  Moreover, it is preferable that the guard ring is provided in the outer surface of the O-ring in the main surface of the valve body. Thereby, inflow of the activated cleaning gas to the O-ring pressed against the inner surface of the casing can be suppressed. Therefore, the deterioration of the O-ring is further suppressed, and the gate valve can be maintained for a longer time even when cleaning is repeatedly performed.

  The guard ring is preferably formed of polytetrafluoroethylene. Polytetrafluoroethylene is particularly excellent in corrosion resistance against fluorine radicals and the like frequently used as a cleaning gas. Therefore, even when the cleaning is repeatedly executed, the deterioration of the O-ring can be more effectively prevented.

  In addition, while the film formation apparatus is performing film formation on the substrate, the valve body control means advances the valve body into the piping and presses the O-ring against the inner surface of the casing, and the O-ring is pressed against the inner surface. In this case, a gap is preferably formed between the guard ring and the inner surface. When the guard ring hits the inner surface of the casing, the adhesion between the O-ring and the inner surface of the casing is impaired, and the gate valve cannot be sufficiently shielded by the valve body. Therefore, since the gap is formed between the guard ring and the inner surface, the shielding performance of the gate valve can be suitably secured even when the guard ring is provided outside the O-ring.

  Moreover, it is preferable that the protrusion amount of the O-ring protruding from the main surface of the valve body is larger than the protrusion amount of the guard ring protruding from the main surface. If the cleaning is repeatedly performed and the O-ring is pressed against the inner surface of the casing many times, the O-ring may be worn. When the O-ring is worn and the guard ring comes into contact with the inner surface of the casing, the adhesion between the O-ring and the inner surface of the casing is lost, and the gate valve cannot be sufficiently shielded. Therefore, by making the protruding amount of the O-ring larger than the protruding amount of the guard ring, the shielding performance of the gate valve can be maintained for a long time even when the guard ring is provided outside the O-ring.

  Further, it is preferable that the valve body control means advances and retracts the valve body in synchronization with the opening and closing of the supply valve made by the valve control means for controlling the opening and closing of the supply valve for the cleaning gas supplied to the remote plasma generating device. . In this case, the valve element can be advanced and retracted at an optimal timing.

  In addition, a film forming system according to the present invention includes the above-described gate valve. In this film forming system, while the film is being formed on the substrate, the valve body is advanced into the pipe so that the powder generated due to fluorine radicals and the inner surface material of the remote plasma generating device can be obtained. Blocks falling and prevents contamination of the substrate during film formation. On the other hand, in this film forming system, the O-ring is pressed against the inner surface of the casing while the valve body is retracted from the pipe while the cleaning gas activated by the remote plasma generating apparatus is supplied to the chamber. Thereby, during cleaning, the area where the O-ring is exposed to the activated cleaning gas flowing through the pipe can be reduced. Therefore, the deterioration of the O-ring is suppressed, and the shielding performance of the gate valve can be maintained for a long time even when cleaning is repeatedly executed.

  According to the gate valve and the film forming system using the same according to the present invention, the shielding performance of the gate valve can be maintained for a long time by suppressing the deterioration of the O-ring in the valve body. Further, the decomposition / peeling of the O-ring composition accompanying the deterioration of the O-ring can be suppressed, and the particle scattering to the substrate due to the decomposition / peeling can be reduced.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram schematically showing an embodiment of a film forming system to which a gate valve according to the present invention is applied. As shown in FIG. 1, a film forming system 10 connects a CVD (chemical vapor deposition) apparatus (film forming apparatus) 20 for forming a film, a remote plasma generating apparatus 40, and these apparatuses 20 and 40. And a pipe 60.

  The CVD apparatus 20 includes a stage 24 and a face plate 26 inside the chamber 22. The chamber 22 is a metal box container. The interior of the chamber 22 is evacuated in use by an evacuation unit (not shown). The upper surface of the stage 24 is a mounting surface on which the substrate W is installed. The stage 24 is disposed at a substantially central position in the chamber 22 by a support 28.

  The face plate 26 is disposed on the inner wall on the upper surface side of the chamber 22 so as to face the mounting surface of the stage 24. A plurality of inlets (not shown) for introducing a film forming gas and a cleaning gas are formed on the bottom surface of the face plate 26.

  In addition, the CVD apparatus 20 includes a film forming gas supply pipe 30. The film forming gas supply pipe 30 is connected to the side of the pipe 60 on the CVD apparatus 20 side. A film forming gas supply valve 32 is disposed between the CVD apparatus 20 and the film forming gas supply pipe 30.

In the film forming process by the CVD apparatus 20, the film forming gas supply valve 32 is opened, and the film forming gas is supplied from the film forming gas supply pipe 30 to the CVD apparatus 20. The deposition gas, the gas corresponding to the desired thin film composition (e.g., SiO ₂₎ (for example, TEOS and _{O 2,} or SiH ₄ and _{O 2)} are used, is introduced from the inlet of the face plate 26 to the chamber 22 . In the CVD apparatus 20, a thin film is generated by a chemical reaction of a film forming gas on a substrate W heated in advance by a heater (not shown) connected to the stage 24.

The remote plasma generation apparatus 40 is disposed on the upper part of the CVD apparatus 20 and includes cleaning gas supply valves 42 and 44, cleaning gas supply pipes 46 and 48, and a cleaning gas valve control unit (valve control means) 50. Yes. The remote plasma generator 40 is connected to cleaning gas supply pipes 46 and 48 via cleaning gas supply valves 42 and 44. As the cleaning gas, for example, a mixed gas of Ar and NF ₃ is used, Ar is supplied from the cleaning gas supply pipe 46, and NF ₃ is supplied from the cleaning gas supply pipe 48. The cleaning gas valve control unit 50 controls the opening and closing of the cleaning gas supply valves 42 and 44.

  In the cleaning process by the remote plasma generator 40, the cleaning gas supply valves 42 and 44 are opened, and the cleaning gas is supplied from the cleaning gas supply pipes 46 and 48 to the remote plasma generator 40. In the remote plasma generating device 40, the cleaning gas is dissociated and activated by applying energy to the cleaning gas by microwaves or high frequency, and fluorine radicals and the like are generated. Then, the activated cleaning gas containing fluorine radicals or the like is introduced into the chamber 22 of the CVD apparatus 20 from the inlet of the face plate 26, and decomposes substances adhering to the inner surface of the chamber 22 due to the film forming gas. ·Remove.

  The pipe 60 is, for example, a metal cylindrical member. The pipe 60 is disposed substantially vertically between the CVD apparatus 20 and the remote plasma generation apparatus 40.

  By the way, generally, when the cleaning process of the chamber 22 is repeatedly performed, powders generated due to fluorine radicals in the activated cleaning gas and anodized aluminum constituting the inner surface of the remote plasma generator 40 are generated. It adheres to the inner surface of the remote plasma generator 40. Therefore, in the above-described film forming system 10, if the pipe 60 is left open, the powder such as aluminum fluoride attached to the inner surface of the remote plasma generating device 40 is removed in the film forming process. There is a risk of falling from 40 through the pipe 60 and contaminating the substrate W in the chamber 22 of the CVD apparatus 20. Therefore, a gate valve 62 for preventing such powder from dropping is provided at a substantially middle portion of the pipe 60.

  Hereinafter, the gate valve 62 will be described in detail. FIG. 2 is a plan view of the gate valve, and FIG. 3 is a side view showing the gate valve shown in FIG.

  As shown in FIGS. 2 and 3, the gate valve 62 includes a casing 64 that is airtightly fixed to the pipe 60, a mechanism portion 66, a drive shaft 68 connected to the mechanism portion 66, and a tip of the drive shaft 68. And a fixed valve body 70. The substantially rectangular parallelepiped casing 64 includes a first portion 64 a that houses the mechanism portion 66, and a second portion 64 b that houses the mechanism portion 66 and the valve body 70.

  The first and second portions 64a and 64b are integrally formed of metal and have a continuous space inside. Communication holes 72a and 72b for communicating the pipe 60 and the internal space of the casing 64 are formed in the upper surface and the bottom surface of the second portion 64b, respectively.

  The mechanism portion 66 is disposed inside the first portion 64 a and is connected to a valve body control portion (valve body control means) 74 outside the casing 64. The operation of the mechanism unit 66 is controlled by a signal from the valve body control unit 74. The mechanism 66 has a function of moving the drive shaft 68 in the horizontal direction and the vertical direction. As such a mechanism, for example, a single air or the like is used as a power source, and a mechanism for switching the movement direction of the drive shaft 68 by a cam, an air power source in the horizontal direction, and an air power source in the vertical direction are provided. A mechanism or the like can be used.

  The valve body control unit 74 is connected to the cleaning gas valve control unit 50. The valve body control unit 74 controls the operation of the drive shaft 68 based on the opening / closing signal of the cleaning gas supply valve 42 output from the cleaning gas valve control unit 50, and moves the valve body 70 into and out of the pipe 60.

  Next, the valve body 70 will be described. FIG. 4 is a plan view showing a main surface of the valve body, and FIG. 5 is an enlarged view of a main part of the cross section taken along the line VV of the valve body in FIG. As shown in FIG. 4, the valve body 70 includes a disk member 76, an O-ring 78, and a guard ring 80.

  As shown in FIG. 5, a recess 70 b and a recess 70 c are formed on the bottom surface of the disk member 76, that is, the bottom surface 70 a of the valve body 70 so as to be concentric with the disk member 76. The recess 70b and the recess 70c have, for example, a ring shape, and the recess 70c is formed outside the recess 70b.

  The O-ring 78 is formed of a synthetic rubber material such as perfluoroelastomer. The O-ring 78 has a function of sealing the communication hole 72 b in cooperation with the disk member 76 and improving the shielding performance of the gate valve 62.

  The guard ring 80 is made of a material having corrosion resistance against the activated cleaning gas, for example, polytetrafluoroethylene. The guard ring 80 is integrally formed by a portion fitted into the recess 70 c and a flat portion protruding from the bottom surface 70 a of the valve body 70. In addition, although the disk member 76 mentioned above is generally formed with the metal, you may integrally mold with the guard ring 80, for example with polytetrafluoroethylene.

  Further, as shown in FIG. 5, the protruding amount h1 of the O-ring 78 protruding from the bottom surface 70a of the valve body 70 is about 0.3 mm larger than the protruding amount h2 of the guard ring 80 protruding from the bottom surface 70a of the valve body 70. It has become. In the present embodiment, for example, h1 is 0.8 mm and h2 is 0.3 mm, and h1 is about 0.5 mm larger than h2.

  Next, the operation of the gate valve 62 having the above-described configuration will be described. 6 and 7 are cross-sectional views showing the operation of the gate valve.

  In the film forming step, the valve body 70 has advanced into the pipe 60 as shown in FIG. 6A, and the communication hole 72b on the CVD apparatus 20 side in the casing 64 is sealed. The shielding property of the gate valve 62 is ensured by pressing the O-ring 78 around the communication hole 72 b on the inner surface 64 c of the casing 64. In the film forming process, the gate valve 62 shields the pipe 60, so that the powder adhering to the inner surface of the remote plasma generating device 40 is prevented from falling through the pipe 60 and contaminates the substrate W in the chamber 22. Is suppressed.

  Further, as shown in FIG. 5, the O-ring 78 projects larger than the guard ring 80 from the bottom surface 70 a of the valve body 70. Accordingly, there is a gap between the guard ring 80 and the inner surface 64c of the casing 64 in a state where the O-ring 78 is pressed around the communication hole 72b. In the present embodiment, the gap is about 0.3 mm, for example.

  When the film forming gas supply valve 32 is shielded after the film forming process is completed, the supply of the film forming gas to the CVD apparatus 20 is stopped. Next, the substrate W is unloaded from the chamber 22 of the CVD apparatus 20. When the substrate W is unloaded, the cleaning gas valve control unit 50 opens the cleaning gas supply valve 42. As a result, Ar gas is supplied from the cleaning gas supply pipe 46 to the remote plasma generator 40.

  Further, the valve body control unit 74 operates the mechanism unit 66 in synchronization with the opening of the cleaning gas supply valve 42 by a signal from the cleaning gas valve control unit 50. The mechanism part 66 moves the valve body 70 upward as shown in FIG.6 (b). Further, as shown in FIG. 7A, the mechanism portion 66 horizontally moves the valve body 70 toward the mechanism portion 66 side and retracts it from the pipe 60.

  Next, the mechanism part 66 moves the valve body 70 downward as shown in FIG.7 (b). Here, as described above, the O-ring 78 protrudes larger than the guard ring 80 from the bottom surface 70 a of the valve body 70. For this reason, when the valve body 70 moves downward, the O-ring 78 comes into contact with and presses the inner surface 64 c of the casing 64 prior to the guard ring 80. In the state where the O-ring 78 is pressed against the inner surface 64c, a gap exists between the guard ring 80 and the inner surface 64c of the casing 64 as in the case of FIG. In the form, the gap was about 0.3 mm.

After a predetermined time (for example, 3 seconds) has elapsed since the cleaning gas supply valve 42 was opened, the cleaning gas supply valve 44 is opened, and NF ₃ is supplied from the cleaning gas supply pipe 48 to the remote plasma generator 40. As described above, the mixed gas of Ar and NF ₃ is supplied to the remote plasma generating device 40, and the cleaning process is started.

  As described above, the gate valve 62 used in the film forming system 10 moves the valve element 70 into the pipe 60 in the film forming process, thereby allowing the radical plasma and the like in the activated cleaning gas and the remote plasma. The fall of the powder produced | generated inside the remote plasma production | generation apparatus 40 resulting from the anodized aluminum etc. which comprise the inner surface of the production | generation apparatus 40 is blocked, and the contamination with respect to the board | substrate W during film-forming is prevented. On the other hand, in the gate valve 62, the O-ring 78 is attached to the casing 64 while the valve body 70 is retracted from the pipe 60 while the cleaning gas activated by the remote plasma generation device 40 is supplied to the chamber 22. The inner surface 64c is pressed. Thereby, in the cleaning process, the area where the O-ring 78 is exposed to the activated cleaning gas flowing through the pipe 60 can be reduced. Accordingly, the deterioration of the O-ring 78 is suppressed, and the shielding performance of the gate valve 62 can be maintained for a long time even when the cleaning process is repeatedly executed. Furthermore, the decomposition / separation of the composition of the O-ring 78 accompanying the deterioration of the O-ring 78 can be suppressed, and particle scattering to the substrate W due to the decomposition / separation can be reduced.

  In the gate valve 62, a guard ring 80 is provided outside the O-ring 78 on the bottom surface 70 a of the valve body 70. Thereby, inflow of the activated cleaning gas to the O-ring 78 pressed against the inner surface 64c of the casing 64 can be suppressed. Accordingly, the deterioration of the O-ring 78 is further suppressed, and the shielding performance of the gate valve 62 can be maintained for a longer time even when cleaning is repeatedly performed.

  In the gate valve 62, the guard ring 80 is formed of polytetrafluoroethylene. Polytetrafluoroethylene is particularly excellent in corrosion resistance against fluorine radicals and the like frequently used as a cleaning gas. Therefore, even when the cleaning process is repeatedly executed, the deterioration of the O-ring 78 can be more effectively prevented.

  Further, in the gate valve 62, the valve body controller 74 advances the valve body 70 to the pipe 60 and deposits the O-ring 78 on the inner surface 64 c of the casing 64 while the CVD apparatus 20 is performing film formation on the substrate W. In the state where the O-ring 78 is pressed against the inner surface 64c, a gap is formed between the guard ring 80 and the inner surface 64c. When the guard ring 80 hits the inner surface 64c of the casing 64, the adhesion between the O-ring 78 and the inner surface 64c of the casing 64 is impaired, and the shielding performance of the gate valve 62 by the valve body 70 cannot be obtained sufficiently. Accordingly, since the gap is formed between the guard ring 80 and the inner surface 64c, even when the guard ring 80 is provided outside the O-ring 78, the shielding performance of the gate valve 62 can be suitably secured. .

  In the gate valve 62, the protrusion amount h1 of the O-ring 78 protruding from the bottom surface 70a of the valve body 70 is set larger than the protrusion amount h2 of the guard ring 80 protruding from the bottom surface 70a. When the cleaning process is repeatedly performed and the O-ring 78 is pressed against the inner surface 64c of the casing 64 many times, the O-ring 78 may be worn. When the O-ring 78 is worn and the guard ring 80 comes into contact with the inner surface 64c of the casing 64, the adhesion between the O-ring 78 and the inner surface 64c of the casing 64 is lost, and the gate valve 62 is sufficiently shielded. Disappear. Therefore, by making the protrusion amount h1 of the O-ring 78 larger than the protrusion amount h2 of the guard ring 80, even when the guard ring 80 is provided outside the O-ring 78, the shielding performance of the gate valve 62 is further increased. Can be maintained for a long time.

  As described above, the protrusion amount h2 of the guard ring 80 is made larger than the protrusion amount h1 of the O-ring 78. As a result, even in the state of FIG. There are also gaps. It is desirable that this gap be small when the valve body 70 is retracted. However, the area where the O-ring 78 is exposed to the activated cleaning gas is originally reduced by the pressing and is activated by the guard ring 80. In addition, the cleaning gas itself is prevented from flowing into the O-ring 78 side. Therefore, even when the clearance between the guard ring 80 and the casing inner surface 64c is the same when the valve body 70 is advanced and retracted, in other words, when the valve body 70 is advanced and retracted, Even if the pressure of the ring 78 on the casing inner surface 64c is the same, a sufficient deterioration preventing effect of the O-ring 78 can be exhibited. Therefore, it is possible to obtain both the shielding property of the gate valve 62 and the effect of preventing the deterioration of the O-ring 78 against the activated cleaning gas. The structure and driving method of the mechanism portion 66, the control method in the valve body control portion 74, etc. This can contribute to the simplification of the process and, in turn, the cost reduction.

  In the gate valve 62, the valve body control unit 74 advances and retracts the valve body 70 in synchronization with the opening and closing of the cleaning gas supply valve 42 performed by the cleaning gas valve control unit 50. In this case, the valve body 70 can be advanced and retracted at an optimal timing.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. For example, in the above-described embodiment, an example in which the valve body 70 advances and retreats with respect to the communication hole 72b of the casing 64 in the opening / closing operation of the gate valve 62 is shown. You may advance and evacuate.

1 is a diagram schematically showing an embodiment of a film forming system to which a gate valve according to the present invention is applied. It is a top view of a gate valve. FIG. 3 is a side view showing a partially broken gate valve shown in FIG. 2. It is a top view which shows the main surface of a valve body. It is a principal part enlarged view of the VV sectional view in FIG. It is sectional drawing which shows operation | movement of a gate valve. FIG. 7 is a cross-sectional view showing a step subsequent to FIG. 6.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Film-forming system, 20 ... CVD apparatus (film-forming apparatus), 22 ... Chamber, 40 ... Remote plasma generator, 42, 44 ... Cleaning gas supply valve, 50 ... Cleaning gas valve control part (valve control means), 60 ... Piping, 62 ... Gate valve, 64a, 64b ... Casing, 64c ... Inner surface of casing, 70 ... Valve body, 70a ... Bottom surface (main surface) of valve body, 74 ... Valve body control section (valve body control means), 78 ... O-ring, 80 ... guard ring, W ... substrate, h1 ... projection amount of O-ring, h2 ... projection amount of guard ring.

Claims (5)

Disposed piping between the remote plasma generating device is supplied to the chamber disposed click leaning gas at the top to activate the deposition apparatus and the film forming device for forming a film on the substrate to be placed in the chamber A gate valve,
A casing fixed to the piping;
A valve body installed in the casing and capable of advancing and retracting from the pipe;
An O-ring provided on the main surface of the valve body;
Valve body control means for pressing the O-ring against the inner surface of the casing while the valve body is retracted from the pipe while the cleaning gas activated by the remote plasma generating device is supplied to the chamber. It equipped with a door,
In the main surface of the valve body, a guard ring is provided outside the O-ring,
The gate valve characterized in that a protruding amount of the O-ring protruding from the main surface of the valve body is larger than a protruding amount of the guard ring protruding from the main surface . The guard ring, a gate valve according to claim 1, characterized in that it is formed by polytetrafluoroethylene. The valve body control means causes the valve body to advance into the pipe and press the O-ring against the inner surface of the casing while the film formation apparatus performs film formation on the substrate, and the O-ring. in a state but which is pressed against the inner surface, a gate valve according to claim 1 or 2, characterized in that a gap is formed between the guard ring and the inner surface. The valve body control means advances and retracts the valve body in synchronization with opening and closing of the supply valve made by a valve control means for controlling opening and closing of a supply valve for cleaning gas supplied to the remote plasma generation device. The gate valve according to any one of claims 1 to 3 . A film forming system comprising the gate valve according to any one of claims 1 to 4 .

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