JP2009259989A - Vapor deposition device and operation decision method of vapor deposition device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vapor deposition device and an operation decision method of the vapor deposition device, capable of reliably stopping the operation of the device when there is a problem in a sealing mechanism. <P>SOLUTION: After supplying a purge gas between a rotary ring and a sealing member, whether the supply pressure of the purge gas is within a reference range is discriminated (step 104). When the supply pressure is within the reference range, and the displacement amount of the sealing member displaced by the supply of the purge gas is within the reference range, the rotary drive of a rotary shaft by a motor is permitted, and the operation of the vapor deposition device is permitted. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vapor phase growth apparatus and an operation determination method for a vapor phase growth apparatus.

  A sealing mechanism for separating (shielding) the processing atmosphere in the chamber and the atmosphere of the motor that rotates the substrate holding unit is known (for example, see Patent Document 1). According to this sealing mechanism, the sealing member is biased by the spring force against the substrate holding portion rotated by the rotation driving unit. Then, by supplying a high-pressure purge gas between the substrate holding part and the seal member, a minute gap is formed between them. The rotational drive unit is driven while maintaining a non-contact state by the minute gap.

Accordingly, when the purge gas is not supplied, the substrate holding portion and the seal member are in contact with each other, and when the supply pressure of the purge gas is insufficient, a sufficient gap is formed between the substrate holding portion and the seal member. Not. When the rotation drive unit is driven in such a state, the substrate holding unit and the seal member come into contact with each other, and dust or the like is generated. If the generated dust or the like flows into the processing chamber, there is a possibility that the wafer will be adversely affected.
In order to prevent such an adverse effect, a method of permitting rotation driving based on the supply pressure of the purge gas before rotating the rotating shaft using the rotation driving unit is conceivable. Furthermore, a method is conceivable in which the supply pressure is monitored even while the rotation shaft is rotating, and the rotation of the rotation shaft is stopped when the supply pressure decreases.

However, even when the supply pressure of the purge gas satisfies the condition, there may be a case where a sufficient gap cannot be formed between the substrate holding portion and the seal member due to a problem with the seal mechanism. In this case, as described above, the generation of dust or the like is caused, and this dust or the like has a negative effect on the wafer.
JP 2005-321002 A JP 2006-17242 A JP-A-11-265868

  In view of the above problems, an object of the present invention is to provide a vapor phase growth apparatus and an operation determination method for the vapor phase growth apparatus that can reliably stop the operation of the apparatus when there is a problem with the sealing mechanism. .

In order to solve the above-mentioned problem, a first aspect of the present invention is a vapor phase growth apparatus, which includes a substrate holding unit that holds a substrate in a chamber, a rotation driving unit that can rotationally drive the substrate holding unit, A seal member that is biased against the substrate holding portion, and that separates the atmosphere in the chamber and the atmosphere of the rotation drive portion; and a purge gas between the substrate holding portion and the seal member Purge gas supply means for supplying pressure, pressure detection means for detecting the supply pressure of the purge gas, and displacement amount detection means for detecting the displacement amount of the seal member displaced by the supply of the purge gas. .
In the first aspect, not only the supply pressure of the purge gas but also the displacement amount of the seal member that is displaced by the supply of the purge gas is detected. Even when the supply pressure of the purge gas satisfies a predetermined standard, a desired gap may not be ensured between the substrate holding portion and the seal member due to a problem with the seal mechanism. According to the first aspect, since the displacement amount of the seal member correlated with the gap is detected, it can be determined whether there is a problem with the seal mechanism based on the displacement amount. Therefore, when there is a problem with the sealing mechanism, it is possible to stop the rotation of the rotating shaft and stop the operation of the vapor phase growth apparatus.

  In this first aspect, the apparatus further comprises control means for controlling the driving of the rotation drive unit, wherein the control means is provided when the supply pressure is within a reference range and the displacement is within the reference range. It is preferable that the rotation drive unit is allowed to be driven. As a result, when there is a problem with the sealing mechanism and a gap cannot be secured between the substrate holding part and the sealing member, it is possible to prevent the rotation driving part from being permitted and to prevent generation of dust and the like. can do.

  In the first aspect, the control means may rotate the rotation when the supply pressure is out of the reference range or the displacement amount is out of the reference range during driving of the rotary drive unit. It is preferable to stop driving of the driving unit. If a problem occurs in the seal mechanism after the rotation drive unit is driven, the drive of the rotation drive unit can be stopped immediately and generation of dust or the like can be suppressed.

According to a second aspect of the present invention, there is provided a method for determining the operation of a vapor phase growth apparatus having a seal mechanism that separates the atmosphere in the chamber from the atmosphere of the rotation driving unit that rotates the substrate holding unit disposed in the chamber. A step of supplying a purge gas between the substrate holding unit and a seal member of the seal mechanism biased against the substrate holding unit; and after supplying the purge gas, a supply pressure of the purge gas is And allowing the rotation drive unit to be driven when the amount of displacement of the seal member that is within the reference range and is displaced by the supply of the purge gas is within the reference range.
In the second aspect, not only the supply pressure of the purge gas but also the drive of the rotation drive unit is permitted when the displacement amount of the seal member displaced by the supply of the purge gas is within the reference range. Even when the supply pressure of the purge gas satisfies the conditions, a desired gap may not be ensured between the substrate holding portion and the seal member due to a problem with the seal mechanism. According to the second aspect, since the rotation drive unit is allowed to be driven in consideration of the displacement amount of the seal member having a correlation with the gap, if there is a problem with the seal mechanism, the vapor phase growth apparatus can be surely operated. The operation can be stopped.

  In this second aspect, after the drive of the rotary drive unit is permitted, the drive of the rotary drive unit is stopped when the supply pressure is out of the reference range or the displacement amount is out of the reference range. Preferably, the method further includes the step of: If a problem occurs in the seal mechanism after the rotation drive unit is driven, the drive of the rotation drive unit can be stopped immediately and generation of dust or the like can be suppressed.

  FIG. 1 is a diagram for explaining a schematic configuration of a vapor phase growth apparatus 1 according to an embodiment of the present invention. The vapor phase growth apparatus 1 is, for example, a single wafer type epitaxial apparatus. As shown in FIG. 1, the epitaxial apparatus 1 has a chamber 2 as a reaction chamber.

Connected to the upper portion of the chamber 2 is one end of an introduction pipe 3 for introducing a process gas (raw material gas) necessary for vapor phase growth. Although not shown, the other end of the introduction pipe 3 communicates with a gas source via a mass flow controller that is a flow rate controller. Examples of the process gas include hydrogen (H ₂ ) as a carrier gas, silane (SiH ₄ ) as a silicon source, dichlorosilane (SiH ₂ Cl ₂ ), trichlorosilane (SiHCl ₃ ), and diborane as a dopant gas. (B ₂ H ₆ ), phosphine (PH ₃ ), and the like can be given. The process gas may be supplied into the chamber 2 by a shower head.

  One end of the exhaust pipe 4 is connected to the bottom of the chamber 2. The other end of the exhaust pipe 4 communicates with a vacuum pump as the vacuum exhaust means 5. A throttle valve 6 as a pressure control valve is provided near the chamber 2 in the exhaust pipe 4. By controlling the opening degree of the throttle valve 6, the pressure in the chamber 2 can be controlled to the target pressure.

  A holder 8 that holds the wafer 7 rotatably in the horizontal direction is disposed in the chamber 2. The wafer 7 is heated to a desired growth temperature by the out-heater 9a and the in-heater 9b arranged in the holder 8. The holder 8 has a rotating ring 10 at the bottom. A rotating shaft 11 is connected to the rotating ring 10. When the rotary shaft 11 is rotationally driven by a motor that is the rotational drive means 12, the wafer 7 held by the holder 8 rotates. The rotating shaft 11 and the motor 12 are covered with a cover 13.

  The epitaxial apparatus 1 includes a sealing mechanism S for shielding the processing atmosphere in the chamber 2 and the atmosphere of the motor 12 (that is, the atmosphere in the cover 13). As shown in FIG. 2, the seal mechanism S includes an annular seal member 14. FIG. 2 is a view showing the vicinity of the seal mechanism S shown in FIG. The seal member 14 is urged by a spring 15 toward the rotary ring 10 facing the upper surface 14a. The spring 15 is held by a spring holding portion 16. A drive pin 16 b is fitted in the arc-shaped groove 16 a of the spring holding portion 16. When the drive pin 16b is engaged with the recess 14c at the lower end of the seal member 14, the horizontal movement is prohibited while allowing the seal member 14 to move in the vertical direction.

  The outer peripheral portion of the spring holding portion 16 is fixed to the lower end of the annular seal member holding portion 17 by a bolt 23. As a result, the seal member holding portion 17 is disposed outside the seal member 14. The outer peripheral portion of the seal member holding portion 17 is fixed to the upper portion of the cover 13 with a bolt 24. The cover 13 has a flange portion 13a protruding in the outer peripheral direction at the upper end thereof. The flange portion 13 a is fixed to the bottom 2 a of the chamber 2 by a bolt 25.

  A high-pressure purge gas (also referred to as “seal gas”) is ejected from the seal member upper surface 14 a, which is the surface facing the rotating ring bottom surface 10 a, through the purge gas supply passage 19. The other end of the purge gas supply passage 19 communicates with the purge gas source 18 via a pressure gauge 20 that detects the supply pressure of the purge gas and a purge valve 21 that controls the supply of the purge gas. As the purge gas, for example, clean hydrogen gas can be used.

The purge gas supply passage 19 has a supply passage 19a penetrating through the cover 13 in an oblique direction, a supply passage 19b penetrating through the seal member holding portion 17 in the horizontal direction, and an inside of the seal member 14 bent upward. And a supply passage 19c. The communicating portions of the supply passages 19a and 19b are sealed by an O-ring 26. The O-ring 26 is fitted in a groove formed on the outer peripheral surface of the seal member holding portion 17. The communicating portions of the supply passages 19 b and 19 c are sealed by an O-ring 27. The O-ring 27 is disposed so as to be sandwiched between the inner peripheral surface of the seal member holding portion 17 and the outer peripheral surface of the seal member 14. An O-ring 28 is arranged between the inner peripheral surface of the seal member 14 and the spring holding portion 16.
By supplying the high-pressure purge gas from the seal member upper surface 14a in this way, the processing atmosphere and the motor atmosphere can be shielded while the seal member upper surface 14a and the rotary ring 10a are maintained in a non-contact state. .

As shown in FIG. 2, a laser interferometer 22 is disposed below the spring holding portion 16. The laser interferometer 22 can detect the distance to the seal member lower surface 14b, that is, the position of the seal member lower surface 14b, through an opening 16c that further extends the groove 16a of the spring holding portion 16 downward.
Here, the position of the seal member bottom surface 14b has a correlation with the gap between the seal member upper surface 14a and the rotary ring lower surface 10a. Therefore, by obtaining in advance the position of the seal member lower surface 14b when there is no gap (when no purge gas is supplied), the displacement amount of the seal member 14 displaced by the supply of the purge gas can be obtained. A gap between the upper surface 14a and the rotating ring lower surface 10a can be obtained.

  The epitaxial apparatus 1 includes a control unit 30 that performs overall control including apparatus operation determination control (see FIG. 3) of the epitaxial apparatus 1. A vacuum pump 5, a throttle valve 6, heaters 9 a and 9 b, a motor 12, a pressure gauge 20, a purge valve 21 and a laser displacement gauge 22 are connected to the control unit 30.

  According to the epitaxial apparatus 1, the seal member 14 is biased toward the rotating ring 10 by the spring force. Thereby, the processing atmosphere in the chamber 2 and the atmosphere of the motor 12 are shielded. When the motor 12 is driven in this state, the seal member 14 and the rotating ring 10 come into contact with each other to generate dust and the like. By ejecting the purge gas from the seal member surface 14a, a high-pressure purge gas is supplied between the seal member 14 and the rotary ring 10, and a minute gap is formed between the seal member 14 and the rotary ring 10. Since the seal member 14 and the rotary ring 10 are kept in a non-contact state by this minute gap (for example, 10 μm), the rotary shaft 11 can be driven to rotate by the motor 12.

  By the way, the non-contact state between the seal member 14 and the rotary ring 10 can be monitored based on the supply pressure of the purge gas. That is, if the supply pressure of the purge gas is within the reference range, it can be determined that a sufficient gap (for example, 10 μm) is formed between the seal member 14 and the rotary ring 10, and the motor 12 rotates the rotary shaft. Thus, it can be determined that 11 rotational driving is possible.

  However, despite such monitoring, there may be a case where the gap between the two cannot be maintained sufficiently due to the problem of the seal mechanism S. Examples of the problem of the seal mechanism S include individual variations of the spring 15 and adhesion of the seal member 14. If there is such a problem, the seal member 14 and the rotary ring 10 come into contact with each other during the rotation of the rotary shaft 11, and dust or the like is generated. The dust or the like adversely affects the wafer 7. there is a possibility.

  Therefore, in the present embodiment, whether or not the rotation shaft 11 can be rotationally driven by the motor 12 based on the displacement amount of the seal member 14 in addition to the supply pressure of the purge gas, that is, the operation of the epitaxial device 1 is performed. It is determined whether or not it is possible. Hereinafter, specific control will be described.

  FIG. 3 is a flowchart showing an apparatus operation determination control routine executed by the control unit 30 in the present embodiment. According to the routine shown in FIG. 3, it is first determined whether or not there is an operation start request (step 100). In this step 100, it is determined that there is an operation start request for a period from when the wafer 7 is transferred onto the holder 8 to before the motor 12 starts to be driven. If it is determined in step 100 that there is an operation start request, the purge valve 21 is opened to supply purge gas (step 102).

  Next, it is determined whether or not the supply pressure of the purge gas detected by the pressure gauge 20 is within the reference range (step 104). This reference range is the supply pressure of the purge gas necessary for forming a desired gap between the rotary ring 10 and the seal member 14, and is set in advance to, for example, 0.2 MPa to 0.25 MPa. If it is determined in step 104 that the supply pressure is out of the reference range, it is determined that the supply pressure has not reached a supply pressure that can form a desired gap between the rotary ring 10 and the seal member 14. In this case, since this routine is completed, the rotation drive of the rotating shaft 11 by the motor 12 is not permitted.

  On the other hand, if the supply pressure is within the reference range in step 104, it is determined whether or not the displacement amount of the seal member 14 displaced by the supply of the purge gas is within the reference range (step 106). This reference range is a reference range for determining whether or not there is a problem with the seal mechanism S, and is based on the position of the lower surface 14b of the seal member when the purge gas is not supplied as a reference. For example, 10 μm) can be set. If it is determined in step 106 that the displacement amount is out of the reference range, a desired gap is provided between the rotary ring 10 and the seal member 14 even though the purge gas is supplied with a sufficient supply pressure. It is determined that there is a problem with the seal mechanism S. Also in this case, since this routine is ended, the rotation drive of the rotating shaft 11 by the motor 12 is not permitted. By displaying on the display device (display) that there is a problem with the seal mechanism S, it is possible to prompt the device operator to check and / or replace the seal mechanism S.

  If it is determined in step 106 that the amount of displacement is within the reference range, the operation of the epitaxial apparatus 1 is permitted (step 108). In this step 108, the motor 12 is energized, whereby the rotational drive of the rotary shaft 11 is started and the supply of process gas is started. Thereafter, this routine is terminated.

  Thereafter, the supply pressure and the displacement amount are monitored. That is, when the routine shown in FIG. 3 is started again, “NO” is determined in the step 100, and the process proceeds to a step 110. In this step 110, it is determined whether or not the rotating shaft 11 is being driven, that is, whether or not the epitaxial apparatus 1 is in operation. If the epitaxial apparatus 1 is on standby, “NO” is determined in the step 110, and this routine is terminated.

  On the other hand, when it is determined in step 110 that the rotating shaft 11 is being driven, whether or not the supply pressure is within a reference range (for example, 0.2 MPa to 0.25 MPa) as in step 104 above. Is determined (step 112). If the supply pressure is maintained within the reference range, “YES” is determined in this step 112. Thereafter, similarly to step 106, it is determined whether or not the displacement amount is within the reference range (step 114). If the displacement amount is maintained within the reference range, “YES” is determined in the step 114, and then this routine is terminated. Then, the operation of the apparatus is maintained.

  However, after the operation of the apparatus is permitted, the operation of the apparatus is stopped when it is determined that the displacement amount is out of the reference range even though the supply pressure is within the reference range (step 116). In step 116, the energization of the motor 12 is stopped, whereby the rotational drive of the rotary shaft 11 is stopped. Thereafter, this routine is terminated. In this case, by displaying on the display device (display) that the problem of the seal mechanism S has occurred, it is possible to prompt the device operator to check and / or replace the seal mechanism S.

  As described above, in the present embodiment, the supply pressure of the purge gas is detected, and the displacement amount of the seal member 14 that is displaced by the supply of the purge gas is detected by the laser displacement meter 22. From the detection result by the laser displacement meter 22, the displacement amount (movement amount) of the seal member 14 from the reference position, that is, the position of the seal member 14 can be specified. For this reason, the clearance gap formed between the rotating ring 10 and the sealing member 14 can be calculated | required. Then, not only the supply pressure of the purge gas but also the displacement amount of the seal member 14 is taken into consideration, and the operation of the epitaxial device 1 is permitted. That is, if the displacement of the seal member 14 is outside the reference range even though the supply pressure of the purge gas is within the reference range, it can be determined that there is a problem with the seal mechanism S, and the motor 12 Driving of the rotating shaft 11 is prohibited. Therefore, generation of dust or the like due to the problem of the seal mechanism S can be prevented.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, although the distance to the seal member lower surface 14b is detected by the laser displacement meter 22 in the above embodiment, the present invention is not limited to this, and the rotary ring 10 is located in a position facing the seal member 14. A laser displacement meter 22 may be embedded to detect the distance to the rail member upper surface 14a.

It is a figure for demonstrating schematic structure of the vapor phase growth apparatus 1 by embodiment of this invention. It is a figure which expands and shows the vicinity of the seal mechanism S shown in FIG. 4 is a flowchart showing an apparatus operation determination control routine executed by a control unit 30 in the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Epitaxial apparatus 2 Chamber 8 Holder 10 Rotating ring 11 Rotating shaft 12 Motor 14 Seal member 15 Spring 19 Purge gas supply passage 20 Pressure gauge 22 Laser displacement meter 30 Control part

Claims (5)

A substrate holder for holding the substrate in the chamber;
A rotational drive unit capable of rotationally driving the substrate holding unit;
A seal member that is biased against the substrate holding unit, and that separates the atmosphere in the chamber and the atmosphere of the rotation drive unit;
A purge gas supply means for supplying a purge gas between the substrate holder and the seal member;
Supply pressure detecting means for detecting the supply pressure of the purge gas;
A vapor phase growth apparatus comprising: a displacement amount detecting means for detecting a displacement amount of the seal member that is displaced by the supply of the purge gas. The vapor phase growth apparatus according to claim 1,
Further comprising a control means for controlling the drive of the rotation drive unit,
The vapor phase growth apparatus characterized in that the control means permits the rotation drive unit to be driven when the supply pressure is within a reference range and the amount of displacement is within the reference range. The vapor phase growth apparatus according to claim 2,
The control means stops driving the rotation drive unit when the supply pressure is out of the reference range or the displacement amount is out of the reference range during driving of the rotation drive unit. A vapor phase growth apparatus characterized by that. An operation determination method for a vapor phase growth apparatus having a seal mechanism that separates an atmosphere in a chamber and an atmosphere of a rotation driving unit that rotates a substrate holding unit disposed in the chamber,
Supplying a purge gas between the substrate holder and the seal member of the seal mechanism biased against the substrate holder;
After the purge gas is supplied, when the supply pressure of the purge gas is within a reference range, and the displacement amount of the seal member that is displaced by the supply of the purge gas is within the reference range, the rotation drive unit is driven. And a step of permitting the operation of the vapor phase growth apparatus. In the operation judgment method of the vapor phase growth apparatus according to claim 4,
The method further includes a step of stopping the driving of the rotation driving unit when the supply pressure is out of a reference range or the displacement amount is out of the reference range after the driving of the rotation driving unit is permitted. An operation determination method for a vapor phase growth apparatus.