JP4922870B2 - Board lift device - Google Patents

Description

  The present invention relates to a substrate lift apparatus provided for delivering a substrate to be processed between a transfer robot having a finger portion supporting a substrate to be processed, such as a silicon wafer, and a substrate stage.

  As this type of substrate lift apparatus, there is known a substrate stage provided with a plurality of lift pins that can move up and down to support a substrate to be processed (see, for example, Patent Document 1). In this case, when the substrate to be processed is transferred from the transfer robot to the substrate stage, the substrate to be processed is transferred to a position immediately above the substrate stage while being supported by the finger portions of the transfer robot, and then the lift pins are raised to increase the target. The processing substrate is supported by being lifted from the finger portion by lift pins. Then, after moving the finger part to the side of the substrate stage, the lift pin is lowered to place the substrate to be processed on the upper surface of the substrate stage. Further, when the processed substrate to be processed is transferred from the substrate stage to the transfer robot, the lift pin is raised and the substrate to be processed is supported by being lifted from the substrate stage by the lift pin. The finger part of the transfer robot is entered from the side. Next, the lift pins are lowered so that the substrate to be processed is received by the finger portions.

  By the way, recently, there is a tendency that the substrate to be processed has a large diameter and a thin wall in order to improve productivity. When such a large-diameter thin substrate to be processed is pushed up from the substrate stage with the lift pins of the conventional example, the outer peripheral portion of the substrate to be processed hangs down. Then, when the finger portion is made to enter under the substrate to be processed, the finger portion may interfere with the outer peripheral portion where the substrate to be processed hangs down, so that the substrate to be processed cannot be successfully delivered to the transfer robot.

In addition, when an electrostatic chuck for attracting and holding the substrate to be processed is provided on the substrate stage, even if the voltage application to the electrostatic chuck is stopped, the charges generated on the electrostatic chuck and the substrate to be processed are difficult to disappear. Therefore, when the lift pins are pushed up, the substrate to be processed may be cracked due to an excessive stress acting on the substrate to be processed due to the adsorption force due to the residual charge.
JP-A-11-221721

  SUMMARY OF THE INVENTION In view of the above, the present invention provides a substrate lift apparatus that can reliably transfer a substrate to be processed between the transfer robot and the substrate stage even if the substrate has a large diameter and a thin wall. That is the issue.

  In order to solve the above-mentioned problems, the present invention provides a substrate lift apparatus provided for delivering a substrate to be processed between a transfer robot having a finger portion supporting a substrate to be processed and an arm having a finger attached to the tip thereof and the substrate stage. A support member that supports the outer periphery of the lower surface of the substrate to be processed is provided so as to be movable up and down with respect to the substrate stage, and the substrate to be processed supported by the support member at the lower end position of the support member is the substrate stage. In a state in which a space through which the finger part can pass is secured under the support member at the rising end position of the support member, and the finger part is located immediately above the substrate stage. A notch is formed in a circumferential direction portion of the support member that matches the robot arm.

  When the substrate to be processed is transferred from the transfer robot to the substrate stage with the substrate lift apparatus of the present invention, the substrate to be processed is transferred to a position immediately above the substrate stage while being supported by the finger portion of the transfer robot. The substrate to be processed is raised to the raised end position and supported by pushing up the substrate to be processed from the finger portion by the support member. The support member is prevented from interfering with the robot arm of the transfer robot when the support member is raised by a notch formed in the support member. Then, after the fingers are retracted to the side of the substrate stage through the space secured under the support member at the rising end position, the support member is lowered to the lower end position, and the substrate to be processed is placed on the upper surface of the substrate stage. Placed on.

  Further, when the processed substrate to be processed is transferred from the substrate stage to the transfer robot, the space secured under the support member after the support member is lifted to the rising end position and the substrate to be processed is pushed up from the substrate stage. The finger part of the transfer robot enters the position directly above the substrate stage. Then, the finger part is raised or the support member is lowered, and the substrate to be processed supported by the support member is received by the finger part.

  Here, since the supporting member supports the outer peripheral portion of the lower surface of the substrate to be processed, even if the substrate to be processed has a large diameter and a thin wall, the substrate to be processed is supported horizontally without causing the outer peripheral portion to sag. Therefore, when the finger portion is made to enter the position immediately above the substrate stage, the finger portion does not interfere with the substrate to be processed. Further, when the finger portion is raised or the support member is lowered, the robot arm and the support member can be prevented from interfering with the notch formed in the support member. As described above, according to the present invention, a substrate to be processed can be reliably transferred between the transfer robot and the substrate stage even if the substrate to be processed has a large diameter and a thin wall.

  By the way, when the substrate stage has an electrostatic chuck, when the support member is pushed up by raising the support member, an unreasonable stress due to the adsorption force due to the residual charge on the portion of the substrate to be processed that matches the notch of the support member. May work. Therefore, in the present invention, the support member is formed in a C-shape in a plan view continuous in the circumferential direction from one end to the other end of the notch, and the outer peripheral portion of the lower surface of the substrate to be processed matches the notch. A sub support member supported by a part is provided so as to be lifted and lowered independently from the support member, and when the substrate to be processed is transferred from the substrate stage to the transfer robot, the sub support member is temporarily separated from the support member. It is preferable that the sub-support member is raised in synchronism, and then only the sub-support member is lowered, and after the sub-support member is lowered, the finger portion is made to enter a position directly above the substrate stage through the space.

  As a result, the substrate to be processed is pushed up from the substrate stage in a state where the outer peripheral portion of the lower surface of the substrate to be processed is supported by the support member and the sub support member over the entire periphery, and the substrate to be processed matches the notch of the support member. It is possible to prevent an unreasonable stress from acting on the substrate portion due to the adsorption force due to the residual stress.

  Since the sub support member is lowered before the finger portion enters the position directly above the substrate stage, the sub support member is used when the substrate to be processed is received by the finger portion by the subsequent raising of the finger portion or the lowering of the support member. Will not interfere with the robot arm.

  In the present invention, it is desirable that the substrate stage is provided with a plurality of lift pins that can be moved up and down to support portions other than the outer peripheral portion of the substrate to be processed. Thus, when the substrate to be processed is pushed up from the substrate stage, portions other than the outer peripheral portion of the substrate to be processed can be pushed up by the lift pins. For this reason, it is possible to prevent an unreasonable stress from acting on the portion other than the outer peripheral portion of the substrate to be processed due to the adsorption force due to the residual charges.

  Referring to FIGS. 1 and 2, reference numeral 1 denotes a substrate stage provided in a processing chamber for performing a predetermined process such as dry etching on a substrate S to be processed which is a silicon wafer. The substrate stage 1 includes a base 2 and an electrostatic chuck 3 provided at the center of the upper surface of the base 2. The electrostatic chuck 3 is configured by arranging electrodes in a predetermined pattern in an insulator such as silicon rubber, and the substrate S to be processed is attracted and held on the substrate stage 1 by applying a voltage to the electrodes of the electrostatic chuck 3. .

  Loading and unloading of the substrate S to be processed with respect to the substrate stage 1 is automatically performed by the transfer robot 4. The transfer robot 4 has a robot arm 5 movable in the horizontal direction and the vertical direction, and supports the substrate S to be processed by a finger portion 6 attached to the tip of the robot arm 5.

  In addition, a substrate lift device is provided for transferring the substrate S to be processed between the transfer robot 4 and the substrate stage 1. The substrate lift device includes a support member 7 that supports the outer peripheral portion of the lower surface of the substrate S to be processed. The support member 7 is provided with a tapered guide portion 7a that rises from a portion that matches the outer peripheral edge of the substrate S to be processed. The substrate S to be processed is attached to the support member 7 while being centered by the guide portion 7a. Supported.

  The support member 7 has a notch 7b in a circumferential portion that coincides with the robot arm 5 in a state where the finger portion of the transfer robot 4 is located immediately above the substrate stage 1, and the other end of the notch 7b is connected to the other end. It is formed in a C-shape in a plan view continuous in the circumferential direction. In addition, a plurality of (for example, three) support rods 8 are vertically provided on the lower surface of the support member 7 so as to be spaced apart from each other in the circumferential direction. It is connected to the drive means 9 for raising and lowering. Accordingly, the support member 7 is moved up and down with respect to the substrate stage 1 by the operation of the driving means 9.

  In addition, the substrate lift apparatus includes a sub-support member 10 that supports the outer peripheral portion of the lower surface of the substrate S to be processed at a portion that matches the notch 7 b of the support member 7. Similar to the support member 7, the sub support member 10 is provided with a tapered guide portion 10 a that rises from a portion that matches the outer peripheral edge of the substrate S to be processed. Further, a support bar 11 is suspended from the lower surface of the sub support member 10, and this support bar 11 penetrates the substrate stage 1 and is connected to a drive means 12 for raising and lowering different from the drive means 9. ing. Thereby, the sub support member 10 is lifted and lowered independently from the support member 7 by the operation of the driving means 12. The raising / lowering strokes of the support member 7 and the sub support member 10 are set to be the same.

  Then, at the lower end position of the support member 7 and the sub support member 10, the substrate S to be processed supported thereon is placed on the upper surface of the substrate stage 1 (electrostatic chuck 3). When the support member 7 is at the rising end position and the sub support member 10 is at the falling end position, the finger portion 6 of the transport robot 4 is horizontally between the lower surface of the support member 7 and the upper surface of the sub support member 10. Space that can pass in the direction is secured.

  The substrate lift apparatus further includes a plurality of (for example, three) lift pins 13 provided on the substrate stage 1, and supports portions other than the outer peripheral portion of the substrate S to be processed by the lift pins. Each lift pin 13 penetrates the substrate stage 1 and is connected to a driving means 9 such as an air cylinder for the support member 7 at the lower end thereof, and the lift pin 13 moves up and down in conjunction with the support member 7 with a slight time difference. Note that a relief groove 6 a for avoiding interference with the lift pin 13 is formed in the finger portion 6 of the transfer robot 4.

  Next, the operation of the substrate lift device of the present embodiment will be described. When the substrate to be processed S is transferred from the transfer robot 4 to the substrate stage 1, as shown in FIG. 1, the substrate to be processed S is supported by the finger portion 6 of the transfer robot 4 and placed at a position directly above the substrate stage 1. Transport.

  Next, as shown in FIG. 3A, the support member 7 and the lift pin 13 are raised to the rising end position, and the substrate S to be processed is pushed up and supported from the finger portion 6 by the support member 7 and the lift pin 13. In this case, the support member 7 is prevented from interfering with the robot arm 5 when the support member 7 is raised by the notch 7 b formed in the support member 7.

  Next, as shown in FIG. 3B, the substrate stage passes through a space (the vertical space between the lower surface of the support member 7 and the upper surface of the sub support member 10) that secures the finger portion 6 below the support member 7. Move to the side of 1. Thereafter, as shown in FIG. 3C, the support member 7 and the lift pins 13 are lowered to the lowered end position, and the substrate S to be processed is placed on the upper surface of the substrate stage 1. Then, a voltage is applied to the electrostatic chuck 3 to attract and hold the substrate to be processed S to the substrate stage 1, and in this state, the substrate to be processed S is subjected to predetermined processing.

  When the substrate S is transferred from the substrate stage 1 to the transfer robot 4 after the processing, the voltage application to the electrostatic chuck 3 is stopped and the support member 7 and the sub-members as shown in FIG. The support member 10 is raised to the rising end position, and the lift pins 13 are also raised to the rising end position with a slight time difference with respect to this rise, and the substrate S to be processed is pushed up from the substrate stage 1. As a result, when the substrate to be processed S is pushed up, an unreasonable stress is applied to the portion other than the outer peripheral portion of the substrate to be processed S or the outer peripheral portion that matches the notch 7b of the support member 7 by the adsorption force due to the residual charge. Can be prevented. Therefore, even if the substrate to be processed S has a large diameter and a thin wall, the substrate to be processed S can be pushed up from the substrate stage 1 without causing cracks.

  Next, the sub-support member 10 is lowered, and then, as shown in FIG. 3 (e), the finger portion 6 enters a position directly above the substrate stage 1 through a space secured under the support member 7. Here, since the lower surface outer peripheral portion of the substrate S to be processed is supported by the support member 7, even the large-diameter thin substrate to be processed S is supported horizontally without causing the outer peripheral portion to sag. As a result, the finger portion 6 does not interfere with the substrate to be processed S when the finger portion 6 enters the position immediately above the substrate stage 1.

  Here, when a portion other than the outer peripheral portion of the substrate to be processed S is not supported by the lift pins 13, the central portion of the substrate to be processed S bends slightly downward, but the amount of bending is slight, and the finger portion 6 is not processed. There is no interference with the substrate S. As a result, the lift pin 13 is connected to the driving means 12 for the sub support member 10, and after the lift pin 13 is lowered together with the sub support member 10, the finger portion 6 can be advanced to a position directly above the substrate stage 1. is there.

  Next, as shown in FIG. 3 (f), the finger portion 6 is raised to a position where it abuts on the lower surface of the substrate S to be processed supported by the support member 7 and the lift pins 13. Thereafter, as shown in FIG. 3G, the support member 7 and the lift pin 13 are lowered to the lowered end position, and the target substrate S is received by the finger portion 6. Then, the substrate to be processed S is unloaded from the processing chamber by the transfer robot 4. In this case, the support member 7 is prevented from interfering with the robot arm 5 when the support member 7 is lowered by the notch 7 b formed in the support member 7.

The cutting side view showing the substrate lift device of the embodiment of the present invention. The top view seen from the upper part of FIG. Explanatory drawing which shows the action | operation of the substrate lift apparatus in this Embodiment.

Explanation of symbols

1 Substrate stage 4 Transfer robot 5 Robot arm
6 Finger part
7 Support member 7b Notch
10 Sub support member 13 Lift pin.
S substrate to be processed,

Claims (2)

A substrate lift apparatus provided for delivering a substrate to be processed between a transfer robot including a robot arm having a finger portion supporting a substrate to be processed attached to a tip and a substrate stage having an electrostatic chuck on an upper surface ,
A support member that supports the outer peripheral portion of the lower surface of the substrate to be processed is provided so as to be movable up and down with respect to the substrate stage. Placed at the ascending end position of the support member, a space through which the finger portion can pass is secured under the support member, and the robot arm is placed in a position directly above the substrate stage. A notch is provided in the circumferential portion of the supporting member that matches ,
The support member is formed in a C shape in a plan view continuous in the circumferential direction from one end to the other end of the notch, and supports the outer peripheral portion of the lower surface of the substrate to be processed with the entire portion matching the notch. A member is provided so as to move up and down independently from the support member, and when the substrate to be processed is transferred from the substrate stage to the transfer robot, the sub support member is temporarily raised in synchronization with the support member, Thereafter, only the sub support member is lowered, and after the sub support member is lowered, the finger portion is caused to enter the position immediately above the substrate stage through the space . The substrate stage, claim 1 Symbol mounting substrate lifting device, characterized in that the vertically movable plurality of lift pins for supporting a portion other than the outer peripheral portion of the substrate is provided.

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