JP2005039285A - Vacuum processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the processing capability of a vacuum processor by shortening the transportation time and the carry-in/out time of an object to be processed. <P>SOLUTION: A load-lock mechanism is arranged in a vacuum container. A holding mechanism arranged in the vacuum container holds the object to be processed, and moves the object from a processing position to a transferring position and vice versa. When the holding mechanism holds the object to be processed in the transferring position, inner arms can exchange the object to be processed in the transferring position with the object to be processed held by the load-lock mechanism. The inner arms include a first arm and a second arm which can turn mutually independently. The first arm and the second arm are held mutually in different positions in the directions of their turning shafts, and turning of the first arm moves the object to be processed from the transferring position to the first load-lock mechanism, and simultaneously turns the second arm in the reverse direction, moving the other object to be processed from the load-lock mechanism to the transferring position. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vacuum processing apparatus, and more particularly to a vacuum processing apparatus having a load lock mechanism for carrying in / out a processing object between the inside and outside of the vacuum container.

  A conventional wafer loading / unloading method will be described taking an ion implantation apparatus as an example. Patent Document 1 discloses an ion implantation apparatus having a vacuum vessel provided with two vacuum preliminary chambers (load lock chambers). The wafer is carried in and out through the vacuum preparatory chamber.

  When carrying in / out a wafer, the robot arm first takes out the processed wafer from the vacuum preparatory chamber and transports it to the wafer storage location. Thereafter, an unprocessed wafer is taken out from the wafer storage location, and once placed on the aligner, the posture of the wafer is adjusted (position adjustment based on a notch or an orientation flat). Thereafter, the robot arm carries the wafer from the aligner to the vacuum preparatory chamber.

  Since two vacuum preparatory chambers are provided, the processing speed for carrying in and out the wafer can be increased.

Japanese Patent Publication No. 7-54688

  In the conventional ion implantation apparatus, the time required to carry in / out and carry the wafer is longer than the time during which ion implantation is actually performed on the wafer.

  The objective of this invention is shortening the time of conveyance of a process target object, carrying in / out, and improving the processing capability of a vacuum processing apparatus.

  According to one aspect of the present invention, a vacuum container that defines an internal space that can be evacuated, and a processing object is carried into the vacuum container while maintaining the vacuum state in the vacuum container. A first load lock mechanism that can be carried out of the container; and a first load lock mechanism that is disposed in the vacuum container and holds the processing object; from the processing position where the processing object is processed to the delivery position; and vice versa A holding mechanism that can be moved, and when the holding mechanism holds the processing object at the delivery position, the processing object at the delivery position and the processing object held by the first load lock mechanism; A first arm and a second arm that can pivot independently of each other, wherein the first arm and the second arm The arm is related to the direction of the axis of rotation. The first arm pivots to move the object to be processed from the delivery position to the first load lock mechanism, and at the same time the second arm moves in the reverse direction. And a vacuum processing apparatus for moving another processing object from the first load lock mechanism to the delivery position.

  The processing object at the delivery position and the other processing object held by the first load lock mechanism can be exchanged with each other. This makes it possible to increase the processing capacity.

  FIG. 1 shows a plan view of a vacuum container of an ion implantation apparatus according to an embodiment of the present invention. A first load lock mechanism 1 and a second load lock mechanism 2 are attached to the bottom surface of a vacuum vessel 50 that can be evacuated. The detailed structure of the first and second load lock mechanisms 1 and 2 will be described later with reference to FIG. Via the first load lock mechanism 1 and the second load lock mechanism 2, the wafer is carried into and out of the vacuum container 50.

  Further, the scan arm 9 is disposed in the vacuum container 50. The scan arm 9 holds the wafer on the platen 10 attached to the tip thereof, and places the wafer in the path of the ion beam 30. The traveling direction of the ion beam 30 is substantially horizontal, and the wafer is held perpendicularly or obliquely with respect to the traveling direction of the ion beam 30. A scan motor 20 supports the scan arm 9 and swings it within a certain angle range. As a result, the wafer held on the platen 10 reciprocates so as to cross the path of the ion beam 30. A Faraday cup 31 for measuring ion current is disposed downstream of the ion beam 30.

  A support shaft that supports the scan motor 20 is led out to the outside of the vacuum vessel 50. This spindle is rotated by the tilt motor 21. By operating the tilt motor 21, the platen 10 can be tilted and placed at the load position 10A. In a state where the platen 10 is disposed at the load position 10A, the wafer is held almost horizontally.

  Further, internal arms 7 and 8 are arranged in the vacuum vessel 50. The internal arms 7 and 8 rotate around a rotating shaft 12 disposed at an equal distance from the first load lock mechanism 1 and the second load lock mechanism 2. The distance from the load position 10 </ b> A of the platen 10 to the rotary shaft 12 is equal to the distance from the first load lock mechanism 1 to the rotary shaft 12.

  The inner arms 7 and 8 hold the wafer, and from any position of the first load lock mechanism 1, the second load lock mechanism 2, and the platen 10 arranged at the load position 10A, The wafer can be transferred to the position. The two inner arms 7 and 8 are arranged at different heights from each other, and can be rotated so that they intersect each other. Therefore, for example, the wafer held by the first load lock mechanism 1 and the wafer held by the platen 10 at the load position 10A can be exchanged with each other. Similarly, the wafer held by the second load lock mechanism 2 and the wafer held by the platen 10 at the load position 10A can be exchanged with each other.

  A first robot arm 3, a second robot arm 4, an external arm 5, an aligner 6, a buffer 11, and a hoop 51 are arranged outside the vacuum container 50. The aligner 6 holds the wafer and adjusts the position of the wafer based on the orientation flat and the notch (performs alignment). The buffer 11 temporarily holds the wafer. The aligner 6 and the buffer 11 are arranged at positions that overlap vertically. The hoop 51 stores a plurality of wafers 52. The wafers stored in one FOUP 51 are all unprocessed at the beginning, and the processing proceeds one by one and is replaced with a processed wafer. Eventually, everything is replaced with a processed wafer.

  The first robot arm 3 is an arbitrary one of the two hoops 51 A, the first load lock mechanism 1, the aligner 6, and the buffer 11 that are arranged near the first robot arm 3 among the four hoops 51. Wafers can be transferred from one device to any other device. The external arm 5 can receive the wafer held by the aligner 6 and carry it into the first load lock mechanism 1 or the second load lock mechanism 2. The second robot arm 4 is an arbitrary one of the two hoops 51 </ b> B, the second load lock mechanism 2, the aligner 6, and the buffer 11 that are arranged near the second robot arm 4 among the four hoops 51. Wafers can be transferred from one device to any other device. The first robot arm 3 and the second robot arm 4 can transfer wafers to each other via the buffer 11.

  The first robot arm 3, the second robot arm 4, the external arm 5, the internal arms 7, 8 and the like are controlled by the control device 15.

  FIG. 2 shows a cross-sectional view of the vacuum vessel 50 and the internal structure of the portion to which the first load lock mechanism 1 and the rotary shaft 12 are attached. The structure of the second load lock mechanism 2 is the same as that of the first load lock mechanism 1.

  An opening 55 larger than the wafer is formed on the bottom surface of the vacuum vessel 50. The air cylinder 64 moves the atmosphere side gate valve 61 up and down. When the atmosphere side gate valve 61 rises to the highest position, the opening 55 is closed from the outside of the vacuum vessel 50. FIG. 2 shows a state where the atmosphere side gate valve 61 closes the opening 55. The contact portion between the vacuum vessel 50 and the atmosphere side partition valve 61 is kept airtight by an O-ring.

  The support shaft 62 passes through the center of the atmosphere side gate valve 61. The penetration portion of the support shaft 62 is kept airtight by an O-ring. A wafer elevating table 63 is attached to the tip of a support shaft 62 inside the vacuum vessel 50. An elevating air cylinder 65 is attached to the other end of the support shaft 62. By operating the lift air cylinder 65, the wafer lift table 63 can be lifted and lowered. The processing target wafer 52 is held on the wafer lifting table 63.

  A support shaft 73 penetrating the upper surface of the vacuum vessel 50 is disposed at a position where the support shaft 62 extends upward. The penetrating portion of the support shaft 73 is kept airtight by an O-ring. A vacuum side gate valve 71 is attached to the tip of a support shaft 73 on the inner side of the vacuum vessel 50. An air cylinder 72 that raises and lowers the support shaft 73 and the vacuum side gate valve 71 is attached to the other end of the support shaft 73.

  When the vacuum side gate valve 71 is lowered and brought into contact with the bottom surface of the vacuum vessel 50, the opening 55 is closed by the vacuum side gate valve 71. FIG. 2 shows a state in which the tip of the internal arm 7 is disposed below the vacuum side gate valve 71, but when the vacuum side gate valve 71 is lowered, the internal arm 7 is lowered by the vacuum side gate valve 71. Turn to a position that will not interfere with Further, the wafer lifting table 63 is also lowered to a position that does not prevent the vacuum side gate valve 71 from being lowered. An O-ring is attached to a portion where the vacuum side gate valve 71 and the vacuum vessel 50 are in contact with each other, and airtightness at the contact portion between the two is ensured.

  A double shaft seal unit (rotary shaft) 12 penetrates the upper surface of the vacuum vessel 50. The internal arm 7 is attached to the tip of one of the rotary shafts 12 on the inner side of the vacuum vessel 50, and another internal arm 8 is attached to the tip of the other shaft. One of the double shafts of the rotating shaft 12 is rotationally driven by the motor 81, and the other is rotationally driven by the motor 82.

  In a state where the vacuum side gate valve 71 is raised, the inner arms 7 and 8 can be turned to insert their tips between the wafer lift table 63 and the vacuum side gate valve 71. In this state, the wafer 52 can be transferred between the internal arm 7 or 8 and the wafer lifting table 63.

  When the atmosphere side gate valve 61 is raised to close the opening 55 and the vacuum side gate valve 71 is lowered to close the opening 55, an airtight space is formed between them. Hereinafter, this space is referred to as a load lock chamber. An air supply / exhaust pipe 85 attached to the bottom surface of the vacuum vessel 50 communicates with the load lock chamber. The vacuum pump 86 connected to the supply / exhaust pipe 85 can exhaust the load lock chamber to make a vacuum state. Further, by opening the valve of the nitrogen gas cylinder 87 connected to the supply / exhaust pipe 85, nitrogen gas can be introduced into the load lock chamber to be in an atmospheric pressure state.

  Thus, the load lock chamber can be in a vacuum state and an atmospheric pressure state independently of the space in the vacuum vessel 50. For this reason, the wafer 52 can be carried in and out while maintaining the vacuum in the vacuum container 50.

  A rotating shaft 84 that rotatably supports the external arm 5 is disposed below the vacuum vessel 50. The rotating shaft 84 is disposed on an extension line that extends downward from the rotating shaft 12. The motor 83 rotates the rotating shaft 84.

  With the atmosphere side gate valve 61 and the wafer elevating table 63 lowered, the external arm 5 can be turned and the tip thereof can be placed above the wafer elevating table 63. In this state, the wafer can be transferred from the external arm 5 to the wafer lifting table 63.

  Next, with reference to FIGS. 1 to 3, the steps of wafer transfer and ion implantation will be described. Each of the polygonal lines U1 to U5 shown in FIG. 3 shows a process of transporting one wafer.

  First, the transfer procedure of the wafer U1 will be described. The first robot arm 3 unloads the wafer U1 from the hoop 51. Thereafter, the wafer U 1 is turned to the position of the aligner 6, and the wafer U 1 is loaded on the aligner 6. The aligner 6 detects the position of the notch of the wafer U1 and aligns the wafer U1. When the alignment is completed, the wafer U1 is transferred from the aligner 6 to the external arm 5.

  The external arm 5 turns to the position of the first load lock mechanism 1 to load the wafer U1 on the wafer lift table 63 (see FIG. 2) of the first load lock mechanism 1. The load lock chamber of the first load lock mechanism 1 is evacuated to a vacuum state. After the vacuum state is reached, the vacuum side gate valve 71 and the wafer lifting table 63 are raised.

  The internal arm 7 transfers the wafer U1 to the platen 10 waiting at the load position 10A. When the ion-implanted wafer is held on the platen 10, the other internal arm 8 conveys the processed wafer from the platen 10 to the wafer lifting table 63 of the first load lock mechanism 1. That is, the wafer is exchanged between the first load lock mechanism 1 and the platen 10.

  The platen 10 is moved to the ion implantation position, and ion implantation into the wafer U1 is performed. After the ion implantation, the platen 10 is moved to the load position 10A. By this time, the wafer U2 to be processed next to the wafer U1 has been transferred to the second load lock mechanism 2 via a path to be described later. The wafer U1 held on the platen 10 and the wafer U2 held on the second load lock mechanism 2 are exchanged.

  The wafer U1 is disposed in the load lock chamber of the second load lock mechanism 2. Nitrogen gas is introduced into the load lock chamber, and the wafer U1 is carried out of the vacuum vessel 50. The second robot arm 4 receives the wafer U 1 from the second load lock mechanism 2, turns to the position of the buffer 11, and loads the wafer U 1 into the buffer 11.

  The first robot arm 3 receives the wafer U 1 from the buffer 11, turns to the FOUP 51, and carries the wafer U 1 into the FOUP 51. Through the steps so far, the processing of the wafer U1 is completed.

  In the above process, the first robot arm 3 turns to the position of the first load lock mechanism 1 after carrying the wafer U1 into the aligner 6. The first load lock mechanism 1 holds a wafer on which ion implantation has already been performed. The first robot arm 3 receives the processed wafer from the first load lock mechanism 1, turns to the FOUP 51, and loads the processed wafer into the FOUP 51.

  While the first robot arm 3 is transferring the processed wafer from the first load lock mechanism 1 to the FOUP 51, the external arm 5 transfers the unprocessed wafer U1 to the first load lock mechanism 1. To do. When the external arm 5 is not disposed, these two transfer procedures cannot be performed in parallel. By disposing the external arm 5, it is possible to increase the wafer transfer capability.

  Next, the transfer procedure of the wafer U2 will be described. The first robot arm 3 loads the processed wafer into the FOUP 51, moves to the next slot of the FOUP 51, and unloads the unprocessed wafer U2 from the FOUP 51.

  The unloaded wafer U2 is loaded on the aligner 6 by the first robot arm 3 and aligned. The wafer U <b> 2 whose alignment has been completed is transferred to the second load lock mechanism 2 by the external arm 5. The load lock chamber of the second load lock mechanism 2 is evacuated and carried into the vacuum vessel 50.

  At this time, the ion-implanted wafer U1 is held by the platen 10 and placed at the load position 10A. Exchange of the processed wafer U1 held on the platen 10 and the wafer U2 held on the second load lock mechanism 2 is performed. The wafer U2 is transferred to the ion implantation position, and ion implantation is performed.

  The processed wafer U2 is transferred to the load position 10A. By this time, the wafer U3 to be processed next to the wafer U2 has been carried into the first load lock mechanism 1. The wafer U2 arranged at the load position 10A is exchanged with the wafer U3 held by the first load lock mechanism 1. Thereafter, the wafer U <b> 2 is unloaded from the vacuum vessel 50 via the first load lock mechanism 1, and loaded into the FOUP 51 by the first robot arm 3.

  During the period until the wafer U2 is transferred from the hoop 51 to the external arm 5 via the first robot arm 3 and the aligner 6, the second robot arm 4 has been processed from the second load lock mechanism 2. The wafer is unloaded and loaded into the buffer 11.

  During the period in which the external arm 5 is transporting the wafer U2 to the second load lock mechanism 2, the first robot arm 3 unloads the processed wafer from the buffer 11, pivots to the FOUP 51, and the FOUP 51 Carry in. As described above, since the transfer by the first robot arm 3 and the transfer by the external arm 5 are performed in parallel, the wafer transfer capability can be increased.

  The wafer U3 to be processed next to the wafer U2 passes through the same transfer path as the wafer U1. The wafer U4 to be processed next to the wafer U3 passes through the same transfer path as the wafer U2. In this way, odd-numbered wafers pass through the same transfer path, and even-numbered wafers pass through the same transfer path.

  As described above, by providing the external arm 5 in addition to the first robot arm 3 and the second robot arm 4, the wafer transfer capability can be enhanced.

  In the above embodiment, the ion implantation apparatus has been described as an example. However, the configuration of the apparatus according to the above embodiment can be applied not only to the ion implantation apparatus but also to other vacuum processing apparatuses.

  Although the present invention has been described with reference to the embodiments, the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

It is a plane sectional view of an ion implantation apparatus according to an embodiment. It is sectional drawing of the load lock mechanism part of the ion implantation apparatus by an Example. It is a figure for demonstrating the procedure which conveys a wafer with the ion implantation apparatus by an Example.

Explanation of symbols

1, 2 Load lock mechanism 3, 4 Robot arm 5 External arm 6 Aligner 7, 8 Internal arm 9 Scan arm 10 Platen 11 Buffer 12 Rotating shaft 15 Controller 20 Scan motor 21 Tilt motor 30 Ion beam 31 Faraday cup 50 Vacuum vessel 51 Hoop 52 Wafer 55 Opening 61 Atmosphere side gate valve 62 Support shaft 63 Lifting table 64 Gate valve air cylinder 65 Lift table air cylinder 71 Vacuum side valve 72 Gate valve air cylinder 73 Support shafts 81, 82 Motor 83 for internal arm External arm motor 84 Rotating shaft 85 Air supply / exhaust pipe 86 Vacuum pump 87 Nitrogen gas cylinder

Claims (1)

A vacuum vessel defining an internal space capable of being evacuated;
A first load lock mechanism capable of carrying a processing object into and out of the vacuum container while maintaining the vacuum state in the vacuum container;
A holding mechanism that is disposed in the vacuum vessel, holds a processing object, and can be moved from a processing position where the processing object is processed to a delivery position and vice versa;
An internal arm capable of exchanging the processing object at the delivery position and the processing object held at the first load lock mechanism when the holding mechanism holds the processing object at the delivery position; And the inner arm is
The first arm and the second arm are capable of pivoting independently of each other, and the first arm and the second arm are supported at different positions with respect to the pivoting axial direction. When the first arm is turned, the processing object is moved from the delivery position to the first load lock mechanism, and at the same time, the second arm is turned in the opposite direction, so that another processing object is obtained. A vacuum processing apparatus that moves the first load lock mechanism to the delivery position.

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