Wafer transfer system

• US 6,224,680 B1
• Filed: 03/09/1999
• Issued: 05/01/2001
• Est. Priority Date: 07/09/1996
• Status: Expired due to Term

• Current Assignee: Novellus Systems Incorporated (LAM Research Corporation)
• Original Assignee: Gamma Precision Technology, Inc. (LAM Research Corporation)
• Inventors: Toshima, Masato
• Primary Examiner(s): Mills, Gregory
• Assistant Examiner(s): ALEJANDRO MULERO, LUZ L
• Application Number:
  US09/265,490
• Time in Patent Office: 784 Days
• Field of Search: 118/719, 118/723 R, 118/728, 118/729, 118/730, 118/500, 156/345, 204/298.25, 204/298.35, 414/217, 414/219, 414/220, 414/930, 414/936, 414/937, 414/938, 414/939, 414/940
• US Class Current: 118/719
• CPC Class Codes: C23C 16/54 Apparatus specially adapted for continuous coating
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 21/67745 characterized by movements or sequence of movements of transfer devices
• CPC Class Codes: H01L 21/67748 horizontal transfer of a single workpiece
• CPC Class Codes: H01L 21/67757 vertical transfer of a batch of workpieces
• CPC Class Codes: H01L 21/67778 involving loading and unloading of wafers
• CPC Class Codes: H01L 21/6838 with gripping and holding devices using a vacuum; Bernoulli devices

Abstract

A wafer transfer system is described for transferring a wafer while at substantially the same time another wafer is being processed. The wafer transfer system comprises, in one embodiment, a transfer chamber having a wafer transfer blade, a load lock chamber coupled to the transfer chamber, a robot for loading and unloading the wafer into the load lock chamber, and a slider coupled to the wafer transfer blade for moving the wafer transfer blade between the transfer chamber and the load lock chamber. According to a preferred embodiment, the slider utilizes a magnetic coupling mechanism.

Claims

1. A device for processing a plurality of wafers, comprising:

a transfer chamber within which processing of said plurality of wafers takes place;

a load lock chamber coupled to said transfer chamber;

a plurality of stages located within and coupled to said transfer chamber, said stages being disposed at a predetermined radius from a hub concentrically located within and operatively coupled to said transfer chamber, each of said plurality of stages being capable of supporting one of said plurality of wafers during processing;

a transfer blade located within and operationally coupled to said transfer chamber, said transfer blade having a retracted and an extended position;

in said retracted position, said transfer blade is located at said predetermined radius, in said extended position said transfer blade is in said load lock chamber, said transfer blade being capable of transferring said plurality of wafers one at a time from said load lock chamber to said transfer chamber or from said transfer chamber to said load lock chamber while others of said plurality of wafers are being processed on said plurality of stages within said transfer chamber; and

,

a plurality of fins having a first end and a second end, said first end of each of said fins being coupled to said hub, said second end of each of said fins being located at said predetermined radius, said fins being capable of synchronous movement about said hub, said fins further being in communication with said plurality of stages and said transfer blade such that each of said plurality of fins can transfer one of said plurality of wafers from said transfer blade to one of said plurality of stages, from one of said plurality stages to another of said plurality of stages or from one of said plurality of stages to said transfer blade.

2. The device of claim 1, wherein said transfer blade comprises,

a first magnet coupled to said transfer blade wherein said first magnet is located adjacent to the interior surface of a wall of said transfer chamber; and,

a second magnet located adjacent to an exterior surface of said wall of said transfer chamber opposite to said interior surface of said wall of said transfer chamber wherein said second magnet is operatively coupled to said first magnet such that movement of said second magnet results in a corresponding movement of said first magnet and said transfer blade.

3. The device of claim 1, comprising a robot wherein said robot is:

operatively coupled to said load lock chamber; and

,

located external to said load lock chamber.

4. The device of claim 3, wherein said robot comprises a plurality of platens, each of said plurality of platens being capable of supporting one of a plurality of wafers.

5. The device of claim 4, wherein each of said plurality of platens comprises a vacuum chuck.

6. The device of claim 5, comprising a plurality of cassette holders wherein each of said plurality of cassette holders is:

independently capable of holding said plurality of wafers; and

,

operatively coupled to said robot such that said robot is capable of independently delivering to and receiving from each of said plurality of cassette holders all of said plurality of wafers in said cassette holder.

7. The device of claim 6, wherein said plurality of cassette holders comprises two cassette holders, each said cassette holder being capable of holding 25 wafers.

8. The device of claim 1, comprising a plurality of plasma sources coupled to said transfer chamber wherein each of said plurality of plasma sources is independently capable of generating a plasma.

9. The device of claim 8, wherein each of said plurality of plasma sources is located above one of said plurality of stages.

10. The device of claim 1, wherein the temperature of each of said plurality of stages is capable of being independently controlled.

11. The device of claim 1, wherein said load lock chamber comprises a wafer holder having a plurality of shelves capable of holding said plurality of wafers.

12. The device of claim 11, wherein said wafer holder is capable of holding fifty wafers.

13. The device of claim 11, wherein said wafer holder comprises a counterbalancing means for supporting said wafer holder in the event of a power failure.

14. The device of claim 13, wherein said wafer holder is operatively coupled to a plurality of vertical bars which, when cause to move by a pneumatic actuator, center said wafers in said wafer holder.

15. The device of claim 1, wherein said load lock chamber comprises a gate valve coupled to said load lock chamber such that when said gate valve is open said load lock chamber is open to an atmosphere external to said device and when said gate valve is closed said load lock chamber is isolated from said external atmosphere.

16. The device of claim 1, comprising a slit valve coupled to said load lock chamber and to said transfer chamber such that, when said slit valve is open, said load lock chamber is open to said transfer chamber and, when said slit valve is closed, said load lock chamber is isolated from said transfer chamber.

17. The device of claim 1, wherein said plurality of wafers comprises fifty wafers.

18. The device of claim 1, wherein said plurality of stages comprises six stages.

19. The device of claim 18, wherein said plurality of fins comprises seven fins.