Polishing apparatus for finishing semiconductor wafer at high polishing rate under economical running cost

• US 5,749,771 A
• Filed: 02/22/1995
• Issued: 05/12/1998
• Est. Priority Date: 02/22/1994
• Status: Expired due to Fees

• Current Assignee: NEC Electronics Corporation (Renesas Electronics Corporation)
• Original Assignee: NEC Corporation
• Inventors: Isobe, Akira
• Primary Examiner(s): MORGAN, EILEEN P
• Application Number:
  US08/394,169
• Time in Patent Office: 1,175 Days
• Field of Search: 451/41, 451/57, 451/56, 451/283, 451/285, 451/286, 451/287, 451/443, 451/444, 451/36, 451/397, 451/398, 451/402
• US Class Current: 451/41
• CPC Class Codes: B24B 37/32 Retaining rings
• CPC Class Codes: B24B 53/017 Devices or means for dressing, cleaning or otherwise conditioning lapping tools

Abstract

A polishing apparatus is equipped with a wafer holder and a pad conditioner concurrently changed to working position over a polishing pad, and the polishing pad grinds the semiconductor wafer under concurrent cleaning operation thereon so as to enhance the throughput of the polishing apparatus: grooves are formed in a wafer carrier of the wafer holder for sufficiently supplying polishing slurry to the semiconductor wafer, and a guide wall is provided over the polishing pad so as to cause the polishing slurry to partly return to a central area of the polishing pad.

Claims

1. A polishing apparatus for grinding a semiconductor wafer, comprising:

a table driven for rotation;

a polishing pad provided on a surface of said table that rotates together with said table;

a slurry supplying system provided over said polishing pad for supplying a polishing slurry thereto;

a wafer holder system retaining at least one semiconductor wafer for pressing a surface of said at least one semiconductor wafer against said polishing pad; and

a pad conditioning system operative to clean said polishing pad while said semiconductor wafer is being polished on said polishing pad;

wherein said wafer holder system and said pad conditioning system are combined into a combined system which comprises;

a movable arm member;

a carrier block connected to said arm member and moved into and out of a space over said polishing pad;

a retainer retaining said at least one semiconductor wafer in cooperation with said carrier block and allowing said at least one semiconductor wafer to project therefrom; and

a cleaner attached to said retainer;

said carrier block concurrently pressing said at least one semiconductor wafer and said cleaner against said polishing pad.

2. The polishing apparatus as set forth in claim 1, further comprising a controlling unit associated with said wafer holder system and said pad conditioning system and operative to concurrently change said wafer holder system and said pad conditioning system into respective working positions where said at least one semiconductor wafer is pressed against said polishing pad which is being subjected to the cleaning.

3. The polishing apparatus as set forth in claim 2, in which said wafer holder system rotates said at least one semiconductor wafer on said polishing pad.

4. The polishing apparatus as set forth in claim 1, in which said carrier block is driven for rotation so that said at least one semiconductor wafer and said cleaner turn on said polishing pad.

5. A polishing apparatus for grinding a semiconductor wafer, comprising:

a table driven for rotation;

a polishing pad provided on a surface of said table and rotating together with said table;

a slurry supplying system provided over said polishing pad for supplying a polishing slurry thereto; and

a wafer holder system pressing a surface of at least one semiconductor wafer against said polishing pad, said wafer holder system having a carrier block and a retainer ring attached to said carrier block for retaining said at least one semiconductor wafer therebetween, said surface of said at least one semiconductor wafer projecting from an opening of said retainer ring so that said surface of said at least one semiconductor wafer can contact said polishing pad;

wherein at least one groove is formed in said retainer ring so as to supply said polishing slurry through said groove to said surface of said at least one semiconductor wafer;

wherein a cleaner is attached to the retainer ring so as to clean said polishing pad in a polishing work on said at least one semiconductor wafer.

6. The polishing apparatus as set forth in claim 5 further comprising a pad conditioning system operative to clean said polishing pad while said semiconductor wafer is being polished on said polishing pad.

7. The polishing apparatus as set forth in claim 5, in which said carrier block is driven for rotation so as to rotate said at least one semiconductor wafer and said cleaner on said polishing pad.

8. The polishing apparatus as set forth in claim 5, in which said groove radially extends in said retainer.

9. The polishing apparatus as set forth in claim 5, in which said groove extend in a tangential direction of said retainer ring, and said carrier block is driven for rotation so as to rotate said at least one semiconductor wafer and said retainer ring on said polishing pad.

10. A polishing apparatus for grinding a semiconductor wafer, comprising:

a table driven for rotation;

a polishing pad provided on a surface of said table and rotating together with said table;

a slurry supplying system provided over said polishing pad for supplying a polishing slurry thereto;

a wafer holder system retaining at least one semiconductor wafer for pressing a surface of said at least one semiconductor wafer against said polishing pad; and

a guide member stationary with respect to said table and held in contact with said polishing pad for forcing a part of said polishing slurry to return from an outer periphery of said polishing pad to a center area of said polishing pad.

11. The polishing apparatus as set forth in claim 10, further comprising a pad conditioning system operative to clean said polishing pad while said semiconductor wafer is being polished on said polishing pad.

12. The polishing apparatus as set forth in claim 10, in which said wafer holder system comprises a carrier block and a retainer ring attached to said carrier block for retaining said at least one semiconductor wafer therebetween, said surface of said at least one semiconductor wafer projecting from an opening of said retainer ring so that said surface of said at least one semiconductor wafer can contact said polishing pad;

wherein at least one groove is formed in said retainer ring so as to supply said polishing slurry through said groove to said surface of said at least one semiconductor wafer.

15. The polishing apparatus as set forth in claim 12, in which said groove radially extends in said retainer.

16. The polishing apparatus as set forth in claim 12, in which said groove extend in a tangential direction of said retainer ring, and said carrier block is driven for rotation so as to rotate said at least one semiconductor wafer and said cleaner on said polishing pad.

17. The polishing apparatus as set forth in claim 10, in which said guide member includes a portion which is held in contact with said polishing pad.

18. The polishing apparatus as set forth in claim 17, in which said portion is formed of a substance selected from the group consisting of diamond, metal and ceramics.

13. A polishing apparatus for grinding a semiconductor wafer, comprising:

a table driven for rotation;

a polishing pad provided on a surface of said table and rotating together with said table;

a slurry supplying system provided over said polishing pad for supplying a polishing slurry thereto;

a wafer holder system retaining at least one semiconductor wafer for pressing a surface of said at least one semiconductor wafer against said polishing pad; and

a guide member stationary with respect to said table and held in contact with said polishing pad for forcing a part of said polishing slurry to return from an outer periphery of said polishing pad to a center area of said polishing pad;

wherein said wafer holder system comprises a carrier block and a retainer rind attached to said carrier block for retaining said at least one semiconductor wafer therebetween, said surface of said at least one semiconductor wafer projecting from an opening of said retainer ring so that said surface of said at least one semiconductor wafer can contact said polishing pad;

wherein at least one groove is formed in said retainer ring so as to supply said polishing slurry through said groove to said surface of said at least one semiconductor wafer; and

wherein a cleaner is attached to the retainer ring so as to clean said polishing pad in a polishing work on said at least one semiconductor wafer.

14. The polishing apparatus as set forth in claim 13, in which said carrier block is driven for rotation so as to rotate said at least one semiconductor wafer and said cleaner on said polishing pad.