Substrate holder and substrate holding method

• US 20100267317A1
• Filed: 12/23/2009
• Published: 10/21/2010
• Est. Priority Date: 12/25/2008
• Status: Active Grant

• Current Assignee: Ebara Corporation
• Original Assignee: Ebara Corporation
• Inventors: Takahashi, Tamami, Seki, Masaya, Kusa, Hiroaki
• Granted Patent: US 8,506,363 B2
• Time in Patent Office: Days
• US Class Current: 451/388
• CPC Class Codes: B23Q 3/088 using vacuum means
• CPC Class Codes: B24B 37/30 for single side lapping of plane surfaces
• CPC Class Codes: B24B 41/068 Table-like supports for panels, sheets or the like
• CPC Class Codes: H01L 21/6838 with gripping and holding devices using a vacuum; Bernoulli devices
• CPC Class Codes: H01L 21/6875 characterised by a plurality of individual support members, e.g. support posts or protrusions
• CPC Class Codes: H01L 21/68792 characterised by the construction of the shaft

Abstract

A substrate holder is a mechanism for holding a substrate, to be polished, by vacuum suction. The substrate holder includes a substrate-holding stage having a suction surface for the substrate, and a fluid passage selectively coupled to a vacuum source and a fluid supply source. The suction surface has a plurality of closed sections surrounded by convexities, and the fluid passage includes a plurality of communication passages which are in fluid communication with the plurality of closed segments respectively and independently.

Claims

1. A substrate holder for holding a substrate by vacuum suction, said substrate holder comprising:

a substrate-holding stage having a suction surface for the substrate; and

a fluid passage selectively coupled to a vacuum source and a fluid supply source,

wherein said suction surface has a plurality of closed sections surrounded by convexities, and

wherein said fluid passage includes a plurality of communication passages which are in fluid communication with said plurality of closed segments respectively and independently.

2. The substrate holder according to claim 1, wherein said substrate-holding stage includes a plurality of support members having a height equal to that of said convexities, and said plurality of support members are arranged in said plurality of closed sections.

3. The substrate holder according to claim 1, wherein:

said plurality of communication passages branch off from a single main passage; and

flow-rate regulators for regulating a flow rate of fluid are provided in said plurality of communication passages.

4. The substrate holder according to claim 3, wherein said flow-rate regulators are orifices that provide resistance to flow of the fluid.

5. The substrate holder according to claim 1, wherein:

said substrate-holding stage has a suction pad that is brought into contact with the substrate; and

said convexities are formed by said suction pad.

6. The substrate holder according to claim 1, wherein:

said substrate-holding stage has a sheet suction pad that is brought into contact with the substrate; and

said convexities and said closed sections are formed on a surface of said suction pad.

7. The substrate holder according to claim 1, wherein said convexities are O-rings.

8. The substrate holder according to claim 1, wherein said suction surface is smaller than the substrate.

9. A method of holding a substrate, said method comprising:

holding the substrate via vacuum suction by a substrate holder;

performing a first process on the substrate while holding the substrate;

after said first process, lowering a degree of vacuum of the vacuum suction;

performing a second process on the substrate while holding the substrate with the lowered degree of vacuum; and

after said second process, releasing the substrate from the substrate holder by blowing a fluid to the substrate.

10. The method of holding the substrate according to claim 9, wherein an external force acting on the substrate during said second process is smaller than an external force acting on the substrate during said first process.

11. The method of holding the substrate according to claim 9, wherein the fluid is one of air, nitrogen gas, and water.