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EP0357424A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

A wafer supporting apparatus

Assignee: Canon Inc
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Filing: 1989-08-31
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Granted: —
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Expires: 2009-08-31
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Abstract

Abstract A wafer chuck (2) usable with a semiconductor exposure apparatus (Fig.2A) wherein a mask and a semiconductor wafer (1) are placed in a vacuum ambience or a pressure-reduced gas ambience, and wherein the wafer (1) is exposed through the mask to radiation energy such as X-rays contained in a synchrotron radiation beam, by which the pattern of the mask is transferred onto the wafer (1). The wafer (1) is first attracted on the wafer supporting surface of the chuck (2) by vacuum attraction (21), and thereafter, the wafer (1) is attracted by electrostatic attraction force. Thereafter, the vacuum attraction is broken by supplying (24) a gas. Preferably Helium or other thermally conductive gas is admitted at this point. When the pattern of the mask is transferred onto the wafer (1), the wafer (1) is retained on the wafer supporting surface (20) by the electrostatic attraction force only. By this, the wafer supporting apparatus can correctly contact the wafer supporting surface (20) to the wafer (1) without being influenced by the undulation of the wafer (1). In addition, the heat produced in the wafer (1) during exposure can be removed efficiently by temperature controlled (23) water (11) supplied to the wafer supporting apparatus (2).

Inventors

  • 👤 Eiji Sakamoto
  • 👤 Shinichi Hara
  • 👤 Isamu Shimoda
  • 👤 Shunichi Uzawa

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-01 08:53
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70691; G03F7/707; G03F7/708; G03F7/70858; G03F7/70866; G03F7/70875; H; H10; H10P; H10P72/00; H10P72/70; H10P72/72; H10P72/722; H10P72/78

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 58 words
An apparatus for supporting a member, comprising: a surface for supporting the member; vacuum attraction means for attracting the member onto said attracting surface by vacuum attraction force; electrostatic attraction means for attracting the member onto said supporting surface by electrostatic force; and control means for operating said electrostatic attraction means after said vacuum attraction means is operated.
Claim 2
Independent Claim 58 words
An apparatus for supporting a member, comprising: a surface for supporting the member; vacuum attraction means for attracting the member onto said attracting surface by vacuum attraction force; electrostatic attraction means for attracting the member onto said supporting surface by electrostatic force; and control means for operating said electrostatic attraction means after said vacuum attraction means is operated.
Claim 3
Dependent Claim 40 words
An apparatus according to Claim 1, wherein said vacuum attraction means is provided with grooves formed on said supporting surface, a vacuum source for applying vacuum to said grooves and a gas inlet for supplying a gas into said grooves.
Claim 4
Dependent Claim 26 words
An apparatus according to Claim 2, wherein said control means introduces gas through the gas inlet to said grooves after said electrostatic attraction means is operated.
Claim 5
Dependent Claim 35 words
An apparatus according to Claim 2, wherein said control means stops operation of said vacuum attraction means and introduces through said gas inlet the gas into said grooves after it operates said electrostatic attraction means.
Claim 6
Dependent Claim 45 words
An apparatus according to Claim 1, wherein said control means includes a pressure sensor, and wherein said control means operates said electrostatic attraction means after it detects by the pressure sensor secure retention of the member on said supporting surface by said vacuum attraction means.
Claim 7
Dependent Claim 74 words
A supporting apparatus for supporting a member, comprising: a main assemly having a supporting surface for supporting the member; temperature control means for circulating a temperature-controlled medium in said main assembly; vacuum attraction means for attracting the member on said supporting surface by vacuum attraction force; electrostatic attraction means for attracting the member onto said supporting surface by electrostatic force; control means for operating said electrostatic attraction means after operating said vacuum attraction means.
Claim 8
Dependent Claim 74 words
A supporting apparatus for supporting a member, comprising: a main assemly having a supporting surface for supporting the member; temperature control means for circulating a temperature-controlled medium in said main assembly; vacuum attraction means for attracting the member on said supporting surface by vacuum attraction force; electrostatic attraction means for attracting the member onto said supporting surface by electrostatic force; control means for operating said electrostatic attraction means after operating said vacuum attraction means.
Claim 9
Dependent Claim 16 words
An apparatus according to Claim 6, wherein said control means also controls said temperature control means.
Claim 10
Dependent Claim 105 words
An exposure apparatus wherein exposure energy is applied onto a wafer through a mask, by which a pattern formed in the mask is transferred onto the wafer, comprising: a main assembly having a wafer supporting surface; vacuum attraction means for attracting the wafer onto said wafer supporting surface by vacuum attraction force; electrostatic attraction means for attracting the wafer onto said wafer supporting surface by electrostatic attraction force; control means for operating said electrostatic attraction means after operating said vacuum attraction means, wherein said control means retains the wafer on said wafer supporting surface only by electrostatic attraction means during application of the exposure energy.
Claim 11
Dependent Claim 105 words
An exposure apparatus wherein exposure energy is applied onto a wafer through a mask, by which a pattern formed in the mask is transferred onto the wafer, comprising: a main assembly having a wafer supporting surface; vacuum attraction means for attracting the wafer onto said wafer supporting surface by vacuum attraction force; electrostatic attraction means for attracting the wafer onto said wafer supporting surface by electrostatic attraction force; control means for operating said electrostatic attraction means after operating said vacuum attraction means, wherein said control means retains the wafer on said wafer supporting surface only by electrostatic attraction means during application of the exposure energy.

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