EP0074691A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electrostatic chuck for holding a semiconductor wafer
Assignee: Koninklijke Philips NV
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Filing: 1982-09-09
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Granted: —
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Expires: 2002-09-09
Abstract
Abstract An electrostatic chuck for holding a semiconductor wafer (1) flat in a charged particle beam machine has thermally conductive portions (7) for supporting the wafer. An electrically conductive member (10), for example a grid, has parts which extend between portions (7) and is separated from wafer (1) by a dielectric layer (12). The wafer (1) is clamped against the chuck by the electrostatic force set up across layer (12) when a potential difference is applied between wafer (1) and member (10). Thus heat generated in the wafer by the bombardment of charged particles can be dissipated readily via the thermally conductive portions (7). The wafer (1) can be electrically contacted at it's back surface if the portions (7) are also electrically conductive. To enhance thermal conduction away from the wafer, portions (7) can be proud of the dielectric layer (10).
Inventors
- 👤 Ian Hale Lewin
- 👤 Michael John Plummer
- 👤 Rodney Ward
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 02:18
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/50; H10P72/70; H10P72/72; H10P72/722; Y; Y10; Y10S; Y10S269/00; Y10S269/903; Y10T; Y10T279/00; Y10T279/23
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
89 words
An electrostatic chuck for holding a semiconductor wafer in a fixed plane relative to said chuck, which chuck comprises an electrically conductive member separated from said fixed plane by a layer of dielectric material, means for electrically contacting the wafer, and means for supporting the wafer in said plane, characterized in that the chuck further comprises thermally conductive portions for contacting the wafer, and in that the electrically conductive member has parts which extend laterally between said thermally conductive portions, the dielectric layer extending at least on said parts.
Claim 2
Dependent Claim
89 words
An electrostatic chuck for holding a semiconductor wafer in a fixed plane relative to said chuck, which chuck comprises an electrically conductive member separated from said fixed plane by a layer of dielectric material, means for electrically contacting the wafer, and means for supporting the wafer in said plane, characterized in that the chuck further comprises thermally conductive portions for contacting the wafer, and in that the electrically conductive member has parts which extend laterally between said thermally conductive portions, the dielectric layer extending at least on said parts.
Claim 3
Dependent Claim
22 words
An electrostatic chuck as claimed in Claim 1, characterized in that the thermally conductive portions constitute the means for supporting the wafer.
Claim 4
Dependent Claim
33 words
3: An electrostatic chuck as claimed in Claim 1 or Claim 2, characterized in that the chuck comprises a thermally conductive support having a periphery in thermal contact with the thermally conductive portions.
Claim 5
Dependent Claim
24 words
An electrostatic chuck as claimed in Claim 3, characterized in that the thermally conductive periphery has a major surface coincident with the fixed plane.
Claim 6
Dependent Claim
42 words
An electrostatic chuck as claimed in any of the preceding Claims, characterized in that the thermally conductive portions are electrically conductive and constitute the electrical contact means for the wafer, said thermally conductive members being electrically isolated from the electrically conductive member.
Claim 7
Dependent Claim
29 words
An electrostatic chuck as claimed in Claim 5, characterized in that the thermally conductive portions are electrically isolated from the electrically conductive member by the layer of dielectric material.
Claim 8
Dependent Claim
19 words
An electrostatic chuck as claimed in any of the preceding Claims, characterized in that the dielectric material is transparent.
Claim 9
Dependent Claim
35 words
An electrostatic chuck as claimed in any of the preceding Claims, characterized in that the thermally conductive portions are proud of the dielectric layer so that the dielectric is spaced apart from said fixed plane.
Claim 10
Dependent Claim
30 words
An electrostatic chuck as claimed in any of the preceding Claims, characterized in that the thermally conductive portions are pillars having flat end faces which lia in the fixed plane.
Claim 11
Dependent Claim
28 words
An electrostatic chuck as claimed in Claim 9, characterized in that the electrically conductive member is a grid, the conductive pillars extending through the meshes of said grid.
Claim 12
Dependent Claim
42 words
An electrostatic chuck as claimed in either of Claims 9 or 10 when appendant from Claim 3, characterized in that the support has a perforated central portion which is thinner than the periphery, the thermally conductive pillars being secured in the perforations.
Claim 13
Dependent Claim
40 words
An electrostatic chuck as claimed in any of Claims 1 to 8, characterized in that the thermally conductive portions are constituted by a thermally conductive grid, the electrically conductive member having parts which extend between the meshes of said grid.
Claim 14
Dependent Claim
32 words
An electrostatic chuck as claimed in Claim 12, characterized in that the electrically conductive member comprises a plate which is integral with said parts which extend between the meshes of the grid.
Claim 15
Dependent Claim
39 words
An electrostatic chuck as claimed in either Claims 12 or 13 when appendant from Claim 3, characterized in that the thermally conductive grid forms the central part of the support and is integral with the periphery of said support.
References Cited (Backward Citations)
No citation records indexed.
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