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EP0360529B1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Electrostatic chuck

Assignee: Toto Ltd
•
Filing: 1989-09-18
•
Granted: 1997-06-04
•
Expires: 2009-09-18
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Abstract

Abstract An electrostatic chuck for electrostatically attracting and holding an object such as a semiconductor wafer includes a base plate, at least two layers each including an electrically insulating film and an electrode attached to a lower surface thereof, the at least two layers being disposed as attractive layers on the base plate, and a voltage applying assembly for selectively applying a voltage to at least one of the electrodes to electrostatically attract the object to the insulating film of an uppermost one of the layers. The insulating films may have different insulation resistances to allow for a wider range of temperature changes.

Inventors

  • 👤 Toshiya C/O Toto Limited Watanabe
  • 👤 Tetsuo C/O Toto Limited Kitabayashi

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-01 04:03
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/70; H10P72/72; H10P72/722; Y; Y10; Y10T; Y10T279/00; Y10T279/23

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 140 words
An electrostatic chuck for electrostatically attracting and holding an object, comprising: a base plate; at least two layers each including an electrically insulating film and an electrode attached to a lower surface thereof, said at least two layers being disposed as attractive layers on said base plate; one of the said layers comprising alumina with 1.0 wt % titanium oxide having a resistivity range of 10 11 -10 12 ohm cm. in the temperature range 300-473 K and the second of the said layers comprising alumina with 0.3 wt % titanium oxide having a resistivity of 10 11 -10 12 ohm cm. in the temperature range 473-673 K and voltage applying means for selectively applying a voltage to at least one of said electrodes to electrostatically attract an object to the insulating film of the uppermost one of said layers.
Claim 2
Dependent Claim 31 words
An electrostatic chuck according to claim 1, wherein each of said electrodes comprises a single electrode film covering substantially the entire lower surface of each one of said electrically insulating films.
Claim 3
Dependent Claim 36 words
An electrostatic chuck according to claim 1, wherein each of said electrodes comprises a plurality of electrode films of a desired shape covering substantially the entire lower surface of each one of said electrically insulating films.
Claim 4
Dependent Claim 49 words
An electrostatic chuck according to claim 1, wherein said voltage applying means comprises means for applying a DC voltage to one of said electrodes and applying an AC voltage to the other of said electrodes when an object which is electrostatically attracted and held is processed by plasma etching.
Claim 5
Dependent Claim 22 words
An electrostatic chuck according to claim 1, wherein the upper insulating film is of a lower resistance than the lower insulating film.

References Cited (Backward Citations)

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