Electrostatic chuck
AssigneeNHK Spring Co., Ltd.
InventorsShinji Saito, Toshihiko Hanamachi, Takashi Kayamoto
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Abstract
An electrostatic chuck comprising a ceramic chuck body having an adsorption face and an electrode for applying a potential to the adsorption face, the chuck body including a ceramic consisting mainly of MgO. The ceramic that consists mainly of MgO is doped with one or more additives selected from a group including TiC, TiO2, ZrO2, V2O5, Nb2O5, Ta2O5, Co3O4, Cr2O3, and NiO so that its electrical resistivity in a working temperature region ranges from 1×108 to 1×1012 Ω·cm. This electrostatic chuck is highly resistant to a corrosive environment such as fluoride plasma.
Claims2
An electrostatic chuck comprising:
- a chuck body having an adsorption face which electrostatically adsorbs a to-be-adsorbed object;
- and
- an electrode for applying a potential to the adsorption face;
- wherein the chuck body includes a ceramic containing at least 85% MgO, doped with TiC and one or two oxides selected from the group consisting of Co3O4, Cr2O3 and NiO serving to form a solid solution, the ceramic having an electrical conductivity in a working temperature region, and wherein an adsorption force based on Johnsen-Rahbek effect is produced by charged polarization on the adsorption face when the potential is applied to the electrode.
Dependencies are inferred from the claim text.