Electrostatic Force and Absorption Current of Alumina Electrostatic Chuck

Electrostatic chucks composed of alumina ceramics doped with 1.3 wt% TiO₂ and 3.5 wt% Cr₂O₃ were fabricated. Evaluations of electrostatic force and absorption charge in various atmospheres were carried out. The electrostatic force in various atmospheres clarified that the electrostatic force is affected not only by the bulk resistance, but also by the surface resistance of the ceramics. Absorption charge measurements revealed that the surface resistance affects the charge distribution of the dielectric layer, and it is deduced that the large electrostatic force of the alumina electrostatic chuck in the vacuum atmosphere is explained by the space charge which concentrates on the dielectric layer and intensity contact potential difference.