Alumina electrostatic chucks for silicon wafer process with wide range of electrical resistivity were fabricated by controlling the amount of TiO₂ addition(0, 1.3, 2.0, 2.8 wt%). The dependence of electrostatic force on applied voltage, temperature and humidity was investigated. In addition, response characteristics on applied voltage and relationship between electrical resistivity and electrostatic force characteristics such as Coulomb force and Johnsen-Rahbeck force were discussed.