ELECTROSTATIC CHARGE-DISTRIBUTION IN THE DIELECTRIC LAYER OF ALUMINA ELECTROSTATIC CHUCK

Electrostatic charge and its distribution in the dielectric layer of T iO2- and Cr2O3-added alumina electrostatic chucks has been studied. Th e electrostatic potential was evaluated,at various applied voltages by an electrostatic potential meter and it demonstrated the existence of charges with opposite polarities. Direct SEM observation and toner de velopment of the charged ceramic surface was carried out to clarify th e charge distribution. The charge contrast was not uniform on the cera mic microstructure and the charge was distributed in the form of grain s. Taking into consideration these results, the relationship between e lectrostatic charge distribution and ceramic microstructure is discuss ed.