US Patent 10249526 Substrate support assembly for high temperature processes

An electrostatic chuck comprises a ceramic body having a top and a bottom, one or more heating elements disposed in the ceramic body, and one or more electrodes disposed in the ceramic body. The electrostatic chuck further comprises a plurality of objects bonded to the bottom of the ceramic body by a metal bond, wherein collectively the plurality of objects comprise a plurality of features distributed over the bottom of the ceramic body at a plurality of different distances from a center of a circle defined by the bottom of the ceramic body, and wherein a feature of the plurality of features accommodates a fastener.