Patent ID: 9716028
Date: 2017-07-25
CPC Classifications: B23Q,H01L,Y10T

Claim:
1. A method of manufacturing a clamping apparatus for maintaining a workpiece flatness during processing, comprising: mounting two sets of clamping mechanisms on a base and each clamping mechanism including a clamp head at a distal end of a rod extending from a housing configured to be in overlapping relation to a first workpiece, each set of the clamp heads extending below the rod, and being in spaced relationship to each other defining a second workpiece area for a second workpiece, and the clamp heads being configured to mate with a top surface of the first workpiece; and coupling a biasing member including a spring washer to each of the housings, the biasing members communicating with the rods via the housings and applying a downward vertical force to the housings and rods and therethrough the clamp heads for applying a downward vertical pressure transmitted only by the clamp heads to the first workpiece such that the first workpiece is discouraged to thermally expand in a vertical direction with respect to a horizontal plane; and wherein the mounting two sets of clamping mechanisms on the base comprises: positioning a shaft integral to each housing through the base from a top side of the base.