Hybrid thermal electrostatic clamp

摘要

An electrostatic clamp having improved temperature uniformity is disclosed. The electrostatic clamp includes an LED array mounted along an annular ring so as to illuminate the outer edge of the workpiece. The LEDs in the LED array may emit light at a wavelength readily absorbed by the workpiece, such as between 0.4 μm and 1.0 μm. The center portion of the workpiece is heated using conductive heating provided by the heated electrostatic clamp. The outer portion of the workpiece is heated by light energy from the LED array. The LED array may be disposed on the base of the electrostatic clamp, or may be disposed on a separate ring. The diameter of the upper dielectric layer of the electrostatic clamp may be modified to accommodate the LED array.

主权项

1. An electrostatic clamp, comprising:
a base having a top surface with a first diameter; an upper dielectric layer having a bottom surface with a second diameter, wherein the bottom surface of the upper dielectric layer is disposed on the top surface of the base and the second diameter is less than the first diameter, so as to create a horizontal annular ring on the top surface of the base; and a LED array disposed on the horizontal annular ring.