Hybrid thermal electrostatic clamp
US9633886B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 2015 |
| Grant date | Apr 25, 2017 |
| Priority date | — |
| Expiry date | Aug 24, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/68735
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.