Patent ID: 6422173
Filing Date: 2002-07-23
Classification: H01J

Abstract:
An inductively coupled plasma etching apparatus, comprising:a chamber; a window for sealing a top opening of the chamber, the window having an inner surface that is exposed to an internal region of the chamber; a metal plate disposed above and spaced apart from the window; a coil disposed above the metal plate, the coil being spaced part from the metal plate, and the coil being conductively connected to the metal plate at a connection location that is configured to generate a peak-to-peak voltage on the metal plate that optimally reduces sputtering of the inner surface of the window while substantially simultaneously preventing deposition of etch byproducts on the inner surface of the window; and an oscillation circuit coupled to the metal plate, the oscillation circuit being controllable to further adjust the peak-to-peak voltage on the metal plate.