surface treatment equipment

Abstract

Abstract PURPOSE:To uniformly treat the surface of a material with high accuracy, by providing monitors for monitoring the progress state of surface treatment in several sections of the surface independently from each other, and by controlling the amounts of ion beams applied to these sections based on the output data from these monitors. CONSTITUTION:A wafer 7 is rotated so that variations in etching grade are produced concentrically. The surface of the wafer 7 is then separated into annular sections and the progress of etching in each section is monitored by means of the spectral analysis. This monitoring is performed by passing light beams from the monitored section through spectral filters 15, optical fibers 16, phototransistors 17, low-pass filters 11 and differentiating circuits 12 and they are compared with each other in a voltage comparing circuit 13. The result is fed back to power sources 14 and potentials controlled according to the feed back are applied respectively to the annularly separated electrode pieces 5 of an electrode for drawing out ions.

Inventors

• 👤 Toshiaki Yoshikawa
• 👤 俊明 吉川

Bibliographic Details