Dry etching apparatus

Abstract

Abstract PURPOSE:To reduce the etching rate in the peripheral region close to the orientation flat for ensuring good uniformity in the etching, by forming a section on a supporting electrode of a material serving to reduce the etchant. CONSTITUTION:A wafer 104 covered with an aluminium film is transferred to a predetermined position on a table 112 in a reaction chamber 101, which is then evacuated through an exhaust tube 109. After that, a reaction gas is introduced into the chamber through gas injection openings 108 from a gas inlet tube 110. High frequency power is applied between a supporting electrode 102 and an opposing electrode 103 by a high frequency power source 107, so that etchant is produced by electric discharge, and the aluminium on the surface of the wafer 104 can be etched thereby. The surface of the supporting electrode near the orientation flat is made of a material absorbing or comsuming the etchant, so that the density of the etchant is reduced in that region, and therefore the rate of etching is reduced in the peripheral region close to the orientation flat. Accordingly, the uniformity of etching in a wafer can be improved.

Inventors

• 👤 Etsuo Wani
• 👤 和仁　悦夫

Bibliographic Details