SnO₂膜のテーパエッチ

抄録

A new taper etching technique for SnO₂ transparent conductive films has been successfully developed. The AZ-1350J photoresist patterns with a convex-lens-like cross-section are employed asthe mask for rf sputter etching of the SnO₂ films. The primary rectangular cross-section of the photoresist pattern is rounded by a post exposure of UV light and a heat treatment. The taper angle of the SnO₂ pattern is controlled by changing the ratio of the sputter etching rate of the AZ-1350J photoresist to the SnO₂ film. This ratio is controlled by oxygen pressure in the atmosphere of the sputtering chamber. The lowest angle of 4 degrees is obtained at 2% oxygen in argon.
The taper-etched SnO₂ film pattern is used as signal electrodes of a trielectrode pickup tube using Se-Te-As chalcogenide glass photoconductor.