Fig. 11From: High speed silicon wet anisotropic etching for applications in bulk micromachining: a reviewSEM images of 1 μm wide deep grooves showing the comparison of etch uniformity under three etching conditions in 41 wt% KOH at 60℃ for 6 h: a no agitation, b ultrasonic agitation with a single frequency of 28 kHz, and c ultrasonic agitation with 28, 45, 100 kHz frequencies applied sequentially for 1 ms duration [83], © 1995, IEEEBack to article page