Patent ID: 7198727

Claim:
A method for micromachining <100> silicon, comprising: (a) defining three areas of a substrate: an unetched area, a dry etch area, and a wet etch area, wherein the dry etch area and the wet etch area are adjacent; (b) forming an SiO 2 layer over the unetched and wet etch areas of a substrate, forming silicon nitride on the SiO 2 in the wet etch area, wherein the dry etch area is uncovered; (c) dry etching the dry etch area to form a dry-etched pit; (d) oxidizing the substrate to form a SiO 2 layer in the dry-etched pit; (e) removing the silicon nitride and thinning the SiO 2 to expose the wet etch area; and (f) wet etching the wet etch area.