Surface characteristics of micro-ultrasonically machined (1 0 0) silicon

Micro-ultrasonic machining of single crystal silicon was performed using 0.1 and 0.25μm diamond abrasives and a 200μm diameter cemented carbide cylindrical tool. The depth of cut was varied from 200 to 1400 nm and the average surface roughness was found to be 5–15 nm Sa. Confocal Raman microscopy of the cut surface indicated the presence of both diamond cubic and amorphous phases of silicon.