Investigation of electrodischarge micromachining controllable factors on machined silicon surface quality

Abstract

Electrodischarge micromachining (micro-EDM) is a prospective technology for the micromachining of conductive and even semi-conductive materials. However, there remain a number of application problems, particularly in relation to the understanding and control of the effect of micro-EDM controllable factor interaction on surface integrity in machining silicon. This study investigates the effect of the interaction of micro-EDM parameters, such as the rotary action of the tool electrode and discharge energy levels, on the surface integrity of a p-type boron-doped silicon wafer. Empirical models are formulated that adequately describe the effects of discharge energy on the average surface roughness and the area fraction voids. Subsequently, the nature and causes of micro-EDM surface and subsurface characteristics are discussed on the basis of scanning electron microscope and X-ray energy dispersive spectrometer analysis. This provides useful information for controlling the input process parameters to obtain smooth finished surfaces.