Removal behavior of micropipe in 4H-SiC during micromachining

Abstract

Silicon carbide is a sound semiconductor material because of its good performance in high-voltage and high-frequency fields. However, micropipe — a special 3 dimensions defect commonly is introduced at the epitaxial growth stage — is easy to be passed to the machining stage, and deteriorates the final device performance. In the current work, we employ micromachining atomistic simulations with a single abrasive particle to evaluate whether these defects are eliminated by varying the penetration depth. The simulation results are analyzed from the aspects of structure and energy, atomistic flow field, stress distribution, and temperature; the behavior models of the finished groove are proposed. By these analyses, it is found that it seems to be impossible to completely eliminate the effect of the micropipe by adjusting the penetration depth during micromachining, based on our MD simulation cases; but 4H-SiC shows different dynamic behaviors under different penetration depths, which may be a strategy to detect or control the effect of micropipe. • 4H-SiC micromachining atomistic model with the micropipe defect was constructed. • Completely eliminating the effect of micropipe by adjusting penetration depth was proven to be impossible by MD simulation. • Behavior models of the finished groove were summarized. • Strategy to detect or control the effect of micropipe was proposed.