Effect of impurity doping on 4H-SiC planarization

Silicon carbide (SiC) is a next-generation wide-gap semiconductor material, but its high hardness and brittleness limit cost reduction and quality promotion. The planarization at the packaging stage faces the doped SiC wafer, thus understanding the effect and behaviors of impurity during planarization is necessary for the final packaging performance. In this study, a series of models with various doping types (Al, B, N, P) and concentrations (10
¹⁸
cm
^-3
– 10
²⁰
cm
^-3
) were constructed to simulate based on molecular dynamics. The machinability effect and dynamic features of impurity were focused on in the analysis of the results. The results revealed that heavy doping affects the machinability on the nano-scale and N doping has better machinability than the other types of impurity. In addition, a potential competition mechanism between the solution strengthening and cohesive weakening maybe exist, resulting in the differences among various impurity types.