Monte Carlo modeling of wurtzite and 4H phase semiconductor materials

We present a discussion of the complexities encountered in particle simulation models for noncubic symmetry materials, focusing on the wurtzite and 4H phases of semiconductors. We have identified three general issues, band structure, scattering mechanisms, and band intersections, which in our opinion, constitute the most important modifications to Monte Carlo simulators for cubic symmetry materials. Owing to the increased number of atoms and size of the unit cell, the band structure is far more complex in wurtzite and 4H polytypes than in zincblende phase semiconductors. This added complexity is reflected by the greater number of bands, smaller Brillouin zone and concomitant increase in the number of band intersections. We have found that the band intersection points greatly influence the transport dynamics. In this paper, we discuss our initial attempts at treating transport near these points.