Band offsets in c-Si/Si-XII heterojunctions

Silicon has a rich phase diagram with a multitude of phases existing over a wide range of pressures and temperatures, in addition to the common cubic silicon (c-Si) phase. One such phase, Si-XII, was first observed less than 2 decades ago in diamond anvil experiments, and more recently as a product of nanoindentation. In some of these latter experiments, I–V measurements were performed to characterize the c-Si/Si-XII interface that results when Si-XII is formed in cubic silicon substrates. In this paper we describe calculations of the band offsets in c-Si/Si-XII heterojunctions. We find that the heterojunction is of Type I and that the band offsets are estimated to be Δ E v = 0.3 eV and Δ E c = 0.5 eV for the valence bands and conduction bands, respectively.