SiC/Si heteroepitaxial growth

Abstract

Mechanistic reaction paths for the heteroepitaxial growth of 3C–SiC on carbonized Si(001) were investigated using a combination of molecular dynamics (MD) simulations, molecular beam epitaxy (MBE), and chemical vapor deposition (CVD) experiments. MD simulations elucidated possible mechanisms of carbonization of 3C–SiC/Si(001) as the shrinkage of the [110] row of the Si lattice atoms with C adatoms. The addition of Si adatoms (ad-Si) to the Si-terminated 3C–SiC(001) 2×1 surface results in formation of a series of surface reconstructions of h×2 where h=…,7, 5, 3 with increasing ad-Si coverage. The most energetically stable 3C–SiC(001) surface was found to be 3×2. The ‘surface-structure-controlled epitaxy’, in which in situ RHEED was used as a feedback signal to adjust JC/JSi during MBE growth to maintain a 3×2 surface reconstruction, on miscut Si(001)-[110] 4° enables the formation of single-phase 3C–SiC with very low density of pit formation, Si bonds, surface crystallites and antiphase boundaries. Additional CVD growth of the ‘surface-structure-controlled epitaxy’ 3C–SiC MBE film on miscut Si(001)-[110] 4° results in the thick single-phase 3C–SiC with smooth surface and little strain at the 3C–SiC/Si interface.