Leyla Colakerol, Boston University
on Electronic and Structural Properties of InN

Abstract: Surface morphology of InN films was investigated during growth using real-time synchrotron-based x-ray scattering and x-ray diffraction. The investigated structures were grown by plasma assisted molecular beam epitaxy on sapphire surfaces. 1The detailed studies of the plasma nitridation of c-plane sapphire were performed. 1The surface and bulk electronic properties of InN were investigated using angle resolved photoelectron spectroscopy (ARPES), x-ray absorption spectroscopy and x-ray emission spectroscopy. 1Intrinsic electron accumulation near the surfaces of clean InN was directly observed by ARPES. 1The accumulation layer is discussed in terms of the bulk Fermi level (EF) lying below the pinned surface EF, with a confining potential formed normal to surface due to the downward band bending facilitated by donor type surface states or nitrogen vacancies. 1Intermixing between the heavy and light hole valence bands in the intrinsic quantum well potential associated with the surface electron accumulation layer results in an inverted band structure, with the valence band maximum lying away from the Brillouin zone center.