Electrical properties of surface and interface layers of the N- and In-polar undoped and Mg-doped InN layers grown by PA MBE

Abstract

Electrical properties of N-polar undoped and Mg-doped InN layers and In-polar undoped InN layers grown by plasma-assisted molecular beam epitaxy (PA MBE) were studied. Transport parameters of the surface and interface layers were determined from the measurements of the Hall coefficient and resistivity as well as the Shubnikov-de Haas oscillations at magnetic fields up to 60T. Contributions of the 2D surface, 3D near-interface and 2D interface layers to the total conductivity of the InN films were defined and discussed as dependent on InN surface polarity, Mg doping and PA MBE growth conditions.

Plasma-Assisted Molecular Beam Epitaxy of In-Rich InGaN: Growth Optimization for Near-IR Lasing

“…2 and 1c, a certain correlation is clearly seen between the measured SE threshold and the electrical conductivity of the InGaN layers studied, and it is well established that the electron concentration in the active layer affects the SE threshold (e.g., 14 ). However, it appears very common for InN and In-rich InGaN that the layer conductivity does not directly reflect the relevant carrier concentration, since both InN/GaN interface and InN free surface are known to provide additional free electrons and thus contribute significantly into the electrical properties of epitaxial InN films (e.g., [35][36][37][38]. Sandwiched between these "interface" regions, there is relatively pure "bulk" InN (InGaN) with a much lower electron concentration, which is apparently responsible for light emission.…”