【文章名】Contactless electroreflectance studies of Fermi level position on c-plane GaN surface grown by molecular beam epitaxy and metalorganic vapor phase epitaxy
Contactless electroreflectance studies of Fermi level position on c-plane GaN surface grown by molecular beam epitaxy and metalorganic vapor phase epitaxy
作者
Kudrawiec, R; Gladysiewicz, M; Janicki, L; Misiewicz, J; Cywinski, G; Cheze, C; Wolny, P; Prystawko, P; Skierbiszewski, C
[摘要]：Contactless electroreflectance (CER) has been applied to study the Fermi-level position on c-plane GaN surface in Van Hoof structures grown by molecular beam epitaxy (MBE) and metalorganic vapor phase epitaxy (MOVPE). A clear CER resonance followed by strong Franz-Keldysh oscillation (FKO) of various periods was clearly observed for the series of samples of different thicknesses (30, 50, and 70 nm) of undoped GaN layer. The built-in electric field in this layer has been determined from the period of GaN-related FKO. A good agreement between the calculated and measured electric fields has been found for the Fermi-level located similar to 0.4 and similar to 0.3 eV below the conduction band for the MBE and MOVPE samples, respectively. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4707386]
