Arsenic-doped CdTe epilayers grown by photoassisted molecular beam epitaxy

Abstract

We report the successful p-type doping of CdTe films with arsenic using the photoassisted molecular beam epitaxy growth technique. These doped epilayers were grown at substrate temperatures as low as 180°C. The room-temperature hole concentrations in the CdTe:As layers ranged from 7×10 15 to 6.2×1018 cm -3 as determined by van der Pauw-Hall effect measurements. We propose a doping mechanism responsible for the high p-type doping levels observed in the films. The arsenic acceptor ionization energy was found to ∼58-60 meV using low-temperature photoluminescence measurements.