Capacitance study of electron traps in low-temperature-grown GaAs

P. N. Brunkov (1) , A. A. Gutkin (1) , A. K. Moiseenko (1) , Yu. G. Musikhin (1) , V. V. Chaldyshev (1) , Nikolay Cherkashin (2, 1) , S. G. Konnikov (1) , V. V. Preobrazhenskii (3) , M. A. Putyato (3) , B. R. Semyagin (3)

1 A.F. Ioffe Physical-Technical Institute
2 CEMES-MEM - Matériaux et dispositifs pour l'Electronique et le Magnétisme
3 Institute of Semiconductor Physics, Novosibirsk

Electron traps in GaAs grown by MBE at temperatures of 200–300°C (LT-GaAs) were studied. Capacitance deep level transient spectroscopy (DLTS) was used to study the Schottky barrier on n-GaAs, whose space-charge region contained a built-in LT-GaAs layer ∼0.1 µm thick. The size of arsenic clusters formed in LT-GaAs on annealing at 580°C depended on the growth temperature. Two new types of electron traps were found in LT-GaAs layers grown at 200°C and containing As clusters 6–8 nm in diameter. The activation energy of thermal electron emission from these traps was 0.47 and 0.59 eV, and their concentration was ∼1017 cm−3, which is comparable with the concentration of As clusters determined by transmission electron microscopy. In LT-GaAs samples that were grown at 300°C and contained no arsenic clusters, the activation energy of traps was 0.61 eV. The interrelation between these electron levels and the system of As clusters and point defects in LT-GaAs is discussed.

Domaines: Physique [physics]

P. N. Brunkov, A. A. Gutkin, A. K. Moiseenko, Yu. G. Musikhin, V. V. Chaldyshev, et al.. Capacitance study of electron traps in low-temperature-grown GaAs. Semiconductors, 2004, 38 (4), pp.387--392. ⟨10.1134/1.1734663⟩. ⟨hal-01736105⟩