Title: Deep levels, electrical and optical characteristics in SnTe-doped GaSb Schottky diodes
Authors: Chen, JF
Chen, NC
Liu, HS
National Chiao Tung University
Department of Electrophysics
Keywords: deep levels;GaSb Schottky diodes;Hall measurement;photoluminescence (PL);SnTe dopants
Issue Date: 1-Nov-1996
Abstract: The GaSb layers investigated were grown directly on GaAs substrates by molecular beam epitaxy (MBE) using SnTe source as the n-type dopant. By using admittance spectroscopy, a dominant deep level with the activation energy of 0.23-0.26 eV was observed and its concentration was affected by the Sb-4/Ga flux ratio in the MBE growth. A lowest deep-level concentration together with a highest mobility was obtained for GaSb grown at 550 degrees C under a Sb-4/Ga beam equivalent pressure (BEP) ratio around 7, which should correspond to the lowest ratio to maintain a Sb-stabilized surface reconstruction. In the Hall measurement, an analysis of the temperature-dependent mobility shows that the ionized impurity concentration increases proportionally with the sample's donor concentration, suggesting that the ionized impurity was introduced by an SnTe source. In addition, optical properties of an undoped p-, a lightly and heavily SnTe-doped GaSb layers were studied by comparing their photoluminesence spectra at 4.5K.
URI: http://hdl.handle.net/11536/948
ISSN: 0361-5235
Volume: 25
Issue: 11
Begin Page: 1790
End Page: 1796
Appears in Collections:Articles