DEEP LEVELS CAUSED BY MISFIT DISLOCATIONS IN GAASSB GAAS HETEROSTRUCTURES/

Two deep electron traps induced by lattice mismatch in relaxed GaAs1-x Sbx layers (x=0% to 3%) grown by liquid phase epitaxy (LPE) on GaAs su bstrates have been revealed by means of deep-level transient spectrosc opy. One of the traps, that shows nonstandard, logarithmic capture kin etics and whose energy level is tied to the valence-band edge, has bee n related to electron states associated with ct dislocations. The othe r trap has been attributed to the EL2 defect and possible reasons of i ts unexpected formation in the LPE-grown layers are briefly discussed. (C) 1995 American Institute of Physics.