ELECTRONIC-PROPERTIES OF DISLOCATIONS AND ASSOCIATED POINT-DEFECTS IN GAAS

Effects of plastic deformation on the deep-level spectrum and electronic properties of GaAs single crystals are presented. The deformation creates a high concentration of acceptors. A new level at Ec - 0.68 eV has been identified to be associated with dislocation cores. The level exhibits barrier-limited electron capture and governs the recombination of current carriers. The concentration of the EL6 level is enhanced after the deformation and the rate of the normal-to-metastable transformation of the EL2 centre is slowed. The latter results are discussed in terms of the dislocation-related generation of anti-site defects. The role of the conservative climb in the development of dislocation dipoles in strained crystals is emphasized.