It was shown that, in undoped semi-insulating crystals which were grown under stoichiometric conditions, correlated and anti-correlated dependences of the minority carrier lifetime upon the dislocation density could be observed. These effects were related to a slight excess of Ga atoms (where a correlated dependence of carrier lifetime upon dislocation density appeared) or of As atoms (where an anti-correlated dependence of carrier lifetime upon dislocation density appeared). These were expected to be inevitable even in ostensibly stoichiometric crystals.

K.D.Glinchuk, A.V.Prokhorovich: Crystal Research and Technology, 1995, 30[4], 531-4