High-stress deformation of GaAs

Abstract

It is shown that GaAs can be deformed under high stress at temperatures as low as 150°C. The resulting dislocation structure consists of straight, dissociated dislocations lying along ⟨110⟩ Peierls valleys. Screw dislocations are found to predominate. The dislocations can move during irradiation in the transmission electron microscope even when the temperature of the specimen is cooled to below −100°C. It is argued that this motion is primarily due to electron-hole recombination enhancement of the dislocation mobility since the dislocations remain in the as-stressed state for long period at room temperature. The mobility of α-dislocations is by far the greatest; when such dislocations could be observed, it was found that their velocity could exceed 10⁻⁴cms⁻¹. Asymmetric motion of both 60°-β-dislocations and dissociated screw dislocations was also directly observed.