Modelling of the plastic behaviour of III–V compound semiconductors during compressive tests

An extension of the Haasen–Alexander model to the case of III–V semiconductor compounds with sphalerite structure is presented. With the extended model it is possible to simulate with a reasonable degree of accuracy their plastic behaviour in the low temperature range. Macroscopic stress–strain characteristics are described quantitatively in terms of the dislocation glide dynamics. The activation of three types of perfect dislocations distinguished in compound semiconductors is taken into account. With the experimentally determined dislocation mobilities, the model fails to describe the crystal plasticity below some critical temperature. This suggests that the experimentally observed abrupt change in the variation of the yield stress with temperature is related to a change in the controlling microscopic mechanisms.