Thermal activation of glide in Inp single crystals

The study of the plasticity of undoped indium phosphide between 573 and 1023 K by means of uniaxal compression (epsilon similar or equal to: 10(-4) s(-1)), stress relaxation and transmission electron microscopy shows that the deformation is controlled by the motion of screw dislocations in the stress field of the lattice according to a thermally activated Peierls mechanism. Between 573 and 673 K, this mechanism is pure; it is assisted by the internal stress between 673 and 1023 K and the lattice friction has no effect on the screw dislocations above 1023 K: the deformation is then controlled by the forest mechanism. To move freely in the crystal, a screw dislocation needs an energy below 2.8 eV.