Abstract
We studied the influence of applied bias on of the Vickers microhardness HV 0.025 of CdZnTeSe and CdZnTe semi-insulating samples without and with the illumination of light at 870 nm. We observed that a small applied bias results in the hardening of the material.
The effect is strongest at a bias of +/- 0.5 V and is further strengthened by additional illumination. We suggest that the observed positive electro and electro-photo plastic effects in CdZnTeSe and CdZnTe can be explained by an increase in the concentration of free electrons and holes injected from contacts in a biased sample or generated by illumination.
These free carriers can be trapped at dislocations and induce a reconstruction of bonds at the dislocation core. The necessity to break the bonds before dislocation glide results in an increase of microhardness.