The effect of dislocation nature on the size effect in Indium Antimonide above and below the brittle-ductile transition

J. M. Wheeler; L. Thilly; Y. Zou; A. Morel; R. Raghavan; J. Michler

MRS Advances 5 (2020) 1811-1818

The effect of length scale on mechanical strength is a significant consideration for semiconductor materials. In III-V semiconductors, such as InSb, a transition from partial to perfect dislocations occurs at the brittle-to-ductile transition temperature (∼150 °C for InSb). High temperature micro-compression reveals InSb to show a small size effect below the transition, similar to ceramics, while in the ductile regime it shows a size effect consistent with fcc metals. The source truncation model is found to agree with the observed trends in strength with size once the change in Burgers vector and bulk strength are taken into account.