Kinetic Monte Carlo simulation of void swelling in GaSb irradiated with Sn at low temperature

Large void formation (10% swelling) has recently been observed experimentally near the (1 0 0) surface of GaSb upon Sn ion implantation at 6 dpa below 140 K. In this paper, the accumulation of vacancies is studied by kinetic Monte Carlo simulation. In order to achieve a large swelling, the following conditions have to hold. (1) In the absence of antisite defect formation, the initial distribution diameters of vacancies and interstitials in the cascade are 40a and 44.5a, respectively, where a is the lattice constant of GaSb. (2) In the case of antisite defect formation, the corresponding initial distribution diameters are 40a and 46a, respectively. Vacancy migration is assumed to be radiation-induced. Although second nearest neighbor hopping and vacancy pair migration models are tested for void migration, no large difference is detected in the swelling.