Beam flux dependence of ion-irradiation-induced porous structures in III–V compound semiconductors

Beam flux dependence of ion-irradiation-induced porous structures in GaSb and InSb were studied by focused ion beam. The void and elevation structure were formed after irradiation. The average diameter of the void was approximately 42 nm in the sample irradiated to a flux of 4×1017 ions/m2s and 61 nm in the sample irradiated to a flux of 30×1017 ions/m2s in GaSb in a total fluence of 20×1018 ions/m2. It is considered that many vacancies are immediately induced in the sample of high-flux irradiation. Therefore, the diameter of the void in high-flux irradiation is larger than it is in low-flux irradiation.