Clustering in gallium ion beam sputtered compound materials driven by bond strength and interstitial/vacancy reaction

The investigation of chemical reactions during ion irradiation is a frontier for the study of the ion–material interaction. In order to probe the chemistry of ion produced nanoclusters, valence electron energy loss spectroscopy (VEELS) was exploited to investigate Ga+ ion damage in Al2O3, InP, and InGaAs, where each target material has been shown to react differently to the interaction between impinging ions, recoil atoms, and vacancies: metallic Ga, ternary InGaP clusters, and metallic In clusters are formed in Al2O3, InP, and InGaAs, respectively. Supporting simulations based on Monte Carlo and crystal orbital Hamiltonian calculations indicate that the chemical constitution of cascade induced nano-precipitates is a result of a competition between interstitial/vacancy consumption rates and preferential bond formation due to differing bond strengths.