Blister formation in He-H co-implanted InP: A comprehensive atomistic study

The blistering efficiency in He-H-ions co-implanted and annealed InP has been found to peak and vanish in a narrow range of ion fluence ratio (?H/?He = 1.5?3.5) with a fixed He fluence of 2 ? 1016 He+/cm2. The blisters are formed at low fluence (?H/?He = 1.5), peaked in the middle (?H/?He = 2.5), and disappeared at the high fluence ratio (?H/?He = 3.5). To get a fundamental understanding of blister formation in nanoscale, the defect profiles were studied by various experimental techniques combined with FEM and ab-initio simulations. Crosssection TEM images showed that at a low fluence ratio, He and H are stored in microcracks and bubbles whereas, at a high fluence ratio, the ions are trapped only inside bubbles. These atomic processes that occur during and after co-implantation and annealing are presented together with detailed scenarios in an attempt to explain our results. Based on DFT simulations, the de-trapping of He atoms from the small clusters is energetically cheaper compared to the migration of He from the large clusters formed at high fluence. Moreover, at a high fluence ratio, the presence of large clusters inhibits the He diffusion to the small clusters (precursor of blisters) by capturing migrating He atoms.

Automated summary

Efficient blistering in He-H-ion co-implanted and annealed InP reaches its peak and disappears within a narrow range of ion fluence ratio, demonstrating different effects on blister formation between low and high fluence ratios. The presence of large clusters inhibits He diffusion to small clusters, impacting the formation of blisters.