Structural and electrical analysis of S+ ion bombarded p-InP(100)

The chemical state of sulfur and surface structure on low-energy S+ ion-treated p-InP(100) surface have been investigated by high-resolution X-ray photoelectron spectroscopy (XPS) and low-energy electron diffraction (LEED). S+ ion energy over the range of 10–100eV was used to study the effect of ion energy on surface damage and the process of sulfur passivation on p-InP(100) by S+ ion beam bombardment. It was found that sulfur species formed on the S+ ion-treated surface. The S+ ions with energy above 50eV were more effective in formation of In–S species, which assisted the InP surface in reconstruction into an ordered (1×1) structure upon annealing. After taking into account physical damage due to the process of ion bombardment, we found that 50eV was the optimal ion energy to form In–S species in the sulfur passivation of p-InP(100). The subsequent annealing process removed donor states that were introduced during the ion bombardment of p-InP(100). Results of theoretical simulations by Transport of Ions in Materials (TRIM) are in accordance with those of experiments.