Reactions of I-2 and Cl-2 with In- and As-terminated InAs(001)

The reactions of I-2 and CI2 with InAs(001) were investigated with synchrot ron-based soft-x-ray photoelectron spectroscopy and low-energy electron dif fraction. I-2 saturates the In-terminated InAs(001) surface, forming a well -ordered overlayer of InI, while As-terminated InAs(001) becomes disordered and forms both In and As iodides. Both the In- and As-terminated surfaces are disordered by Cl-2 adsorption, forming InCl, InCl2, and As chlorides. T he differences in the behavior of I-2 and Cl-2 are attributed primarily to the inability of InI2 to form on the outermost surface.