Electronic passivation of Si(111) by Ga–Se half-sheet termination

A Si(111):GaSe van der Waals surface is prepared using sequential deposition of Ga and Se at elevated temperature on a Si(111)-7×7 surface. Surface properties were investigated by soft x-ray photoelectron spectroscopy and low-energy electron diffraction. The Si(111)-1×1:GaSe surface remains with electronic surface potentials near flatband condition.