Crucial roles of holes in electronic bond rupture on semiconductor surfaces

Structural changes on cleaved (110) surfaces of InP, induced by tunneling carriers from the tip of a scanning tunneling microscope, were studied. Bond rupture takes place at intrinsic P-sites only at negative sample voltages (i.e., under hole-injection conditions), resulting in the formation of P-vacancies, while injected electrons induce no structural change. The rate of bond rupture, showing a prominent threshold sample voltage at − 2.2 V, is a quadratic function of the tunneling current. Nonlinear localization of two holes injected into surface bands is crucial as the primary step in the electronic bond rupture on semiconductor surfaces.