Low-temperature magnetotransport measurements have been performed to study the spatial distribution of conduction electrons near a (111)B surface of p-type InAs damaged during a SiO 2 -sputtering process. The results obtained for both the in-plane and perpendicular magnetic field orientations are well explained by a two-layer model. The electron density of a three-dimensional electron layer, having submicron thickness, decreases rapidly with an increase in annealing temperature and the conduction is eliminated after annealing above 125°C. On the other hand, the conduction of a two-dimensional electron layer at the surface remains after annealing.