Triboelectric current generation by friction of conductive probe and GaAs surface

Generation of triboelectric current during friction of a conducting probe against a GaAs surface with a layer of native oxide has been studied. It is shown that the triboelectric current in GaAs is two orders of magnitude higher than the current in Si and the direction of the current is determined by the difference in the work function between the probe and the GaAs surface. The increase in triboelectric current in GaAs compared to Si is due to the high density of surface states and the tunneling of electrons from the probe onto them during friction.