Modification of Silicon Dioxide by Hydrogen and Deuterium Plasmas at Room Temperature

Abstract

Silicon dioxides exposed to H2 and D2 plasmas have been investigated using X-ray photoelectron spectroscopy and secondary ion mass spectrometry. D2 plasma exposure at the self-bias voltage of 230 V results in reduction of Si on the SiO2 surface, but not in the H2 plasma exposure at the same self-bias voltage. This difference between the D2 and H2 plasma exposures is attributable to the larger momentum transfer effect of the deuterium ions. The hydrogen or deuterium atoms incorporated diffuse through the SiO2 film during the plasma exposure and pile up at the Si-SiO2 interface.