Kinetic Investigations of the Initial Oxidation Stage of Copper by In-Situ UHV-TEM

Abstract

ABSTRACTWe have examined the nucleation and growth of copper oxides formed by in-situ oxidation of copper thin films inside a modified transmission electron microscope (TEM). Based on this data, we have developed a semi-quantitative model of the initial oxidation stage where the dominant mechanism for transport, nucleation and growth of oxide islands is oxygen diffusion on the surface. The copper oxide can be desorbed by annealing and introducing methanol vapor into the chamber. The clean copper film can be oxidized by introducing oxygen gas. Both the desorption and oxidation processes were observed by planar TEM techniques. The copper film was oxidized in-situ at a partial pressure of 5×104torr. Cu2O islands, which formed epitaxially to the copper film, nucleated and grew into the copper film.