Investigation of native oxide growth on zinc in different atmospheres by spectroscopic ellipsometry

Abstract

AbstractThe native oxide layer formed spontaneously on the surface of metallic Zn was investigated by in situ spectroscopic ellipsometry (SE) and ex situ X‐ray photoelectron spectroscopy (XPS). XPS analysis shows the coexistence of hydroxide and oxide in the oxide film. The growth kinetics of the oxide films in different atmospheres was measured in a specially designed optical cell. The growth in O2, Ar and air at high (>95%) and low (<10%) relative humidity was monitored for up to 72 h. Differences in the growth kinetics of the films are observed in different atmospheres. In argon, growth in layer thickness is limited. In oxygen, one obtains a growth with a fast initial phase followed by a linear second phase with a growth rate of ≈0.01 nm h−1. The electronic structure of the layer changes rapidly at the beginning of exposure of the surface to the respective atmosphere, with no further changes observed during the experiment. magnified image