Abstract
The dependence of room-temperature oxidation of silicon catalyzed by Cu 3 Si on silicide thickness, silicide grain size and the substrate orientation has been investigated by transmission electron microscopy (TEM), X-ray diffractometry and Auger electron spectroscopy. The extent of oxidation was found to depend critically on the starting film thickness of Cu 3 Si. The oxidation was found to be more restricted on (111)Si than that in (001)Si samples. The SiO 2 layer thickness was found to decrease with the average grain size of the starting Cu 3 Si layer. High-resolution TEM revealed that the oxidation is initiated at the grain boundaries. An oxide film as thick as 4.5 μm was grown at room temperature over a period of two weeks in (001) samples. The growth of the thick oxide film was achieved by minimizing the grain size of Cu 3 Si through a reaction between Cu and an intermediate amorphous silicon layer at 200 °C. Mechanisms for catalytic oxidation of silicon in the presence of Cu 3 Si are discussed. © 1995.