Effect of organic contaminants on the oxidation kinetics of silicon at room temperature

Abstract

The oxidation kinetics of HF-etched n- and p-doped silicon in air at room temperature have been studied by electron spectroscopy for chemical analysis. No great differences have been found between the n- and p-type oxidation kinetics at the low doping level of the studied samples. The rate of oxide growth on the HF-etched surface is much lower than that on a silicon surface obtained by fracture in air of a silicon monocrystal. The behavior of a silicon sample fractured in de-ionized water and then oxidized in air at room temperature is intermediate. The above findings have been interpreted on the basis of surface reactions involving the plasticizers of the HF and water containers. These reactions produce carbon-rich hydrophobic surfaces which retard the silicon oxide growth. A mechanism for the involved surface reactions is proposed.