Mechanistic studies of silicon oxidation

The microscopic mechanism of the formation of ultrathin oxides on Si(100) has been investigated using a combination of infrared spectroscopy and ab initio quantum chemical cluster calculations. The 0-->2 monolayer oxide films are grown sequentially from the "bottom-up" using repeated water exposures and annealing cycles, with the partial pressure of water ranging from 10(-10) to 10 Torr. The resultant films were then compared to the equivalent thicknesses of thermal and native oxide films. In this way, we obtain unprecedented insight into the essential chemical structures formed during the initial oxidation and subsequent layer growth of these technologically relevant films. (C) 1999 American Vacuum Society. [S0734-211X(99)02804-8].