Comparison study of different fluorine sources for F-enhanced oxidation of silicon

Several investigators observed that a small amount of fluorine-bearing chemicals (in the ppm range) can cause a dramatic enhancement in the oxidation rate of silicon. In this study, various physical properties of different fluorine sources, such as vapor pressure, were explored and compared for potential application in device processing of submicrometer feature structures. Their ease of delivery into the oxidation system was given special consideration, along with their enhancement effect on oxide growth. Furthermore, dry and ``slightly wet{''} fluorinated oxidation processes were studied, with emphasis on comparing the uniformity of oxide thickness in a large-scale industrial oxidation system. The thermodynamic modeling of the reactant inside the oxidation furnace using SOL-GAS software was conducted, and it provided a basis for interpreting and discussing the experimental results. (C) 1999 The Electrochemical Society. S1099-0062(98)06-023-4-X. All rights reserved.