Digital Chemical Vapor Deposition of SiO₂ Using a Repetitive Reaction of Triethylsilane/Hydrogen and Oxidation

Abstract

The extraction reaction of hydrogen in triethylsilane (TES) with hydrogen radicals generated by a remote plasma of H 2 produces an organic Si film. Step coverage features of the film depend strongly on H 2 concentration in the TES+H 2 reaction system. A conformal profile has been achieved for 60% H 2 at 250°C as a result of the low-viscosity nature of the film which includes C x H y groups. With the aim of filling a deep trench with hlgh-quality SiO 2 film, digital chemical vapor deposition (CVD), which was carried out by repeating a cycle of the conformal deposition of the Si film and subsequent oxidation, was studied. The SiO 2 film which was deposited at 250°C and with an initial thickness per cycle of 5 Å at a 1 s oxygen pulse offered a low concentration of organic species, and thus a relatively low BHF etch rate.