Growth of SiO 2 at Room Temperature with the Use of Catalyzed Sequential Half-Reactions

Abstract

Films of silicon dioxide (SiO ₂ ) were deposited at room temperature by means of catalyzed binary reaction sequence chemistry. The binary reaction SiCl ₄ + 2H ₂ O → SiO ₂ + 4HCl was separated into SiCl ₄ and H ₂ O half-reactions, and the half-reactions were then performed in an ABAB … sequence and catalyzed with pyridine. The pyridine catalyst lowered the deposition temperature from >600 to 300 kelvin and reduced the reactant flux required for complete reactions from ∼10 ⁹ to ∼10 ⁴ Langmuirs. Growth rates of ∼2.1 angstroms per AB reaction cycle were obtained at room temperature for reactant pressures of 15 millitorr and 60-second exposure times with 200 millitorr of pyridine. This catalytic technique may be general and should facilitate the chemical vapor deposition of other oxide and nitride materials.