Thin‐Film Studies of the Reduction of SiO 2 by Al

The reaction between Al and SiO 2 at 700° to 850°C was examined under high vacuum using thin Al films on SiO 2 plates. The reaction products were analyzed by electron diffraction. The only nongaseous reaction product was Si, which was observed only when the reaction was conducted at a pressure low enough to inhibit the oxidation of Si to a gaseous product, presumably SiO. The reaction was very rapid, and the dwell time observed in bulk by Standage and Gani was apparently absent. The activation energy of the reaction is 17±4 kcal/mol.