KINETICS OF THE GROWTH OF AL-OXIDIZED FILMS IN A HIGH-FREQUENCY OXYGEN PLASMA

Vacuum-evaporated Al-films on silicon wafer or silica glass substrates that are anodized in a high-frequency oxygen plasma by anodic floatin g and anodic bias oxidation have reflectances up to 93% and 83%, and r efractive indices of 1.22 and 1.45, respectively. The optical properti es of anodically oxidized front surface mirrors depend on the plasma c onditions, temperature and period of exposure to the system oxygen. Fr om measurement of the optical properties of the oxidized films the opt imum conditions were for the Al-film at floating potential at a temper ature between 300 and 350 degrees C and an oxygen exposure of 5-9 x 10 (4)L.