Evaluation of the oxidation of TiO_(2) films during reactive evaporation of Ti_(3)O_(5) and during exposure of the films to the atmosphere

摘要

A surplus amount of oxygen is needed to produce titanium dioxide films by reactive electron-beam evaporation of Ti_(3)O_(5). We investigated the ratio of the rates at which oxygen molecules and TiO_(x) molecules impinge upon substrates at 25° and 250℃ to produce TiO_(2) films that show no optical absorption in the visible spectral region. On unheated substrates the ratio was 49, and at 250℃ it was 26, provided that the substrates had been exposed to air after being coated at the given substrate temperature. Higher ratios were required if the TiO_(2) film was covered with a SiO_(2) film, which impeded further oxidation. Furthermore, the postdeposition oxidation behavior of these films was studied.