1984 年 5 巻 Special 号 p. 214-219
Electrical conduction in anodized aluminum layers has been studied under various environmental conditions. The anodization was carried out in oxalic acid and sulfuric acid baths. All the oxide layers were found to be amorphous using X-ray diffraction. A thin aluminum film was evaporated onto the oxide layer and thus a sample gas sensor with Al/Al2O3/Al structure was fabricated. Temperature dependences of the conductance of the sample sensors were measured in vacuum in the temperature range from 20°C to 100°C and activation energies for conduction were calculated. The sample sensors showed resistance-decrease associated with vapor adsorption of alcohols such as methylalcohol, ethylalcohol, etc. The sensitivity is higher as a whole with the layers anodized in the oxalic acid solution than with those anodized in the sulfuric acid solution. The conductivitychange associated with thermally stimulated desorption of alcohols was measured, and the desorption behavior of the adsorbate was interpreted in terms of the conductivity-change.