Properties of aluminum titanate films prepared by chemical vapor deposition under different aluminum butoxide inputs

Properties of amorphous aluminum titanate films prepared by low-pressure chemical vapor deposition using a mixture of aluminum tri-sec-butoxide, titanium tetrachloride, CO2, and H2, have been investigated. The higher compressive internal stress is attributed to the films with a thinner thickness. The scratch resistance of the film is strongly related to the internal stress. Some 350 °C-deposited films have a defected structure with high dielectric constants of 230-320. Resistivity above 1011 Ω cm can be obtained for the as-deposited films. Breakdown voltages increase slightly with substrate temperature and were in the range of 1.6-4.9 MV/cm. Refractive indices are in the range of 1.71-2.20. Annealing does not improve the dielectric and electrical properties. Optical transmittance and its spectral modulation are strongly related to the film thickness.