LAUSR

Abstract Dielectric Al2-xSixOy (X = 0.00, 0.02, 0.05, 0.10) thin films were deposited onto Pt/Ti/SiO2/Si substrates using sol-gel spin coating technology. The obtained materials were characterized via differential scanning calorimetry (DSC), scanning electron microscopy (SEM), fourier transform infrared spectrometry (FT-IR) and X-ray photoelectron spectrometry (XPS). The results show that the films are amorphous with Si atoms occupying Al atom sites forming Al O Si bonds and glass-like structure. The dielectric properties of the film were investigated. By means of silicon doping, the leakage current and the dielectric loss of the amorphous alumina films much reduced while the breakdown strength enhanced. Two orders of magnitude reduction in leakage current and significant enhancement in breakdown strength (up to 566 MV/m) can be achieved. The improved dielectric properties are attributed to the forming of Al O Si bonds and cation vacancies by the Si-addition. The structure modification enhanced the stability of alumina structure and promoted the ionic transportation to repair the defects of the alumina films.