The electrical properties of aluminum silicate (AlSixOy) films grown at 120 and 150 degrees C by plasma-enhanced atomic layer deposition were investigated for the application on flexible devices. AlSixOy films with dielectric constants of 5.6 and 6.8 exhibited a reduced hysteresis voltage in capacitance-voltage curves compared to Al2O3 films, indicating an improved interfacial quality. The leakage current density for AlSixOy is comparable to that for Al2O3. Moreover, the results indicate that the insertion of SiO layers suppresses the film crystallization and the formation of an interfacial layer. (c) 2005 The Electrochemical Society. [DOI: 10.1149/1.2136249] All rights reserved.