Atomic-layer-deposited (HfO₂)1−x(Al₂O₃)x nanolaminate films on InP with different Al₂O₃ contents

The effect of Al 2 O 3 mixing in HfO 2 on the electrical properties was studied on InP substrates using nanolaminate films grown by atomic layer deposition. The In out-diffusion and the subsequent In-related oxide phase generation were effectively suppressed by introducing more Al 2 O 3 to the HfO 2 film. Although the decrease in the maximum capacitance was taken into consideration, more Al 2 O 3 introduction significantly improved the dielectric properties. The magnitude of the capacitance–voltage frequency dispersion was decreased with the reduced border trap and interface state densities. Additionally, the leakage current characteristics were improved, including the voltage-stress-dependent reliability.