Effect of annealing temperature on the electrical properties of HfAIO thin films

摘要

High-K gate dielectric HfAlO thin films with different temperature annealing treatment have been deposited on Si substrate by Atomic layer deposition (ALD). The electrical properties of Hf-films are analyzed by measurement of high frequency capacitance-voltage (C-V) and leakage current density-voltage (I-V) characteristics. The electrical measurement results indicate the decrease of equivalent oxide thickness (EOT) due to the great change of microstructure and densification after high temperature annealing and the increase of permittivity. But the interface state density increases. Moreover, the leakage current increases with the increase of annealing temperature. The HfAlO film annealed at 650°C has the best electrical parameters, such as dielectric constant, EOT and leakage current density determined through CV measurement were 23.5, 0.84, 6.8×10~(-7)mA·cm~(-2), respectively.