Atomic Layer Deposition of HfO2 Films on Ge

We investigated the growth characteristics and interfacial properties of HfO2 films deposited on Ge substrate through atomic layer deposited (ALD) by using an in-situ medium energy ion scattering analysis. The growth kinetics of HfO2 grown on a GeO2/Ge substrate through ALD is similar to that grown on an SiO2/Si substrate. However, the incubation period of HfO2 deposition on Ge is shorter than that on Si. The HfO2 grown on the GeO/Ge substrate shows a significant diffusion of Hf atoms into the substrate interface and GeO volatilization after annealing at 700 degrees C. The presence of low-quality Ge oxide or suboxide may degrade the electrical performance of device.