The physical and electrical effects caused by interfacial reactions of HfO 2 on Si-passivated GaAs were investigated by various methods. The results showed that the Si layer decreases the diffusion and formation of GaO. Moreover, post-nitridation in HfO 2 /Si/GaAs significantly reduced the formation of AsO and GaO. The depth profiling data showed that two separated layered structures were formed with HfO 2 and a mixture of HfO 2 and SiO 2 after the annealing process. The crystalline structure and formation of GaO in the film affect the band offsets between GaAs and the high-k HfO 2 dielectric. Moreover, the Si passivation effectively suppressed the interfacial defects caused by GaO diffusion during the annealing treatment. The nitridation cause As diffusion to oxygen vacancy of HfO 2 result in the increase of the interfacial defect.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Physics and Astronomy(all)
- Surfaces and Interfaces
- Surfaces, Coatings and Films