The electronic structure and stoichiometric characteristics of postnitrided HfO2 grown on Ge(100) were investigated by various physical measurements. N incorporation in HfO2 grown on Ge was strongly related to the diffusion of Ge from Ge substrate into the film by the postannealing treatment in an NH3 ambient. The diffusion of Ge into the HfO2 film was influenced by the formation of GeOx and GeOxNy in the interfacial region. The small amount of N was incorporated into the film at a nitrided temperature of 600°C, while much larger amounts of N atoms were incorporated into the interfacial layer to form GeON at a temperature of 700°C, resulting in the suppression of the diffusion of Ge into the film. However, the interfacial nitrided layer was not stably maintained during the postnitridation anneal, resulting in an enhanced interdiffusion of Ge and Hf into the film.
Bibliographical noteFunding Information:
This work was partially supported by the System IC 2010 and the National Program for Tera-level Nanodevices of the Ministry of Science and Technology as one of the 21st Century Frontier Programs.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)