International Journal of Advances in Computer Science and Its Applications
Author(s) : TAKESHI TOKOROZUKI, TOMO UENO , YOSHITAKA IWAZAKI
Currently, as next - generation MOS devices, a high-k/Ge structure, which has high electron and hole mobility than that of Si, and has the ability to low power consumption during device operation has been expected. Although HfO2 which exhibits excellent characteristics on silicon can be applied as high-k material, it is known that Ge and HfO2 cause diffusion of atoms due to heat treatment during device fabrication process and deteriorate electric characteristics such as large leakage current in HfO2 film and large interface trap density at the HfO2/Ge interface. Therefore, lower fabrication process temperature has been attempted by introducing Kr/O2 plasma oxidation instead of conventional thermal oxidation method in this research. As a result, compared to thermal oxidation, the leakage current is greatly reduced and the electrical characteristics are drastically improved by using Kr/O2 plasma oxidation. Therefore, we can conclude that high quality HfO2 can be formed on Ge substrates, and that interface defects and traps in the film have been successfully suppressed using Kr/O2 plasma oxidation method.