High-quality GeON Gate Dielectrics formed by Plasma Nitridation of Ultrathin Thermal Oxides on Ge(100)
High-quality germanium oxynitride (GeON) gate dielectrics for Ge-based metal-oxide-semiconductor (MOS) devices were fabricated by plasma nitridation of ultrathin thermal oxides on Ge(100) substrates. Although ultrathin oxides with abrupt GeO2/Ge interfaces can be formed by conventional dry oxidation, air exposure results in serious electrical degradation. It was found that plasma nitridation forms a nitrogen-rich capping layer on the ultrathin oxide and significantly improves thermal stability of the GeON layer. The nitrogen-rich layer effectively suppresses electrical degradation during air exposure and provides excellent insulating properties. Consequently, we were able to achieve Ge-MOS capacitors with GeON dielectrics of an equivalent oxide thickness (EOT) as small as 1.7 run. Minimum interface state density (Dit) values of GeON/Ge structures, i.e., as low as 3 x 10 cm-2eV-1, were successfully obtained for both the lower and upper halves of the bandgap.
Heiji Watanabe Katsuhiro Kutsuki Iori Hideshima Gaku Okamoto Takuji Hosoi Takayoshi Shimura
Department of Material and Life Science, Graduate School of Engineering, Osaka University 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
国际会议
上海
英文
867-870
2010-11-01（万方平台首次上网日期，不代表论文的发表时间）