著者
Sakurai Yoko Kakushima Kuniyuki Ohmori Kenji Yamada Keisaku Iwai Hiroshi Shiraishi Kenji Nomura Shintaro
出版者
Optical Society of America
雑誌
Optics Express (ISSN:10944087)
巻号頁・発行日
vol.22, no.2, pp.1997-2006, 2014-01
被引用文献数
3

Low-temperature photoluminescence (PL) spectra of electron-hole systems in Si nanowires (NWs) prepared by thermal oxidization of Si fin structures were studied. Mapping of PL reveals that NWs with uniform width are formed over a large area. Annealing temperature dependence of PL peak intensities was maximized at 400 °C for each NW type, which are consistent with previous reports. Our results confirmed that the micro-PL demonstrated here is one of the important methods for characterizations of
著者
Sato Soshi Li Wei Kakushima Kuniyuki Ohmori Kenji Natori Kenji Yamada Keisaku Iwai Hiroshi
出版者
American Institute of Physics
雑誌
Applied physics letters (ISSN:00036951)
巻号頁・発行日
vol.98, no.23, pp.233506, 2011-06
被引用文献数
9

Interfacial states of silicon nanowire field-effect transistors with rectangular-like cross-sections (wire height of 10 nm and widths of 9 and 18 nm) have been evaluated from the transfer characteristics in the subthreshold region measured at cryogenic temperatures, where kinks in the drain current becomes prominent. It is found that the kinks can be well-explained assuming local interfacial states near the conduction band (Ec). The main extracted local states have been shown to exist at 10 and 31 meV below Ec with the densities of 1.3×1013 cm−2/eV and 5.4×1012 cm−2/eV, respectively. By comparing two field-effect transistors with different wire widths, the former states can be assigned to the states located at the corner and the side surface of the wire, and the latter to the top and the bottom surfaces.
著者
Kita Yuki Yoshida Shinichi Hosoi Takuji Shimura Takayoshi Shiraishi Kenji Nara Yasuo Yamada Keisaku Watanabe Heiji
出版者
American Institute of Physics
雑誌
Applied physics letters (ISSN:00036951)
巻号頁・発行日
vol.94, no.12, pp.122905, 2009-03
被引用文献数
8 8

Change in the work function (WF) of the gate electrode material caused by the contact with Hf-based high-k gate dielectrics was investigated by means of the flat-band voltage (Vfb) shift in capacitance-voltage curves, and the interface dipole, which modifies the WF, was characterized by x-ray photoelectron spectroscopy. We observed a negative Vfb shift and corresponding interface dipole, which suggest the formation of oxygen vacancy (VO) in the Hf-based oxides. In contrast, we observed an opposite (positive) Vfb shift and interface dipole when Au electrodes were formed on cleaned Hf-based dielectrics. This indicates that Au–Hf bond hybridization at the Au/HfSiON interface also causes effective WF modulation, as theoretically predicted by Shiraishi et al. (Tech. - Dig. Int. Electron Devices Meet. 2005, 43).