Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Hosoi, Takuji*; Kirino, Takashi*; Uenishi, Yusuke*; Ikeguchi, Daisuke*; Chanthaphan, A.*; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; et al.
Workshop digest of 2012 Asia-Pacific Workshop on Fundamentals and Applications of Advanced Semiconductor Devices (AWAD 2012), p.22 - 25, 2012/06
Hosoi, Takuji*; Kirino, Takashi*; Chanthaphan, A.*; Uenishi, Yusuke*; Ikeguchi, Daisuke*; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; et al.
Materials Science Forum, 717-720, p.721 - 724, 2012/05
Times Cited Count:5 Percentile:90.61(Materials Science, Multidisciplinary)Watanabe, Heiji*; Hosoi, Takuji*; Kirino, Takashi*; Uenishi, Yusuke*; Chanthaphan, A.*; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; et al.
Materials Science Forum, 717-720, p.697 - 702, 2012/05
Times Cited Count:2 Percentile:72.03(Materials Science, Multidisciplinary)Watanabe, Heiji*; Hosoi, Takuji*; Kirino, Takashi*; Kagei, Yusuke*; Uenishi, Yusuke*; Chanthaphan, A.*; Yoshigoe, Akitaka; Teraoka, Yuden; Shimura, Takayoshi*
Applied Physics Letters, 99(2), p.021907_1 - 021907_3, 2011/07
Times Cited Count:123 Percentile:95.50(Physics, Applied)Watanabe, Heiji*; Kirino, Takashi*; Uenishi, Yusuke*; Chanthaphan, A.*; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Hosoi, Takuji*; et al.
ECS Transactions, 35(2), p.265 - 274, 2011/05
Times Cited Count:8 Percentile:92.63(Electrochemistry)Watanabe, Heiji*; Kirino, Takashi*; Kagei, Yusuke*; Harries, J.; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Hosoi, Takuji*; et al.
Materials Science Forum, 679-680, p.386 - 389, 2011/03
Times Cited Count:27 Percentile:99.51(Engineering, Multidisciplinary)Watanabe, Heiji*; Hosoi, Takuji*; Kirino, Takashi*; Uenishi, Yusuke*; Chanthaphan, A.*; Ikeguchi, Daisuke*; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; et al.
ECS Transactions, 41(3), p.77 - 90, 2011/00
Times Cited Count:5 Percentile:89.76(Electrochemistry)Watanabe, Heiji*; Kirino, Takashi*; Kagei, Yusuke*; Harries, J.; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Hosoi, Takuji*; et al.
no journal, ,
Channel registibity of SiC-MOSFETs becomes larger with decreasing carrier mobility due to defects in the SiO/SiC interface. Although channel mobility is larger than that of 4H-SiC(0001)Si face in the MOSFET fabricated on the 4H-SiC(000-1)C face, degradation of reliability for an oxide layer is remarkable. Valence band off-set and interface level density of the SiO
/SiC interface are different from the former 4H-SiC(0001)Si face. Physical origins for these characters has not known yet. Thus, in order to make clear the origin of reliability degradation and interface characteristics of (000-1)C face, the energy band structure and chemical bonding states of the SiO
/SiC interface formed by thermal oxidation.
Hosoi, Takuji*; Kirino, Takashi*; Chanthaphan, A.*; Ikeguchi, Daisuke*; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Shimura, Takayoshi*; et al.
no journal, ,
no abstracts in English
Kirino, Takashi*; Kagei, Yusuke*; Okamoto, Gaku*; Harries, J.; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Hosoi, Takuji*; et al.
no journal, ,
In order to study the origin of degradation for interface chracteristics and reliability of SiC(0001)C surfaces, chemical bonding states at SiO/SiC interfaces made on (000
)
and (000
)
surfaces have been analyzed by using a synchrotron radiation XPS method. Si2p
components were extracted from Si2p photoemission peaks. Sub-oxidea components were observed in addition to the SiC substrate and the oxide layer. In the interface of the oxide layer formed on the (000
)
surface, Si
component was small, higher oxidation number components were larger, and total amount od sub-oxides was larger comparing to that of the (000
)
surface. A binding energy for oxide formed on the (000
)
surface was shifted to 0.22 eV higher side comparing to that of the (000
)
surface. It indicates that band off-set of conduction band is small in the SiO
/SiC interface.
Kutsuki, Katsuhiro*; Okamoto, Gaku*; Hideshima, Iori*; Uenishi, Yusuke*; Kirino, Takashi*; Harries, J.; Yoshigoe, Akitaka; Teraoka, Yuden; Hosoi, Takuji*; Shimura, Takayoshi*; et al.
no journal, ,
Direct deposition of ZrO films on Ge substrates and subsequent thermal oxidation results in an equivalent oxide thickness (EOT) of above 2 nm while obtaining good interface quality due to interfacial GeO
formation. In this work, we proposed the use of Ge
N
interlayer formed by high-density plasma nitridation for further EOT scaling because of its high resistance to oxidation and superior thermal stability. The structural modification of ZrO
/Ge
N
/Ge after oxidation was characterized by synchrotron-radiation X-ray photoelectron spectroscopy at BL23SU in SPring-8. Ge 3d core-level spectra revealed that the Ge
N
interlayer was slightly oxidized after thermal oxidation at 823 K, but N 1s spectra remained almost unchanged. This indicates that the Ge
N
interlayer is effective in suppressing interfacial oxidation, thus obtaining an EOT of 1.8 nm.
Kirino, Takashi*; Kagei, Yusuke*; Okamoto, Gaku*; Harries, J.; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Hosoi, Takuji*; et al.
no journal, ,
Device ability of SiC-MOSFET's expected from physical data has not been achieved because channel resistance increases by mobility degradation due to Si0/SiC interface defects. Although high channel mobility is obtained in the MOSFET's made on a 4H-SiC(000-1)c face compared to them on a 4H-SiC(0001)Si face, reliability of an oxide film is preferential in the MOSFET's on a 4H-SiC(000-1)c face. Conduction band off-set of SiO
/SiC interface and energy distribution of the interface level density are known to be different between MOSFET's on a 4H-SiC(000-1)c face and a 4H-SiC(0001)Si face. Physical origins for them are not known yet. In order to make clear the reasons for degradation of interface characteristics and reliability in the MOSFET's made on an SiC(000-1)c face, we evaluated chemical bonding states and energy band structures of SiO
/SiC interfaces formed on an SiC(0001)Si face and an SiC(000-1)c face using synchrotron radiation photoemission spectroscopy.
Kirino, Takashi*; Chanthaphan, A.*; Ikeguchi, Daisuke*; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Hosoi, Takuji*; Shimura, Takayoshi*; et al.
no journal, ,
In order to investigate correlation between a conduction band offset and the interface characteristics of SiO/SiC structure, synchrotron radiation XPS have been conducted for the SiO
/SiC structure formed by sputtering and thermal oxidation. In the SiO
/SiC interface formed by sputtering, higher oxidation number components decreased and the total amount of suboxides was small comparing with thermal oxidation. Furthermore, an SiO
photoemission peak of the sputtering sample was shifted to higher binding energy side by 0.24 eV, and a conduction band offset was smaller comparing with the thermal oxide sample. The SiO
band gap was evaluated from an O1s energy loss spectrum, and the valence band offset was also obtained from a valence band photoemission spectrum. The conduction band offset for the sputtering sample was smaller by 0.35 eV comparing with the thermal oxide sample.
Hosoi, Takuji*; Kirino, Takashi*; Chanthaphan, A.*; Ikeguchi, Daisuke*; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Shimura, Takayoshi*; et al.
no journal, ,
A balence band off-set of SiO/SiC interface, which affects the reliability of SiC-MOS devises, was evaluated by synchrotron radiation photoemission spectroscopy. An SiO
film formed by sputtering deposition showed smaller off-set than that of thermal oxide film. Interface defects, originate in carbon impurities, and balence band off-set of thermal SiO
/SiC interface were decreased by annealing in the high temperature hydrogen gas.
Kirino, Takashi*; Kagei, Yusuke*; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Hosoi, Takuji*; Shimura, Takayoshi*; Watanabe, Heiji*
no journal, ,
Watanabe, Heiji*; Kagei, Yusuke*; Kosono, Kohei*; Kirino, Takashi*; Watanabe, Yu*; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Yoshigoe, Akitaka; Teraoka, Yuden; et al.
no journal, ,
SiC-MOSFET's are expected for normally-off-type high performance power devices. Electrical defects due to residual inpurities such as carbon are in the interface of thermally-oxidized SiC-MOS's so that channel mobility is degraded preferentially. Although upgrade of reliability of a gate insulator is necessary for practical use, insulator degradation mechanisms have not well known yet. We are studying high quality MOS interface made by plasma nitridation techniques, upgrade of reliability and insulation by a stuck structure of a high-k insulator (AlON) layer and an SiO underlayer. Recent research results on those subjects are reported in this talk.
Kirino, Takashi*; Kagei, Yusuke*; Okamoto, Gaku*; Harries, J.; Yoshigoe, Akitaka; Teraoka, Yuden; Mitani, Shuhei*; Nakano, Yuki*; Nakamura, Takashi*; Hosoi, Takuji*; et al.
no journal, ,
It has been reported that hydrogen incorporation into thermally grown SiO/4H-SiC structures not only improves the interface quality, but also degrades the gate oxide reliability depending on SiC surface orientation. In this study, energy band diagrams of thermally grown SiO
/4H-SiC(0001) and SiO
/4H-SiC(000-1) structures with and without high-temperature hydrogen annealing were evaluated by synchrotron radiation X-ray photoelectron spectroscopy. The SiO
band gap and valence band offset at SiO
/SiC interface were extracted from O 1s energy loss spectra and valence band spectra, respectively. The obtained energy band diagrams revealed that conduction band offsets at SiO
/SiC interfaces were decreased after the hydrogen annealing especially for 4H-SiC(000-1) substrates. This is one possible reason for the reliability degradation of 4H-SiC metal-oxide-semiconductor devices by hydrogen incorporation.