TY - JOUR
T1 - Driving force of oxygen-ion migration across high-k/SiO2 interface
AU - Kunugi, Ryota
AU - Nakagawa, Nobuhiro
AU - Watanabe, Takanobu
N1 - Funding Information:
The authors are grateful to Professor K. Kita, Professor A. Toriumi, and Mr. J. Fei (The University of Tokyo); Professor A. Ogura (Meiji University); and Professor S. Satoh (University of Hyogo) for their helpful discussions. This work was supported by CREST, JST, and a Grant-in-Aid for Scientific Research (B) (15H03979) from the Ministry of Education, Culture, Sports, Science and Technology of Japan.
Publisher Copyright:
© 2017 The Japan Society of Applied Physics.
PY - 2017/3
Y1 - 2017/3
N2 - We clarified the mechanism of oxygen (O-)-ion migration at a high-k/SiO2 interface, which is a possible origin of the flat-band voltage shift in metal/high-k gate stacks. The oxygen density difference accommodation model was reproduced by a molecular dynamics simulation of an Al2O3/SiO2 structure, in which O- ions migrate from the higher oxygen density side to the lower one. We determined that the driving force of the O--ion migration is the short-range repulsion between ionic cores. The repulsive force is greater in materials with a higher oxygen density, pushing O- ions to the lower oxygen density side.
AB - We clarified the mechanism of oxygen (O-)-ion migration at a high-k/SiO2 interface, which is a possible origin of the flat-band voltage shift in metal/high-k gate stacks. The oxygen density difference accommodation model was reproduced by a molecular dynamics simulation of an Al2O3/SiO2 structure, in which O- ions migrate from the higher oxygen density side to the lower one. We determined that the driving force of the O--ion migration is the short-range repulsion between ionic cores. The repulsive force is greater in materials with a higher oxygen density, pushing O- ions to the lower oxygen density side.
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U2 - 10.7567/APEX.10.031501
DO - 10.7567/APEX.10.031501
M3 - Article
AN - SCOPUS:85014125063
SN - 1882-0778
VL - 10
JO - Applied Physics Express
JF - Applied Physics Express
IS - 3
M1 - 031501
ER -