Scopul nostru este sprijinirea şi promovarea cercetării ştiinţifice şi facilitarea comunicării între cercetătorii români din întreaga lume.
Autori: D. Moraru, H. Kato, S. Horiguchi, Y. Ishikawa, H. Ikeda and M. Tabe
Editorial: Extended Abstracts of the 2005 International Conference on Solid State Devices and Materials, p.178-179, 2005.
Study on coherent nature of electrons in tunneling through SiO2 is important in developing novel Si devices such as resonant tunneling devices and optical devices. In this work, we attack this problem again by adopting new structures based on the wafer bonding technique, i.e., Si(111)/SiO2/Si(111) structures, in which the two facing Si layers are intentionally misoriented with various twist angles. It is expected that, if the transverse momentum is conserved after tunneling through the SiO2 layer, the potential discontinuity “seen” by the tunneling electrons at the SiO2/collector-Si interface and consequently the reflectivity at this interface will depend on the twist angle. Change in reflectivity of electron wave leads to the change in the amplitude of Fowler-Nordheim current oscillations (FNCOs). In fact, we have found a systematic change in the amplitude of FNCOs as a function of the twist angle between the Si layers, indicating the conservation of transverse momentum.
(SSDM Young Researcher Award – 2006)
Cuvinte cheie: Fowler-Nordheim current oscillations, ultrathin silicon oxide, electron tunneling
Autori: *D. Moraru, H. Kato, S. Horiguchi, Y. Ishikawa, H. Ikeda, and M. Tabe
Editorial: Japanese Journal of Applied Physics, 45, p.L316-L318, 2006.
The dependence of Fowler–Nordheim current oscillations (FNCOs) on the twist angle between the facing Si layers in Si(111)/SiO2/Si(111) bonded structures is investigated. The observed systematic variation in oscillation amplitude with twist angle can be ascribed to transverse momentum conservation upon Fowler–Nordheim tunneling through thin SiO2. A calculation result, taking into account the twist-induced decrease in potential discontinuity and consequently in the reflection coefficient at the SiO2/twisted Si interface, provides the theoretical basis for the experimental results.
Cuvinte cheie: transverse momentum conservation, Fowler–Nordheim tunneling, Fowler–Nordheim current oscillations, Si/SiO2/Si structures