Transconductance enhancement of Si nanowire transistors by oxide-induced strain

Evaluation of controlled strain in silicon nanowire by UV Raman spectroscopy

“…However, the stresses obtained by water-immersion Raman spectroscopy are very small compared with previously reported MD simulation results. 11,12) We consider that the cause of stress differences is the relatively large width of the Si NWs compared with the oxide film thickness. As a result, it is considered that the effect of the oxide film is small, and that the stresses (σ xx and σ yy ) decrease accordingly.…”

“…Seike and coworkers have indicated that controlling the oxidation-dependent strain in Si NWs is important for the improvement in mobility. 11,12) In addition, Zushi and coworkers have shown that a decrease in κ is caused by the disorder strain induced in SiO 2 =Si NWs by molecular dynamics (MD) simulation. [13][14][15] From these findings, to realize Si NW devices with high electric and thermoelectric performance characteristics, further improvements through the optimization of strain in the nanowires covered with an oxide film, as well as size, impurity, and crystallinity, are necessary to achieve a higher mobility and a lower κ.…”

“…By Raman spectroscopy using a UV excitation source, some researchers including our group have evaluated the physical properties of Si NWs. 11,12,[20][21][22] However, in previous studies, Si NWs covered with oxide films were merely distinguished through the presence of strains, and an actual measurement of stress has not been performed yet by Raman spectroscopy. In addition, the effect of oxide films on the strain in Si NWs has not yet been investigated in detail.…”