Confinement effect of optical phonons in Si–Ge alloy nanocrystals

Raman Measurements of Optical Phonon Scattering in Sub-Micron Si_(1-x)Ge_x Films

“…As carbon transitions from graphite to amorphous carbon, the Raman spectrum evolves from a single narrow peak to multiple peaks and eventually to a spectrum that is very similar to the vibrational density of states. A similar result is found for nano-crystalline [103,112,113] and amorphous tetrahedral semiconductors [114].…”

Twinning defects in spherical GeSi alloy nanocrystals

“…In the Raman spectra of the sample annealed at 1100 1C for 90 min, three peaks with peak-positions at 293, 408 and 483 cm À1 are strong, corresponding to the well-known optic phonon peaks of GeSi alloy [8]. The average element composition of nc-Ge 1Àx Si x was estimated to be x$0.40 and $0.46 according to the positions of the Raman and X-RD peaks, respectively.…”

“…Therefore, ncGeSi might be applied more flexibly in optoelectronics. Unfortunately, only a few investigations have focused on the preparation and microstructure of nc-GeSi [7][8][9][10]. Moreover, the microstructural defects inside nc-GeSi have never been studied in detail.…”

Optimization ofμc-Si1−xGex:H Single-Junction Solar Cells with Enhanced Spectral Response and Improved Film Quality

“…The substantial increase in a-Ge-Ge and a-Si-Ge peaks indicated a fraction of Ge was incorporated into amorphous phase and thus suppressed the formation of crystalline phase. Moreover, the weak peak at approximately 247 cm −1 was observed in c-Si 1−x Ge x :H alloys, which was originated from the resonant mode [23,24] and overlapped with amorphous background of Ge-Ge mode. Another weak peak at 430 cm −1 was assigned to a localized Si-Ge phonon mode.…”