Raman Spectra and Temperature-Dependent Raman Scattering of Silicon Nanowires

The room-temperature Raman spectra of silicon nanowires with diameters ranging from 15 to 30 nm are studied. The results indicate that with the decrease of the diameter of the silicon nanowires, the first-order Raman peak positions red shift, and the line widths broaden. The temperature-dependent Raman spectra of silicon nanowires are studied by taking the effects of phonon confinement, lattice stress, and anharmonic potential into account. The enhanced anharmonic effect in nanowires has been discovered.