PHONON TRANSPORT IN NANOSTRUCTURES WITH APPLICATION TO ULTRA-THIN SILICON-ON-INSULATOR (SOI) TRANSISTORS NSF NIRT Grant 0103082

The fundamentals of phonon transport in nanostructures are not well understood at present. The continuum assumption fails in the nanoscale regime where either mean free path or wavelength of the phonons becomes comparable with the characteristic dimension of the nanostructures. Ballistic phonon transport in silicon films (phonon-boundary scattering) has been investigated through the large measured reductions in the lateral thermal conductivity compared to the bulk value [1], shown in Fig. 1. However, the phonon boundary scattering is not the only sub-continuum effect that occurs in nanoscales. The scaling of transistors has reduced the channel length and subsequently the size of the intense phonon-electron interactions in the active region of the transistor. The small size of the phonon source compare