Anthony Davidson, M.Twigg, P.E.Thompson, T. Worchesky
Applied Physics Letters, Vol. 107, Issue 14, Page 1 (2015)
The URL for the article is https://aip.scitation.org/doi/10.1063/1.4932163
Abstract: In this work, we examine the thermal diffusivity of Si/SiGe thin-film superlattice (SL) structures and use these results with previous thermal conductivity results to calculate the heat capacity from 374K to 674 K. The thermal properties of semiconductor layered structures can be altered through the use of SL structures. This alteration occurs through two possible mechanisms: increased phonon scattering due to rough interfaces and phonon zone folding due to boundary conditions of the propagating waves. Examining the heat capacity allows for the observation of phonon zone folding effects while limiting effects due to scattering. Structures studied here consist of SiGe SLs grown at different temperatures and with varying SL spacing allowing the examination of period and crystallinity effects on thermal properties.