[18p-P15-1~11] 22.1 Joint Session M "Phonon Engineering"

[18p-P15-5] Annealing time dependence of thermal conductivity of poly-Si PnC nanostructures

〇Ryoto Yanagisawa¹, Naohito Tsujii², Oliver Paul³, Takao Mori², Masahiro Nomura^1,4,5 (1.IIS Univ. of Tokyo, 2.NIMS, 3.IMTEK, 4.NanoQuine, 5.JST PRESTO)

Keywords:Silicon, Thermoelectrics, Phononic Crystal

We measured thermal conductivity of poly-Si membrane as a function of annealing time. We found thermal conductivity decreases as annealing time become shorter, which indicates short anneal sample has smaller polycrystalline grain size and shows strong phonon scattering. Finally, we achieved 80 % lower thermal conductivity by combining this grain size engineering and phononic crystal nanostructures toward thermoelectric application.