[20p-W323-1~14] CS.5 9.4/16.2 Code-sharing session

[20p-W323-6] Thermal conductivity reduction by neck effect in periodic hole nanostructures

〇Ryoto Yanagisawa¹, Roman Anufriev¹, Jeremie Maire¹, Masahiro Nomura^1,2,3 (1.IIS Univ. of Tokyo, 2.NanoQuine, 3.JST PRESTO)

Keywords:thermal phonon transport,nanosturucture,silicon

Thermal phonon transport in nanostuructures was investigated. Silicon phononic crystals (PnCs) composed of nano beam structure with periodic hole array were fabricated and measured thermal conductivities by thermo-refrectance method. From a particle point of view, phonons have a wide range of mean free path (MFP) and heat is carried by all phonons. We observed neck effect in which long MFP phonons are strongly scattered at the narrowest part in structures, and large hole structures which have small neck showed reduced thermal conductivities even in long period structures which have less holes. This neck size dependence of thermal conductivity will help design of the PnC thermoelectric divices.