Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA.
Nano Lett. 2013 Feb 13;13(2):550-4. doi: 10.1021/nl304060g. Epub 2013 Jan 28.
The thermal conductivity of suspended few-layer hexagonal boron nitride (h-BN) was measured using a microbridge device with built-in resistance thermometers. Based on the measured thermal resistance values of 11-12 atomic layer h-BN samples with suspended lengths ranging between 3 and 7.5 μm, the room-temperature thermal conductivity of a 11-layer sample was found to be about 360 W m(-1) K(-1), approaching the basal plane value reported for bulk h-BN. The presence of a polymer residue layer on the sample surface was found to decrease the thermal conductivity of a 5-layer h-BN sample to be about 250 W m(-1) K(-1) at 300 K. Thermal conductivities for both the 5-layer and the 11-layer samples are suppressed at low temperatures, suggesting increasing scattering of low frequency phonons in thin h-BN samples by polymer residue.
采用内置电阻温度计的微桥器件测量了悬浮少层六方氮化硼（h-BN）的热导率。基于 11-12 原子层 h-BN 样品在 3-7.5μm 之间悬浮长度的测量热阻值，发现 11 层样品在室温下的热导率约为 360 W m(-1) K(-1)，接近块状 h-BN 报道的基面值。在样品表面发现存在聚合物残留层，会将 5 层 h-BN 样品的热导率在 300K 时降低到约 250 W m(-1) K(-1)。这两种样品的热导率在低温下都受到抑制，这表明聚合物残留会增加薄 h-BN 样品中低频声子的散射。
