论文标题
光声技术对硅纳米结构的热性能研究
Thermal properties study of silicon nanostructures by photoacoustic techniques
论文作者
论文摘要
提出了带有压电检测的光声方法，以同时评估热物理特性。该方法是基于额外的散热器沉降，以重新分布沉积在样品表面上的热通量。首先，该方法在多孔硅具有明确定义的形态和良好的特性上进行了测试。然后，通过数值模拟恢复实验数据，研究了硅纳米线阵列的热容量和导热率。观察到样品的厚度和孔隙率增加，热容量的降低和样品的有效导热率。这种行为可能是由于结构异质性的增加而引起的。特别是，这可能与在厚层的蚀刻过程中出现的较大的疾病（破碎的纳米线和较大孔隙度的密度增加）有关。
The photoacoustic method with piezoelectric detection for the simultaneous evaluation of the thermophysical properties is proposed. The approach is based on the settling of an additional heat sink for redistribution of heat fluxes deposited on the sample surface. Firstly, the approach was tested on the porous silicon with well-defined morphology and well-studied properties. Then, heat capacity and thermal conductivity of silicon nanowires arrays have been investigated by recovering the experimental data through numerical simulations. The decrease of heat capacity and effective thermal conductivity of the samples upon increasing thickness and porosity of the sample is observed. Such behavior could be caused by the increase of the structure heterogeneity. In particular, this can be related to larger disorder (increased density of broken nanowires and larger porosity) that appears during the etching process of the thick layers.
