【摘要】 多孔硅优良的热学性能使其成为MEMS领域新兴的热绝缘材料。文中采用一种简便且无损的多孔硅热导率测量技术——显微拉曼光谱技术对电化学腐蚀法制备的不同孔隙率和厚度的多孔硅试样热导率进行了测量,结果表明在多孔硅的拉曼谱峰位置与其温度间存在线性对应关系。在所有样品中,厚度为110μm空隙率为65%的多孔硅显示出最好的绝热性能,其热导率为0.624W/mK。且随多孔硅孔隙率和厚度的减小,其热导率有迅速增加的趋势(厚度和孔隙率为9μm和40%时,其热导率升至25.32W/mK)。更多还原

【Abstract】 Porous silicon (PS) was used as a new thermal insulating material in MEMS during last five years due to its low thermal conductivity (TC). A simple and nondestructive method, micro-Raman technique, was applied to study the TC of PS samples with different porosity and thickness prepared by electrochemical method in this paper. It is found that there is a linear relationship between the Raman peak position and temperature of porous silicon. Within all the samples, the 110 μm thick PS with a porosity of 65% presents the lowest TC value which is 0.624 W/mK. Then, the TC of porous silicon increases rapidly with decreasing porosity and thichness (when the thickness and porosity decrease to 9 μm and 40%, the TC increases to 25.32 W/mK).更多还原