Utilizing silicon nanoporous pillar array (Si- NPA )as substrates, two nanocomposite systems, SiC nanoparticle/Si-NPA(nc-SiC/Si-NPA) and SiC nanowire/Si-NPA(nw-SiC/Si-NPA) were prepared by a chemical vapor deposition method. The surface morphologies, chemical compositions and room-temperature humidity-sensing properties of the two systems were characterized. It was disclosed that the capacitance response of both nc-SiC/SiNPA and nw-SiC/Si- NPA were highly sensitive to vapor. With the relative humidity ( RH ) changing from 11％ to 95％ and at a testing frequency of 100 Hz,a capacitance increment of 750％ for nc-SiC/Si-NPA and 1050％ for nwSiC/Si-NPA was achieved,and the corresponding response/recovery times were determined to be 100/150 s and 10/10 s,respectively. The high humidity-sensitivity of the two systems was attributed to the enlargement of the sensing areas caused by the presentation of large quantities of nc-SiC and nw-SiC, while the short response/recovery times were due to the formation of effective vapor transportation paths provided by the array structure of Si-NPA.%以硅纳米孔阵列(Si-NPA)为衬底,采用化学气相沉积法分别制备了SiC纳米颗粒/Si-NPA(nc-SiC/Si-NPA)和SiC纳米线/Si-NPA(nw-Si/Si-NPA)复合体系,并对其表面成分和形貌、室温湿敏性能进行了表征.实验结果表明,nc-SiC/Si-NPA和nw-SiC/Si-NPA均对水蒸气表现出灵敏的电容响应.当环境相对湿度从%增加到95%,在100Hz的测试频率下nc-SiC/Si-NPA的电容增加了750%,而nw-SiC/Si-NPA的电容增加了1050%.通过升湿和降湿动态过程,测得nc-SiC/Si-NPA的响应和恢复时间均为10 s,nw-SiC/Si-NPA的响应和恢复时间分别为100s和150 s.分析表明,nc-SiC/Si-NPA、nw-SiC/Si-NPA对湿度的高度敏感性主要源于nc-SiC、nw-SiC所引起感应面积的巨大增加,而其较短的响应和恢复时间则归因于阵列结构为水蒸气提供了有效的传输通道.
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