脉冲腐蚀法制备的多孔硅对乙醇气体的响应

Response of Porous Silicon Prepared by Pulsed Electrochemical Etching Method to Ethanol Gas

采用电化学脉冲腐蚀法,在P型单晶硅片上制备了多孔硅(Porous Silicon,PS).以制备的多孔硅为传感元件,利用电感耦合器件(CCD)记录了乙醇蒸汽的反射干涉图.反射光谱经IGOR软件进行傅里叶变换后,得到多孔硅的光学厚度值,并以此为依据探讨多孔硅对乙醇蒸汽的传感特性.实验结果表明,当PS膜暴露于乙醇蒸汽中时,反射谱吸收峰位发生红移,相应的光学厚度也发生红移;当乙醇气体体积分数大于500×10-6时。PS的光学厚度急剧增大.

Porous silicon （PS） is prepared by the pulsed electrochemical etching method on p-type single crystal silicon water. Interferometric reflectance spectra of the prepared samples are recorded using a charge-coupled device （CCD） spectrometer, where the PS is used as a sensing element. In order to discuss ethanol vapor sensing property on the PS, the reflectance spectra of PS are transformed to the values of optical thickness by Fourier transformation with the IGOR software. The experimental results show that the PS exhibits a red-shift in the photonic feature as well as the corresponding optical thickness upon exposure to saturated ethanol vapor. The optical thickness of the PS increases sharply when the concentration of saturated ethanol vapor is greater than 500 ×10^-6.