一种基于多孔硅微腔光学特性的气体传感器的研究

当有机物分子吸附到多孔硅表面时,由于有机物分子在多孔硅的孔内的毛细冷凝作用,将引起多孔硅层有效折射率的变化,从而导致多孔硅微腔反射谱吸收峰峰位的变化.本文主要利用Bruggeman介电常数近似理论与传输矩阵的方法,建立了多孔硅微腔的传感模型.使用多孔硅微腔的反射谱实验装置对多孔硅微腔进行了传感实验,结果证明多孔硅微腔传感元件可以实现对有机物蒸汽的检测,且分辨率较高,响应时间和恢复时间短,可重复性好.

Study on a gas sensor basing on the optical character of porous silicon microcavities

When the porous silicon is exposed to vapor of several organic species, the average refractive index of the microcavity is increased, ascribed to capillary condensation of the vapor in the silicon pore, result in different resonant peak shift values in the reflectivity spectra. In this work, we set up sensing model of PSMs by applying the Bruggeman effective medium approximation theory and the method of transference matrix. Using experimental setup to measure the reflectivity spectrum of SPMs, experimental results prove that it is a feasible optical sensor for organic species detecting. Resolution of the PSMs sensor is high, response time and resume time is short and well repetition.