电化学制备薄黑硅抗反射膜

采用计算机控制电流密度按指数规律衰减对单晶硅进行电化学腐蚀，得到了折射率随薄膜厚度连续均匀变化的抗反射膜，即黑硅样品. 这种在制取上快速、经济和工艺非常简单的样品，不仅在较宽波段范围内反射率小于5%，且整个薄膜厚度不足1μm. 利用传输矩阵方法对黑硅样品的反射谱进行模拟，得到了理论与实验符合较好的结果. 关键词： 多孔硅 折射率 抗反射膜 黑硅

"Black silicon" antireflection thin film prepared by electrochemical etching

Solar cells and optical detection devices are often covered with antireflective surfaces to enhance their performance. An economical, fast, and easily operational electrochemical etching technique has been developed to realize a continuous uniform variation in the refractive index of porous silicon layer as a function of the etching depth. By using this technique a black silicon sample was fabricated, which has a reflectance below 5% over a broad band and a thickness below 1μm. The depression mechanism of the optical reflectance is analyzed by simulating the structure with the transfer matrix method. The simulated results give a good agreement with the experimental measurements.