黑硅的无掩模反应离子刻蚀法制备及光学性能研究

Fabrication and Optical Property of Black Silicon Prepared by Non-mask Reactive Ion Etching

采用无掩模反应离子刻蚀法制备了黑硅。利用扫描电子显微镜及紫外-可见-近红外分光光度计研究了黑硅的微结构和光学特性。结果表明,黑硅微结构高度为2.0~3.5μm,径向尺寸90~400nm,间距200~610nm。在400~1 000nm光谱范围内黑硅吸收率为94%,是单晶硅的1.5倍;在1 200~1 700nm光谱范围吸收率为55%~60%,是B掺杂单晶硅的20倍。制备的黑硅的光学带隙为0.600 6eV,吸收光谱明显向红外方向偏移。

The black silicon was prepared by non-mask reactive ion etching.Then the microstructure and optical properties were studied by means of scan-electron microscopy and UVVIS-NIR spectrophotometer.The results show that,the height of microstructure is 2.0~3.5μm and the diameter is 90~400nm with a distance of 200~610nm.The absorptance of the black silicon produced by non-mask reactive ion etching remains 94%in the wavelength range of 400~1 000 nm,which is almost 150% of that of polished monocrystalline silicon.And the absorptance is 55%~60%in the wavelength range of 1 200~1 700 nm,which is 20 times of that of B-doped monocrystalline silicon.The optical bandgap of black silicon is 0.600 6eV,indicating a remarkable red-shift of absorption spectrum.