Zhou Zicheng, Sohn Honglae
Department of Chemistry, Chosun University, Gwangju 61452, Korea.
School of Chemistry and Chemical Engineering, Cangzhou Normal University, Cangzhou 061001, China.
Sensors (Basel). 2020 May 10;20(9):2722. doi: 10.3390/s20092722.
In this study, an innovative rugate filter configuration porous silicon (PSi) with enhanced photoluminescence intensity was fabricated. The fabricated PSi exhibited dual optical properties with both sharp optical reflectivity and sharp photoluminescence (PL), and it was developed for use in organic vapor sensing. When the wavelength of the resonance peak from the rugate PSi filters is engineered to overlap with the emission band of the PL from the PSi quantum dots, the PL intensity is amplified, thus reducing the full width at half maximum (FWHM) of the PL band from 154 nm to 22 nm. The rugate PSi filters samples were fabricated by electrochemical etching of highly doped n-type silicon under illumination. The etching solution consisted of a 1:1 volume mixture of 48% hydrofluoric acid and absolute ethanol and photoluminescent rugate PSi filter was fabricated by etching while using a periodic sinusoidal wave current with 10 cycles. The obtained samples were characterized by scanning electron microscopy (SEM), and both reflection redshift and PL quenching were measured under exposure to organic vapors. The reflection redshift and PL quenching were both affected by the vapor pressure and dipole moment of the organic species.
在本研究中，制备了一种具有增强光致发光强度的创新型波纹滤光器结构多孔硅（PSi）。所制备的PSi展现出兼具尖锐光学反射率和尖锐光致发光（PL）的双重光学特性，并且它被开发用于有机蒸汽传感。当将来自波纹PSi滤光器的共振峰波长设计为与来自PSi量子点的PL发射带重叠时，PL强度会增强，从而将PL带的半高宽（FWHM）从154nm减小到22nm。波纹PSi滤光器样品是通过在光照下对高掺杂n型硅进行电化学蚀刻制备的。蚀刻溶液由48%氢氟酸和无水乙醇按1:1体积比混合而成，并且通过在使用具有10个周期的周期性正弦波电流的同时进行蚀刻来制备光致发光波纹PSi滤光器。所获得的样品通过扫描电子显微镜（SEM）进行表征，并且在暴露于有机蒸汽的情况下测量反射红移和PL猝灭。反射红移和PL猝灭均受有机物种的蒸汽压和偶极矩影响。
