کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6534898 49299 2016 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Light-induced reflectivity transients in black-Si nanoneedles
ترجمه فارسی عنوان
پرتوهای بازتابندگی نور ناشی از نانوذرات سیاه سی
کلمات کلیدی
سیلیکون سیاه، نانو سوزن، انعکاس دیفرانسیل، بیضه سنجی طیف سنجی،
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
چکیده انگلیسی
The change in reflectivity of black-Si (b-Si) upon optical excitation was measured by the pump-probe technique using picosecond laser pulses at 532 (pump) and 1064 nm (probe) wavelengths. The specular reflection from the random pattern of plasma-etched b-Si nano-needles was dominated by the photo-excited free-carrier contribution to the reflectivity. The kinetics of the reflectivity were found to be consistent with surface structural and chemical analysis, performed by scanning and transmission electron microscopy, and spectroscopic ellipsometry. The surface recombination velocity on the b-Si needles was estimated to be ~102cm/s. Metalization of b-Si led to much faster recombination and alteration of reflectivity. The reflectivity spectra of random b-Si surfaces with different needle lengths was modeled by a multi-step refractive index profile in the Drude formalism. The dip in the reflectivity spectra and the sign reversal in the differential reflectivity signal at certain b-Si needle sizes is explained by the model.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solar Energy Materials and Solar Cells - Volume 144, January 2016, Pages 221-227
نویسندگان
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