tailieunhanh - Báo cáo hóa học: " Effect of thermal treatment on the growth, structure and luminescence of nitride-passivated silicon nanoclusters"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Effect of thermal treatment on the growth, structure and luminescence of nitride-passivated silicon nanoclusters | Wilson et al. Nanoscale Research Letters 2011 6 168 http content 6 1 168 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Effect of thermal treatment on the growth structure and luminescence of nitride-passivated silicon nanoclusters 1 11 2 1 Patrick RJ Wilson Tyler Roschuk Kayne Dunn Elise N Normand Evgueni Chelomentsev Othman HY Zalloum1 Jacek Wojcik1 Peter Mascher1 Abstract Silicon nanoclusters Si-ncs embedded in silicon nitride films have been studied to determine the effects that deposition and processing parameters have on their growth luminescent properties and electronic structure. Luminescence was observed from Si-ncs formed in silicon-rich silicon nitride films with a broad range of compositions and grown using three different types of chemical vapour deposition systems. Photoluminescence PL experiments revealed broad tunable emissions with peaks ranging from the near-infrared across the full visible spectrum. The emission energy was highly dependent on the film composition and changed only slightly with annealing temperature and time which primarily affected the emission intensity. The PL spectra from films annealed for duration of times ranging from 2 s to 2 h at 600 and 800 C indicated a fast initial formation and growth of nanoclusters in the first few seconds of annealing followed by a slow but steady growth as annealing time was further increased. X-ray absorption near edge structure at the Si K- and L3 2-edges exhibited compositiondependent phase separation and structural re-ordering of the Si-ncs and silicon nitride host matrix under different post-deposition annealing conditions and generally supported the trends observed in the PL spectra. Introduction Quantum confinement effects have been found to improve the efficiency of radiative recombination in silicon 1 . In accordance with Heisenberg s uncertainty principle the spatial confinement of the charge carriers induces a spread in their .