Authors: Guozhi Wen Xiangbin Zeng Xianghu Li
Publish Date: 2016/05/11
Volume: 45, Issue: 8, Pages: 4432-4440
Abstract
Silicon quantum dots QDs embedded in nonstoichiometric hydrogenated silicon carbide SiCH thin films have been successfully synthesized by plasmaenhanced chemical vapor deposition and postannealing The chemical composition analyses have been carried out by xray photoelectron spectroscopy XPS The bonding configurations have been deduced from Fourier transform infrared absorption measurements FTIR The evolution of microstructure with temperature has been characterized by glancing incident xray diffraction XRD and Raman diffraction spectroscopy XPS and FTIR show that it is in Sirich feature and there are a few hydrogenated silicon clusters in the asgrown sample XRD and Raman diffraction spectroscopy show that it is in amorphous for the asgrown sample while crystalline silicon QDs have been synthesized in the 900°C annealed sample Silicon atoms precipitation from the SiC matrix or silicon phase transition from amorphous SiC is enhanced with annealing temperature increase The average sizes of silicon QDs are about 51 nm and 56 nm the number densities are as high as 17 × 1012 cm−2 and 32 × 1012 cm−2 and the crystalline volume fractions are about 583 and 613 for the 900°C and 1050°C annealed samples respectively These structural properties analyses provide an understanding about the synthesis of silicon QDs upon thermal annealing for applications in next generation optoelectronic and photovoltaic devices
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