Dependence of Optical Absorption in Silicon Nanostructures on Size of Silicon Nanoparticles  

作　　者：丁文革 苑静 孟令海 武树杰 于威 傅广生 

机构地区：[1]College of Physics Science and Technology,Hebei University

出　　处：《Communications in Theoretical Physics》2011年第4期688-692,共5页理论物理通讯（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant No.60940020;the Natural Foundation of Hebei Province under Grant No.E2008000619

摘　　要：The amorphous silicon nanoparticles （Si NPs） embedded in silicon nitride （SiNx） films prepared by helicon wave plasma-enhanced chemical vapor deposition （HWP-CVD） technique are studied. From Raman scattering investigation, we determine that the deposited film has the structure of silicon nanocrystals embedded in silicon nitride （nc-Si/SiNx） thin film at a certain hydrogen dilution amount. The analysis of optical absorption spectra implies that the Si NPs is affected by quantum size effects and has the nature of an indirect-band-gap semiconductor. Further, considering the effects of the mean Si NP size and their dispersion on oscillator strength, and quantum-confinement, we obtain an analytical expression for the spectral absorbance of ensemble samples. Gaussian as well as lognormal size-distributions of the Si NPs are considered for optical absorption coefficient calculations. The influence of the particle size-distribution on the optical absorption spectra was systematically studied. We present the fitting of the optical absorption experimental data with our model and discuss the results.

关 键 词：optical absorption silicon nanoparticles quantum size effects oscillator strength silicon nitride film 

分 类 号：O484.41[理学—固体物理]