摘要
本文采用等离子体增强化学气相沉积(PECVD)技术,在普通玻璃上制备了本征和掺磷的氢化微晶硅(μc-Si∶H)薄膜。利用Raman散射谱,计算了表征其薄膜微结构的晶化率(Xc)和平均晶粒尺寸(d)。结果表明随着磷烷(PH3)浓度的增加,其Xc和d均呈现了先增加后减小的相似趋势;利用测得的透射谱和反射谱,并利用Tauc公式拟合了μc-Si∶H薄膜的光学带隙(Egopt)。研究表明,μc-Si∶H薄膜的Egopt与Xc具有相反的变化趋势。该结果可利用Kronig-Penney模型和表征函数F(x)作出合理解释。
The intrinsic and p-doped hydrogenated silicon micro-crystalline films (μc-Si : H) were grown by plasma enhanced chemical vapor deposition(PECVD) on glass substrates. The influence of various film growth conditions on film quality was studied. Its microstructures were characterized with crystalline volume fraction(Xc) and its average grain size (d) were evaluated with Raman spectroscopy. The results show that the partial pressures ratio of phosphine (PH3) and silane (SiH4) strongly affects the microstructures and optical properties of the films. For instance, as the ratio increases, both its Xc and of d first increase and then decrease, but its optical energy gap (Egopt) first decreases and then increases. The Egopt of the p-doped μc-Si: H films was derived by means of the transmission and reflectance spectra, and a datafitting with Tauc formula. We found that the Egopt of the p-doped μc-Si: H films is bigger than that of the intrinsic amorphous silicon films. The dependence of the optical energy gap on the ratio can be well explained with Kronig-Penney Model and characterization function F(x).
出处
《真空科学与技术学报》
EI
CAS
CSCD
北大核心
2008年第4期365-369,共5页
Chinese Journal of Vacuum Science and Technology
基金
国家"973"子课题(No.2006CB202601)