氦压对类金刚石薄膜结构和光学性质的影响  

Effect of He pressure on microstructure and optical properties of diamond-like carbon films

作　　者：丁旭丽[1] 李清山[1,2] 徐言东[1] 于业梅[1] 李新坤[1] 

机构地区：[1]曲阜师范大学物理工程学院,山东曲阜273165 [2]鲁东大学,山东烟台264025

出　　处：《物理实验》2009年第4期11-15,共5页Physics Experimentation

摘　　要：使用脉冲激光沉积技术在不同氦压下制备了系列无氢类金刚石薄膜,测量了样品的Raman光谱、光吸收光谱和光致发光光谱,采用原子力显微镜测试了薄膜的表面形貌,研究了薄膜的微结构和光学性质与制备条件的依赖关系.结果表明,该薄膜是由sp2和sp3杂化碳原子组成的非晶碳膜.薄膜的光学带隙在1.45～1.78 eV.薄膜的发光在可见光区呈宽带结构,氦压能够对类金刚石薄膜的结构和光学性质产生较大影响.当氦压从0.05 Pa升高至15 Pa时,sp2团簇变大,带尾态增多,从而导致薄膜的发光增强,光学带隙变窄,发光峰位红移.AFM形貌表明随着氦压的升高,薄膜的表面由致密光滑变得粗糙,并且许多大小不均匀的球状颗粒出现在薄膜表面.Hydrogen-free diamond-like carbon films are prepared by pulsed laser deposition at different He pressures. The films are amorphous carbon films involving sp^2 and sp^3 hybridized carbon. The photoluminescence is a broad band in the visible region. Optical band gap is in the range of 1.45 -1.78 eV. When the He pressure is increased from 0.05 Pa to 15 Pa, the sp^2 clusters become larger and the ordering of carbon atoms is improved, which result in a decrease of the optical band gap and a Spectral red shift of the PL peaks accompanied by a significant increase in intensity. The surface morphology changes from smooth to roughness with the increase of He pressure and many asymmetric particles appear on the surface.

关 键 词：类金刚石薄膜 脉冲激光沉积 氦压 

分 类 号：O484[理学—固体物理] TN304.18[理学—物理]