氢化碳化硅薄膜作为一种宽带隙的半导体材料,具有优越的物理特性,其在光电子器件上的潜在应用引起了人们的兴趣。利用等离子增强化学气相沉积(PECVD)系统制备了一系列氢化碳化硅薄膜,通过改变反应前驱物及流量比调节薄膜的室温光致发光性质。实验发现在一定范围内随着流量比R(CH4/SiH4)的提高,氢化碳化硅薄膜的光致发光峰位蓝移且发光强度增强;同时反应前驱物中的氢会极大影响氢化碳化硅薄膜的发光强度。通过椭偏仪(Ellipsometer)测量了薄膜的光学常数,发现薄膜沉积速率随着流量比R的增加而降低;傅里叶红外光谱仪(FTIR)测试表明Si-C有序度随着流量比的增加而增大。同时研究了三维纳米线结构对多态碳化硅薄膜发光性质的影响。光致发光测试结果表明三维纳米线结构可以有效提高薄膜的光致发光强度。
Hydrogenated silicon-carbon thin film(SixC(1-x):H),as a wide-band semiconductor material,has very promising applications in opto-electronic areas.Series of SixC(1-x):H films were prepared by using plasma-enhanced chemical vapor deposition system(PECVD).By increasing the flux ratio of the gas source(R = CH4/SiH4),it is found that the peak position of the PL blue-shifts and PL intensity photoluminescence to the decrease in the size of Si nanoparticles(nc-Si) embedded in the matrix and the increase in the numbers of nc-Si.The precursor H2 has influence on the PL intensity as the presence of H2 can boost the nucleation and growth of the nc-Si.The optical properties of the films were analyzed by Ellipsometry and FTIR measurement.Importantly,3D nanowire structure of the film greatly enhanced the PL intensity,which provides another way to improve the PL efficiency.These results are fundamentals for study on Si based opto-electronics.