基片温度对电子束蒸发沉积碳化硼薄膜性能的影响

Effect of Substrate Temperature on Properties of Boron Carbide Thin Films Deposited by Electron Beam Evaporation

在不同基片温度下,采用电子束蒸发法在Si(100)衬底上制备了碳化硼薄膜,研究了基片温度对薄膜性能的影响。采用X射线光电子能谱仪(XPS)分析了薄膜成分,薄膜的表面形貌用原子力显微镜(AFM)进行表征,采用台阶仪和椭偏测厚仪测量了薄膜厚度和折射率。结果表明基片温度对薄膜成分影响不大;随着基片温度的升高,薄膜表面粗糙度逐渐增大,均方根粗糙度由0.394 nm增至0.504 nm;而沉积速率先增大后减小,在300℃时达到最大值7.47 nm/min;其折射率由2.06渐增至2.41,表明薄膜致密性逐渐提高。

Boron carbide thin films were deposited on Si(100) substrates by electron beam evaporation at different substrate temperatures.The effect of substrate temperature on properties of boron carbide films,such as chemical composition and surface roughness,was investigated by using X-ray photoelectron spectroscopy(XPS),atomic force microscope(AFM),surface profiler(Alpha-step) and ellipsometer.XPS results show that the substrate temperature has no obvious influence on the chemical composition of the films.AFM measurements show that the surface roughness increases as the substrate temperature increases,and the root-mean-square(RMS) roughness increases from 0.394 to 0.504 nm.The deposition rate first increased and then decreased as substrate temperature increases,and it reaches a maximum value 7.47 nm/min when the substrate temperature is 300 ℃.With the substrate temperature increasing,the refractive index of boron carbide films increases gradually from 2.06 to 2.41,which indicates that boron carbide films become higher density gradually.