【摘要】 利用椭偏反射光谱不但验证了Si-SiO₂界面是一祖糙面,而且在恰当的模拟形貌下,把这界面粗糙层等效为若干子层,用有效介质理论处理。分别得到各自的介电特性。通过多相椭偏光反射光谱的理论计算值ψ_cal,△_cal与实验值ψ_exp,△_exp的比较,把粗糙的高度H及相关长度L确定,把不同条件下制备的样品的粗糙度和它们的电气性能相对比,发现两者之间的趋势十分一致。同时发现,在界面上Si的介电常数具有轻度的各向异性。更多还原

【Abstract】 The roughness at the Si-SiO2 interface has been determined by the ellipsometric spectroscopy. Several geometric forms have been used to simulate the surface irregularities. The dielectric properties of the rough layer are modelled in the effective-medium approximation by dividing the rough layer into a number of sub-layers with equal thickness. The asperity height H （normal to surface） and the correlation length L （along the surface） can be defined by best fit of the theoretically calculated multiphase reflective ellipsometric parameters ψ_cal, △_cal to the measured ellipsometric parameters ψ_exp, △_exp. It is found that the trend of the electric properties of the sample is consistent with the variance of its roughness. It is also found that the dielectric function of Si has some anisotropic properties at the interface.更多还原