新型高K栅介质ZrO_2薄膜材料的制备及表征

Preparation and characterization of ZrO_2 thin films as novel high-K gate dielectrics

采用超高真空电子束蒸发法制备了新型高K栅介质—非晶ZrO2薄膜。X射线光电子能谱(XPS)中Zr3d5/2和Zr3d3/2对应的结合能分别为182.1eV和184.3eV,Zr元素的主要存在形式为Zr4+,说明薄膜由完全氧化的ZrO2组成,并且纵向分布均一。扩展电阻法(SRP)显示ZrO2薄膜的电阻率在108Ω·cm以上,通过高分辨率透射电镜(HR-XTEM)可以观察ZrO2/Si界面陡直,没有界面反应产物,证明600℃快速退火后ZrO2薄膜是非晶结构。原子力显微镜(AFM)表征了薄膜的表面粗糙度,所有样品表面都很平整,其中600℃快速退火样品(RTA)的RMS为0.480nm。

Amorphous ZrO2 thin films as novel high-K gate dielectrics were deposited at roomtemperature by Ultra-high Vacuum Electron Beam Evaporation XPS spectra show that the binding energies of Zr3d5/2 and Zr3d3/2 are 182.1eV and 194.3eV, respectively, Zr is mainly in its Zr4+statewhich means that the thin film is mainly composed of ZrO2, and the distribution of chemical com-ponents across the thin films is uniform. Spreading Resistance Profile reveals the resistivity of the thinfilms is more than 108Ω·cm, and the interface between zirconia thin films and Si substrate is abruptand clear without interfacial reaction products, which is also verified by High Resolution cross sec-tional Transmission Electron Microscopy (HR-XTEM). X-ray Diffraction and HR-XTEM results show that the 600oC-annealed sample is amorphous. Atomic Force Microscope was used to charac-terize the surface roughness, and all the samples have smooth surfaces, among which the 600oC rapidthermal annealed sample is smooth with RMS roughness 0.480nm.