室温下Cu/3C-SiC(111)界面形成的研究  

Initial Stage of Cu/3C-SiC(111) Interface formation at Room Temperature

作　　者：刘衍芳[1] 李亮[1] 刘金锋[1] 刘忠良[1] 徐彭寿[1] 徐法强[1] 潘海斌[1] 

机构地区：[1]中国科学技术大学国家同步辐射实验室,合肥230029

出　　处：《真空科学与技术学报》2009年第1期42-45,共4页Chinese Journal of Vacuum Science and Technology

基　　金：国家自然科学基金项目(No.50572100)

摘　　要：用同步辐射光电子能谱(SRPES)和X射线光电子能谱(XPS)的方法研究了室温下Cu/3C-SiC(111)界面的形成。在超高真空下,Cu慢慢沉积到2ML。Cu2p3/2用XPS测得,结合能从沉积0.08ML时的933.1eV移动到沉积2ML的932.8eV,Si2p用同步辐射光测得,峰位从未沉积时的43.55eV移动到沉积2ML的43.87eV,峰形状未发生变化,表明Cu与衬底之间没有发生化学反应,薄膜的生长开始为二维生长,超过0.1ML时变为三维生长,SiC的表面有表面态存在,当沉积少量的Cu时,表面态消失。随着Cu的沉积价带(VB)发生弯曲,肖特基势垒高度增加,在沉积2MLCu时肖特基势垒变为1.2eV。The copper and 3C-SiC（111） junctions were fabricated at room temperature with copper films,deposited by vacuum evaporation, on substrate of 3C-SiC（ 111 ） films, grown by molecular beam epitaxy （MBE）. The interfacial microstmctures and stoichiometries in the initial stage of the Cu/3CSiC interface formation were characterized with synchrotron radiation photoelectron spectroscopy （SRPES） and X-ray photoelectron spectroscopy （XPS）. The results show that the Cu coverage significantly affects the various factors, including the surface states of the SiC, the Cu film growth modes, Schottky barrier heights, the binding energy and the band bending. For instance, as the coverage of Cu increases from 0.08ML（monolayer） to 2.0ML,the XPS peak position of Cu2P3/2 shifts from 933.1 eV to 932.8 eV.And the peak of the kinetic energy of Si2p core level in the SRPES spectra moves from 43.55 eV to 43.87 eV, when at Cu coverage changes from 0.0 ML to 2.0ML. The fairly stable, unchanged peak shapes show no distinctive chemical reaction of Cu and the substrate. Moreover, we found that the 2D growth mode of Cu films changes into 3D growth mode at a Cu critical coverage of 0. 1 ML. Besides, all the surface states of SiC vanish instantly after the Cu deposition starts. Interesting finding is that as Cu films grow, the valence band （VB） bends, and Schottky barrier height rises up, 2eV at a Cu coverage of 2.0ML.

关 键 词：CU 3C—SiC界面 肖特基势垒 同步辐射光电子能谱 

分 类 号：O472.1[理学—半导体物理] O484.1[理学—物理]