在超高真空条件下,通过脉冲激光技术沉积La_2O_3/LaAlO_3/Si多层膜结构,原位条件下利用同步辐射光电子能谱研究了LaAlO_3作为势垒层的La_2O_3与Si的界面电子结构。实验结果显示,LaAlO_3中Al的2p峰在沉积和退火前后没有变化;衬底硅的芯能级峰在沉积LaAlO_3时没有变化,但在沉积La_2O_3薄膜和退火过程中,硅峰变弱;O的1S芯能级的峰由多种不用的氧化物薄膜层和反应物中的氧杂化而成。结果表明:LaAlO_3从沉积到退火当中,不参与任何反应,Si与LaAlO_3界面相当稳定;在体系中,阻挡层LaAlO_3起到阻挡硅扩散的作用,进一步表明La_2O_3与硅的界面不太稳定。 La_2O_3 / LaAlO_3 / Si multilayers were deposited by pulsed laser deposition under ultra-high vacuum conditions. The interfacial electron structure of La_2O_3 with Si as the barrier layer was studied by using synchrotron radiation photoelectron spectroscopy in situ. The experimental results show that the 2p peak of Al in LaAlO_3 does not change before and after deposition and annealing. The core peak of substrate Si does not change when LaAlO_3 is deposited. However, the peak of Si becomes weaker during the deposition of La_2O_3 thin film and annealing. 1S core level of the peak by a variety of unused oxide film layer and reactants in the oxygen from the hybrid. The results show that LaAlO_3 does not participate in any reaction from deposition to annealing, and the interface between La and LaAlO_3 is quite stable. In the system, LaAlO_3 acts as a barrier to silicon diffusion and further shows that the interface between La_2O_3 and Si is not stable.