Chinese Physics B ( IF 1.7 ) Pub Date : 2020-11-14 , DOI: 10.1088/1674-1056/abc0d4 Ji-Bin Fan 1 , Shan-Ya Ling 1 , Hong-Xia Liu 2 , Li Duan 1 , Yan Zhang 1 , Ting-Ting Guo 1 , Xing Wei 1 , Qing He 1
Effects of initial surface termination on electrical characteristics of La2O3/Al2O3 nanolaminates deposited by atomic layer deposition are studied by conductive atomic force microscopy working in contact mode and standard electrical characterization methods. It is found that, compared with La2O3/Al2O3 nanolaminates with LaO x as termination, lower interface trap density, less current leakage spots, and higher breakdown voltage are obtained in the La2O3/Al2O3 nanolaminates with AlO x as termination after annealing. A clear promotion of interface silicate layer is observed for La2O3/Al2O3 nanolaminates with AlO x as termination compared with LaO x as termination under the same annealing condition. In addition, the current conduction mechanism in La2O3/Al2O3 nanolaminates is considered as the Poole–Frenkel conduction. All results indicate that the AlO x is a more appropriate termination to deposit La2O3/Al2O3 nanolaminates on Si substrate, which is useful for the high-κ process development.