Surface termination effects on the electrical characteristics of La₂O₃/Al₂O₃ nanolaminates deposited by atomic layer deposition*

Abstract

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.

Assessing high-energy x-ray and proton irradiation effects on electrical properties of P-GaN and N-GaN thin films

“…[15] However, a number of studies of irradiation effects on P-GaN films, which are the most crucial structural components in enhancement mode heterojunction high electron mobility transistors HEMTs and PIN diodes, is limited. [16] Low-energy protons irradiate enhancement mode GaN HEMTs with a P-GaN layer. Before using devices in radiation environments, it is also essential to consider the displacement and ionizing effects.…”