Dysprosium oxide (Dy2O3) layer effect on the interface possessions of Au/n-GaN Schottky diode as an interlayer and its chemical and microstructural features

Abstract

The work reveals the design of Au/dysprosium oxide (Dy2O3)/n-GaN metal/insulator/semiconductor (MIS)-type structures with a dysprosium oxide interlayer and investigates its microstructural and chemical states using XRD, TEM and XPS approaches. The outcomes confirm that the Dy2O3 film exists on the n-GaN. The electrical properties of the MIS structure are probed by I–V and C–V procedures. A superior rectifying type with a small leakage current was acquired for the MIS structure rather than the Au/n-GaN Schottky diode (SD). Results showed that the MIS structure has a better barrier height (Φb) (0.91 eV) than the SD (0.82 eV), representing that the Dy2O3 layer modifies the Φb. Using Cheung's, Norde and ΨSP-V plots, the Φb of the SD and MIS structure are derived and the values are nearly similar, representing that the approaches applied here are valid. The predicted NSS of the MIS structure is two orders smaller than the SD, implying that the Dy2O3 interlayer substantially lowers the NSS. The Poole-Frenkel emission is the foremost current transport at a lower bias, though Schottky emission (SE) is ruled as the current transport at a higher bias of the SD. Nevertheless, the SE is prevailing in the current transport in the MIS structure. Consequences endorse that the Dy2O3 layer can be suitable for building of MIS/MOS devices.