Electrical characterization of ZnO ceramics by scanning tunneling spectroscopy and beam-induced current in the scanning tunneling microscope

Abstract

A correlative study of the electrically active grain boundary structure of ZnO polycrystals has been carried out using a scanning electron microscope/scanning tunneling microscope ͑SEM/STM͒ combined instrument. Current imaging tunneling spectroscopy ͑CITS͒ measurements reveal reduced surface band gaps, as compared with grain interiors, at the charged boundaries imaged by SEM-based remote electron beam induced current ͑REBIC͒. ZnO grain boundaries were also imaged in the STM-REBIC mode with a resolution of up to 20 nm. The contrast differences observed in the SEM-REBIC and STM-REBIC images are discussed in terms of the different experimental conditions used in both techniques.

Reformation of La0.7Sr0.3MnO3 properties by using ZnO in La0.7Sr0.3MnO3-ZnO heterostructures grown on (001) oriented Si

“…11 The d I /d V vs. V of ZnO ceramics measured using spatially resolved tunneling spectroscopy shows different widths of the zero conductivity. 36,37 Similar differential conductivity spectra are also observed in the ZnO films grown on (001) oriented InP 38 and (111) oriented Au. 39 Zheng et al observed the donor peaks in the d I /d V vs. V of ZnO single crystals using STM.…”