Polycrystalline defects-origin of leakage current-in halide vapor phase epitaxial (001) β-Ga_2O_3 Schottky barrier diodes identified via ultrahigh sensitive emission microscopy and synchrotron X-ray topography

摘要

Identification of the killer defects is crucial for the development of beta-Ga2O3 Schottky barrier diodes as power electronic devices. We observed the emission patterns that are exhibited by the high reverse leakage current SBDs via ultrahigh-sensitivity emission microscopy, thereby locating a polycrystalline defect on the surface via atomic force microscopy. A single polycrystalline defect resulted in a leakage current of ca. 20 mu A. The synchrotron X-ray topographic analysis of the samples showed butterfly-shaped contrast patterns due to the strain field around the polycrystalline defects. We further observed that a polycrystalline defect is formed over a porous particle.