Observation of comet-shaped defect as killer defect in halide vapor phase epitaxial (001) <i>β</i>-Ga<sub>2</sub>O<sub>3</sub> and its impact on Schottky barrier diodes
Sayleap Sdoeung, Kohei Sasaki, Katsumi Kawasaki, Jun Hirabayashi, Akito Kuramata, Makoto Kasu
Abstract
Abstract We observed killer defects that served as reverse leakage current paths for halide vapor phase epitaxial (001) β -Ga 2 O 3 Schottky barrier diodes, which resulted in a leakage current of −0.46 μ A at reverse bias of −100 V. Synchrotron X-ray topography revealed comet-shaped contrasts extending along [010] which are induced from the strain field surrounding the defects. They consisted of perfect (100)-cracks and horizontal-oriented (001) cracks. The cross-sectional scanning transmission electron microscopy observation showed (100)-cracks on the surface and dislocations along [100] beneath the surface. This defect was speculated to be generated from damage during the chemical-mechanical polishing.