TY - JOUR
T1 - In Situ Transmission Electron Microscopy Observations of Forward Bias Degradation of Vertical Geometry β-Ga2O3Rectifiers
AU - Islam, Zahabul
AU - Haque, Aman
AU - Glavin, Nicholas
AU - Xian, Minghan
AU - Ren, Fan
AU - Polyakov, Alexander Y.
AU - Kochkova, Anastasia
AU - Tadjer, Marko
AU - Pearton, S. J.
N1 - Publisher Copyright:
© 2020 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited.
PY - 2020/1/6
Y1 - 2020/1/6
N2 - The microstructural changes and degradation under forward bias of vertical β-Ga2O3 rectifiers were observed by in-situ transmission electron microscopy. The devices show both a voltage dependence for the onset of visible degradation as well as a time dependence at this threshold voltage, suggesting a defect percolation process is occurring. The degraded rectifiers show a large decrease in forward current and different types of crystal defects are present, including stacking fault tetrahedra, microcracks, Ga-rich droplets and Au inclusions from the top electrode. Continued forward bias stressing is known to lead to macro-cracks oriented along the [010] crystal orientation and eventual delamination of the epitaxial drift layer, but this study is the first to provide insight into the appearance of the smaller defects that precede the large scale mechanical failure of the rectifiers. The initial stages of bias stressing also produce an increase in deep trap states near EC-1.2 eV.
AB - The microstructural changes and degradation under forward bias of vertical β-Ga2O3 rectifiers were observed by in-situ transmission electron microscopy. The devices show both a voltage dependence for the onset of visible degradation as well as a time dependence at this threshold voltage, suggesting a defect percolation process is occurring. The degraded rectifiers show a large decrease in forward current and different types of crystal defects are present, including stacking fault tetrahedra, microcracks, Ga-rich droplets and Au inclusions from the top electrode. Continued forward bias stressing is known to lead to macro-cracks oriented along the [010] crystal orientation and eventual delamination of the epitaxial drift layer, but this study is the first to provide insight into the appearance of the smaller defects that precede the large scale mechanical failure of the rectifiers. The initial stages of bias stressing also produce an increase in deep trap states near EC-1.2 eV.
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U2 - 10.1149/2162-8777/ab981d
DO - 10.1149/2162-8777/ab981d
M3 - Article
AN - SCOPUS:85087108399
SN - 2162-8769
VL - 9
JO - ECS Journal of Solid State Science and Technology
JF - ECS Journal of Solid State Science and Technology
IS - 5
M1 - 055008
ER -