Tunnel-injected sub-260 nm ultraviolet light emitting diodes

  title={Tunnel-injected sub-260 nm ultraviolet light emitting diodes},
  author={Yuewei Zhang and Sriram Krishnamoorthy and Fatih Akyol and Sanyam Bajaj and A. A. Allerman and Michael W. Moseley and Andrew M. Armstrong and Siddharth Rajan},
  journal={Applied Physics Letters},
We report on tunnel-injected deep ultraviolet light emitting diodes (UV LEDs) configured with a polarization engineered Al0.75Ga0.25 N/In0.2Ga0.8 N tunnel junction structure. Tunnel-injected UV LED structure enables n-type contacts for both bottom and top contact layers. However, achieving Ohmic contact to wide bandgap n-AlGaN layers is challenging and typically requires high temperature contact metal annealing. In this work, we adopted a compositionally graded top contact layer for non-alloyed… 

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