Influence of interfacial defects on the electronic states at GaN p-i-n diode interfaces

ORAL

Abstract

Although silicon-based electronics are used for light-emitting diodes and electric vehicles, their utility in high power applications is limited by a low breakdown voltage. A promising alternative is vertical GaN devices, but these require regrown active regions. Here, we report on the influence of regrowth processing steps on interfacial defects and their electronic signatures. A comparison of GaN p-i-n structures prepared with and without ex-situ ambient exposure and/or chemical etching reveals the highest interfacial near-band edge (NBE) and donor-acceptor pair (DAP) cathodoluminescence (CL) emission from the in-situ structures. Interestingly, elastic recoil detection analysis (ERDA) and Rutherford backscattering spectroscopy reveal the lowest interfacial [H] but the highest fraction of displaced Ga atoms, suggesting efficient incorporation of MgGa. On the other hand, for the ex-situ structures, minimal interfacial [H] is observed, and the highest surface NBE and DAP CL emission is apparent. Finally, for the etched/regrown structures, ERDA reveals the highest interfacial [H], and significant yellow CL emission is observed. We will discuss relationships between interfacial [H], the fraction of displaced Ga atoms, CL emission features, and diode performance.

*ARPA-E AWD0000191

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Presenters

  • GuanJie Cheng

    • Department of Materials Science and Engineering, University of Michigan
    • Materials Science and Engineering, University of Michigan

Authors

  • GuanJie Cheng

    • Department of Materials Science and Engineering, University of Michigan
    • Materials Science and Engineering, University of Michigan

  • Jiaheng He

    • Department of Materials Science and Engineering, University of Michigan
    • Materials Science and Engineering, University of Michigan

  • Alexandra Zimmerman

    • Department of Materials Science and Engineering, University of Michigan
    • Materials Science and Engineering, University of Michigan

  • Davide Del Gaudio

    • Department of Materials Science and Engineering, University of Michigan
    • Materials Science and Engineering, University of Michigan

  • Fabian Naab

    • Michigan Ion Beam Laboratory, University of Michigan

  • Mohsen Nami

    • Department of Electrical Engineering, Yale University

  • Bingjun Li

    • Department of Electrical Engineering, Yale University

  • Jung Han

    • Department of Electrical Engineering, Yale University

  • Rachel Goldman

    • Univ of Michigan - Ann Arbor
    • Physics and Materials Science and Engineering, University of Michigan
    • Department of Materials Science and Engineering, University of Michigan
    • Materials Science and Engineering, University of Michigan
    • Materials Science Engineering, University of Michigan