We demonstrate a 440nm emitting flip-chip GaN LED utilizing photoelectrochemical (PEC) etching for substrate removal. The device was flip-chipbonded to a thermally conductive silicon carbide substrate, which allowed for CW operation at current densities up to 200A/cm2 with minimal thermal droop. The PEC etch provided a damage-free method of removing substrates and could allow for substrate reuse. The epitaxially defined etch also exposed a highly doped n-contact layer, which contributed to the low operating voltage of 3.74V at 400A/cm2 and a peak wall plug efficiency (WPE) of 7%.
Bibliographical noteKAUST Repository Item: Exported on 2022-05-31
Acknowledgements: The authors would like to thank Kenji Fujito of Mitsubishi Chemical Corporation for providing high-quality free-standing GaN substrates. This work was funded in part by the King Abdulaziz City for Science and Technology (KACST) Technology Innovations Center (TIC) program and the KACST-KAUST-UCSB Solid State Lighting Program, and the Solid State Lighting and Energy Electronics Center (SSLEEC) at the University of California, Santa Barbara (UCSB). Part of this work was carried out at the UCSB nanofabrication facility, part of the NSF NNIN network (ECS-0335765), as well as the UCSB MRL, which is supported by the NSF MRSEC program (DMR-1121053).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.