Premium
Reduction of reverse‐leakage current in selective‐area‐grown GaN‐based core–shell nanostructure LEDs using AlGaN layers
Author(s) -
Rishinaramangalam Ashwin K.,
Nami Mohsen,
Shima Darryl M.,
Balakrishnan Ganesh,
Brueck Steven R. J.,
Feezell Daniel F.
Publication year - 2017
Publication title -
physica status solidi (a)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.532
H-Index - 104
eISSN - 1862-6319
pISSN - 1862-6300
DOI - 10.1002/pssa.201600776
Subject(s) - materials science , reverse leakage current , light emitting diode , optoelectronics , doping , silicon , nanostructure , diode , impurity , layer (electronics) , current density , nanotechnology , schottky diode , chemistry , physics , organic chemistry , quantum mechanics
We report a simple method to improve the p‐type doping efficiency and eliminate the diode leakage current in selective‐area‐grown GaN‐based core–shell nanostructure LEDs by growing an n‐type AlGaN layer underneath the InGaN/GaN active region. A significant reduction in reverse‐leakage current density is correlated with longer AlGaN layer growth time and higher flow rate of the aluminum precursor. A comparison of the SIMS profiles with and without the underlayer indicates a high concentration of donor‐type impurities (e.g., silicon and oxygen) in the p‐GaN layer in the structure with no AlGaN underlayer. Conversely, LEDs with an AlGaN underlayer exhibit enhanced magnesium incorporation and much lower silicon and oxygen impurity concentrations within the p‐GaN layer. The reverse current density was also reduced by the addition of a p‐type AlGaN electron blocking layer above the active region.