Defect‐enabled electrical current leakage in ultraviolet light‐emitting diodes

Authors:
Publisher website
Google Scholar
Abstract
Electrical current leakage paths in AlGaN‐based ultraviolet (UV) light‐emitting diodes (LEDs) are identified using conductive atomic force microscopy. Open‐core threading dislocations are found to conduct current through insulating Al0.7Ga0.3N layers. A defect‐sensitive H3PO4 etch reveals these open‐core threading dislocations as 1–2 µm wide hexagonal etch pits visible with optical microscopy. Additionally, closed‐core threading dislocations are decorated with smaller and more numerous nanometer‐scale pits, which are quantifiable by atomic‐force microscopy. The performances of UV‐LEDs fabricated on similar Si‐doped Al0.7Ga0.3N templates are found to have a strong correlation to the density of these electrically conductive open‐core dislocations, while the total threading dislocation densities of the UV‐LEDs remain relatively unchanged.

This publication has 22 references indexed in Scilit: