Sidewall Interface Nitrogen Treatment for Improving GaN-Based Micron-Scale Light-Emitting Diode Efficiency
Year: 2024
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Defects in the sidewall interfaces are critical to light-emitting efficiency of micro-light emitting diodes (μLEDs) for display applications. The efficiency decreases sharply when the LED chip size is smaller than 10 × 10 μm 2 because the sidewall defect-induced nonradiative recombination process prevails. In this work, we demonstrate the efficiency improvement of GaN-based μLEDs with sizes as small as 4 × 4 μm 2 . Using N 2 plasmon treatment at 250 °C to repair sidewall damage, the light output power of an LED with a mesa size of 4 × 4 μm 2 is improved by 97.29% compared to the reference device without treatment at an injection current density of 25 A/cm 2 . Additionally, compared to a reference device with a mesa area of 100 × 100 μm 2, the optical output power density of the 4 × 4 μm 2 device shows only a 27.11% drop. To understand the effect of nitrogen plasmon treatment on the interfaces, we conducted EDX (energy-dispersive X-ray spectroscopy) and TRPL (time-resolved photoluminescence) analysis on the sidewalls of p-type GaN and the quantum well active region. We concluded that incorporating nitrogen atoms to repair the dangling bonds and, thus, a more balanced Ga/N ratio helps reduce defects and thus improve sidewall radiative efficiency.
Source: ACS Applied Electronic Materials
Authors: Szu-An Chen, Xiang Li, Kuan-Heng Lin, Yi-Hong Chen, Jian-Jang Huang
Institutions: National Taiwan University, AU Optronics (Taiwan)
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Award: G2341024696
OpenAlex ID: W4404142358