InGaN Nanopixel Arrays on Single Crystal GaN Substrate

PubDate: Jun 2025

Teams:1Centre Energie, Matériaux et Télécommunications, Institut national de la recherche scientifique(INRS-EMT), Varennes, Québec J3X 1P7, Canada.
2Institute of High-Pressure Physics, Polish Academy of Sciences,Sokolowska 29/37, 01-142 Warsaw, Poland
3Department of Electrical and Electronic Engineering, Bangladesh University of Engineering and Technology (BUET), West Palashi, Dhaka 1205, Bangladesh.
4Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109, United States

Writers:Nirmal Anand, Sadat Tahmeed Azad, Christy Giji Jenson, Dipon Kumar Ghosh, Md Zunaid Baten, Pei-Cheng Ku, Grzegorz Muziol, Sharif Sadaf

PDF:InGaN Nanopixel Arrays on Single Crystal GaN Substrate

Abstract

Indium gallium nitride (InGaN) quantum well (QW) micro- and nanoscale light-emitting diodes (LEDs) are promising for next-generation ultrafast optical interconnects and augmented/virtual reality displays. However, scaling to nanoscale dimensions presents significant challenges, including enhanced nonradiative surface recombination, defect and/or dislocation-related emission degradation and nanoscale pixel contact formation. In this work, we demonstrate strain-engineered nanoscale blue LED pixels fabricated via top-down nanostructuring of an all-InGaN quantum well/barrier heterostructure grown by plasma-assisted molecular beam epitaxy (PAMBE) on significantly low dislocation-density single-crystal GaN substrates. Sidewall passivation using atomic layer deposition (ALD) of Al2O3 enables excellent diode behavior, including a high rectification ratio and extremely low reverse leakage. Monte Carlo analyses suggest almost 100% yield of completely dislocation-free active regions for 450 nm nanopixels. Electroluminescence measurements show bright blue emission with a peak external quantum efficiency (EQE) of 0.46%. Poisson Schrodinger simulations reveal partial strain relaxation in the QW, effectively mitigating the quantum confined Stark effect (QCSE). Additionally, finite-difference time-domain (FDTD) simulations confirm that the nanoscale geometry enhances light extraction efficiency by over 40% compared to planar designs, independent of substrate materials. These results establish a scalable pathway for dislocation free, high-brightness InGaN microLED arrays suitable for advanced display and photonic systems.