[TuP3D] D. Photonic devices and related technologies

[TuP3D-01] Cryogenic Behavior of AlGaInP Red Micro-LEDs: Extraction of Sidewall Surface Recombination Velocity via ABC Model

〇Cheng-En Wu¹, Ming-June Wu¹, Natchanon Prechatavanich¹, Chee Keong Yee¹, Zhi-An LIN¹, Zih-Wei Cyue¹, Wing-Kit Choi¹, Chao-Hsin Wu¹ (1. National Taiwan Univ. (Taiwan))

We study the cryogenic efficiency behavior of AlGaInP/GaAs red micro-LEDs and quantify sidewall-related nonradiative loss using size scaling with ABC-model analysis. EQE–J was measured at 300 K and 80 K for mesa sizes from 13×20 µm² to 52×80 µm². The data were fitted with an ABC recombination model including a leakage/overflow contribution to extract temperature-dependent recombination parameters. By comparing devices with different perimeter-to-area ratios, we separate bulk and sidewall Shockley–Read–Hall recombination and extract an effective sidewall surface recombination velocity. Results indicate reduced sidewall recombination under cryogenic operation, improving small-pixel performance where sidewall effects dominate. Radiative and Auger-related contributions remain largely size-independent, so scaling trends are mainly governed by sidewall loss and leakage. These insights provide a practical diagnostic for process optimization and highlight sidewall passivation and leakage suppression as key routes to higher-efficiency AlGaInP red micro-LED pixels for low-temperature display and photonic applications.