The impacts of sidewall passivation via atomic layer deposition on GaN-based flip-chip blue mini-LEDs. (15th September 2022)

• Record Type: Journal Article
• Authors: Lai, Shouqiang; Lin, Wansheng; Chen, Jinlan; Lu, Tingwei; Liu, Shibiao; Lin, Yi; Lu, Yijun; Lin, Yue; Chen, Zhong; Kuo, Hao-Chung; Guo, Weijie; Wu, Tingzhu
• Is Part Of: Journal of physics. Volume 55:Number 37(2022)
• Publication Date: 2022-09-15
• Subjects: sidewall passivation -- atomic layer deposition -- mini-LEDs; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/ac7b51
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: In order to investigate the photoelectric characteristics of 80 × 120 µ m 2 mini-light-emitting-diodes (mini-LEDs) with sidewall passivation by atomic layer deposition (ALD), this paper uses the techniques of spectrometer-based spectroradiometer and microscopic hyperspectral imaging ( µ -HSI). The temperature-dependent electroluminescence is measured using a spectrometer-based spectroradiometer. By analyzing the rising parts of external quantum efficiency at room temperature with a two-level model, the difference of physical mechanisms between mini-LEDs with ALD and without ALD are determined. In addition, the thermal quenching indicates that the ALD sidewall passivation can enhance the temperature stability of the mini-LEDs. The ALD sidewall passivation also enhances the light extraction efficiency according to the theoretical calculation of transmittance. Moreover, the µ -HSI technique is used to evaluate different local areas of mini-LEDs. The obtained results reveal the optimization on lateral distribution of current density within the chip after sidewall passivation.