Optimized performances in InGaN/GaN quantum-well membrane based vertical optoelectronics by the Piezo-phototronic effect. (November 2021)

• Record Type: Journal Article
• Authors: Lin, Yutian; Chen, Xin; Dong, Jianqi; He, Chenguang; Zhao, Wei; Chen, Zhitao; Zhang, Kang; Wang, Xingfu
• Is Part Of: Nano energy. Volume 89(2021)Part A
• Publication Date: 2021-11
• Subjects: Piezo-phototronic effect -- InGaN/GaN QWs membrane -- LED -- PD -- Polarization characteristics; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2021.106454
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: In this work, by conducting selective electrochemical (EC) etching of the sapphire based nitrides epitaxial film, freestanding InGaN/GaN quantum-wells (QWs) membrane was firstly and specifically prepared. InGaN/GaN QWs based device with vertical geometry were then fabricated using the membranes, which can work either as a light-emitting diode (LED) or as a photodetector (PD). The emission intensity and polarization characteristics of vertical devices are optimized by introducing the Piezo-phototronic effect under external straining. Under a tensile strain of 2.04%, the relative electroluminescence (EL) intensity of the LED is increased by 183%, which is ascribed to the enhancement of carriers recombination arisen from the external-strain-induced Piezo-phototronic effect. And the polarization ratio of the emission light is increased or decreased by 135% and 56% under the tensile or compressive strain of 2.04%. For the PD working mode, the polarization ratio of photoresponse current is increased by 107% under the condition of 2.04% tensile strain, while it is reduced by 81% under compressive strain. The modulated polarization characteristics in the vertical devices were attributed to the adjustment in anisotropic optoelectronic properties of InGaN/GaN QWs. This work provides a novel method to fabricate vertical nitride optoelectronics and also presents a unique strategy to their optoelectronic performances. Graphical Abstract: In this work, freestanding InGaN/ GaN QW membrane was prepared to fabricate vertical geometry devices, which can work as a light emitting diode (LED) or a photodetector (PD). The Piezo-phototronic effect was then introduced to modulate optoelectronic characteristics of the vertical devices. ga1 Highlights: Freestanding InGaN/ GaN QWs membrane was used to fabricate vertical devices that can work as an LED or a photodetector (PD). The Piezo-phototronic effect was introduced to improve emission efficiency of the fabricated vertical LED. The polarized emission or photoresponse properties of the fabricated devices are modulated by the Piezo-phototronic effect.