Centimeter-long III-Nitride nanowires and continuous-wave pumped lasing enabled by graphically epitaxial lift-off. (December 2020)

• Record Type: Journal Article
• Authors: Dong, Jianqi; Wang, Baoyu; Zou, Xianshao; Zhao, Wei; He, Chenguang; He, Longfei; Wang, Qiao; Chen, Zhitao; Li, Shuti; Zhang, Kang; Wang, Xingfu
• Is Part Of: Nano energy. Volume 78(2020)
• Publication Date: 2020-12
• Subjects: III-Nitride -- Ultra-long nanowire -- Graphically epitaxial lift-off -- Reaction kinetics -- Random laser; 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.2020.105404
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: It remains a big challenge to elongate one-dimensional (1D) semiconductor nanowires (NWs), which can be attractive platforms for miniaturizing and/or integrating macroscopic devices, into centimeter-scale length. Herein, we report the innovative preparation of single-crystalline III-nitride NWs, with unprecedented length above 2 cm and the aspect ratio above 6000, by graphically epitaxial lifting-off (GELO) the epitaxial films on sapphire. The proposed GELO technology involves isotropic dry etching and selectively electrochemical (EC) etching. Reaction kinetics study of the EC etching indicate that two-steps processes are included, which is, to our best knowledge, firstly revealed and experimentally confirmed. Centimeter-long freestanding NWs, with predesigned structure of homogeneous GaN, p-GaN/(InGaN/GaN)6 quantum-wells/n-GaN (simply InGaN/GaN QWs) and AlGaN/AlN/GaN heterostructure, are successfully obtained and exhibit superior morphological uniformity and robust flexibility. Optical properties of the released InGaN/GaN QW-NWs were well optimized owing to the relieved intrinsic strain. Random lasing behavior was unexpectedly observed by continuous-wave excitation of the individual InGaN/GaN QW-NW, with a low threshold of 232 kWcm -2 . This work represents a low-cost and economic approach to yield structure-engineerable super-long III-nitride NWs, which would promote the development and integration of optoelectronic nanodevices. Graphical abstract: Image 1 Highlights: Centimeter-long III-nitride NWs with engineerable structure are prepared by the graphically epitaxial lift-off method. Reaction kinetics study of EC etching indicate that two-steps processes are included, which is experimentally confirmed. Continuous-wave pumped random lasing of the individual InGaN/GaN QW-NW was observed with a low threshold of 232 kWcm -2 .