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 kW•cm^-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.

延长一维（1D）半导体纳米线（NW）仍然是一个很大的挑战，对于将宏观设备小型化和/或集成为厘米级长度，这可能是有吸引力的平台。本文中，我们通过图形化外延剥离（GELO）蓝宝石上的外延膜，报道了创新的单晶III型氮化物NW的制备方法，其空前的长度超过2 cm，长宽比超过6000。提议的GELO技术涉及各向同性干法蚀刻和选择性电化学（EC）蚀刻。EC蚀刻的反应动力学研究表明，包括两步过程，据我们所知，这是首先揭示并通过实验证实的。厘米长的独立式NW，具有均匀设计的GaN，p-GaN /（InGaN / GaN）_6的结构成功获得了量子阱/ n-GaN（简称InGaN / GaN QWs）和AlGaN / AlN / GaN异质结构，并具有优异的形态均匀性和鲁棒性。由于释放的本征应变，释放的InGaN / GaN QW-NW的光学性能得到了很好的优化。通过单个InGaN / GaN QW-NW的连续波激发意外地观察到了随机激射行为，其低阈值为232 kW•cm ^-2。这项工作代表了一种低成本，经济的方法来生产结构可工程化的超长III氮化物NW，这将促进光电子纳米器件的开发和集成。