Rana Abu Ul Hassan Sarwar, Kim Hyun-Seok
Division of Electronics and Electrical Engineering, Dongguk University-Seoul, Seoul 04620, Korea.
Materials (Basel). 2017 Dec 27;11(1):37. doi: 10.3390/ma11010037.
Previous studies on Ga-doped ZnO nanorods (GZRs) have failed to address the change in GZR morphology with increased doping concentration. The morphology-change affects the GZR surface-to-volume ratio and the real essence of doping is not exploited for heterostructure optoelectronic characteristics. We present NH₄OH treatment to provide an optimum morphological trade-off to n-GZR/p-Si heterostructure characteristics. The GZRs were grown via one of the most eminent and facile hydrothermal method with an increase in Ga concentration from 1% to 5%. The supplementary OH ion concentration was effectively controlled by the addition of an optimum amount of NH₄OH to synchronize GZR aspect and surface-to-volume ratio. Hence, the probed results show only the effects of Ga-doping, rather than the changed morphology, on the optoelectronic characteristics of n-GZR/p-Si heterostructures. The doped nanostructures were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, photoluminescence, Hall-effect measurement, and Keithley 2410 measurement systems. GZRs had identical morphology and dimensions with a typical wurtzite phase. As the GZR carrier concentration increased, the PL response showed a blue shift because of Burstein-Moss effect. Also, the heterostructure current levels increased linearly with doping concentration. We believe that the presented GZRs with optimized morphology have great potential for field-effect transistors, light-emitting diodes, ultraviolet sensors, and laser diodes.
先前对镓掺杂氧化锌纳米棒（GZRs）的研究未能解决随着掺杂浓度增加 GZR 形态的变化问题。形态变化会影响 GZR 的表面体积比，并且未充分利用掺杂的真正本质来研究异质结构的光电特性。我们提出用氢氧化铵处理，以在 n-GZR/p-Si 异质结构特性方面实现最佳的形态权衡。GZRs 通过最著名且简便的水热法生长，镓浓度从 1%增加到 5%。通过添加适量的氢氧化铵有效控制额外的氢氧根离子浓度，以同步 GZR 的长径比和表面体积比。因此，所探究的结果表明，在 n-GZR/p-Si 异质结构的光电特性中，仅存在镓掺杂的影响，而非形态变化的影响。通过扫描电子显微镜、能量色散 X 射线光谱、X 射线衍射、光致发光、霍尔效应测量和 Keithley 2410 测量系统对掺杂的纳米结构进行了表征。GZRs 具有相同的形态和尺寸，呈典型的纤锌矿相。随着 GZR 载流子浓度的增加，由于伯斯坦 - 莫斯效应，光致发光响应出现蓝移。此外，异质结构的电流水平随掺杂浓度线性增加。我们认为，所呈现的具有优化形态的 GZRs 在场效应晶体管、发光二极管、紫外传感器和激光二极管方面具有巨大潜力。
