Institute of Materials Science and Engineering, National Central University, No, 300, Jhongda Rd,, Jhongli 32001, Taoyuan, Taiwan.
Nanoscale Res Lett. 2013 Aug 8;8(1):349. doi: 10.1186/1556-276X-8-349.
This study fabricates the optically active uniform SiGe/Si multiple quantum well (MQW) nanorod and nanodot arrays from the Si0.4Ge0.6/Si MQWs using nanosphere lithography (NSL) combined with the reactive ion etching (RIE) process. Compared to the as-grown sample, we observe an obvious blueshift in photoluminescence (PL) spectra for the SiGe/Si MQW nanorod and nanodot arrays, which can be attributed to the transition of PL emission from the upper multiple quantum dot-like SiGe layers to the lower MQWs. A possible mechanism associated with carrier localization is also proposed for the PL enhancement. In addition, the SiGe/Si MQW nanorod arrays are shown to exhibit excellent antireflective characteristics over a wide wavelength range. These results indicate that SiGe/Si MQW nanorod arrays fabricated using NSL combined with RIE would be potentially useful as an optoelectronic material operating in the telecommunication range.
本研究通过纳米球光刻（NSL）结合反应离子刻蚀（RIE）工艺，从 Si0.4Ge0.6/Si 多量子阱（MQW）制备出光学活性均匀的 SiGe/Si 多量子阱纳米棒和纳米点阵列。与未生长的样品相比，我们观察到 SiGe/Si MQW 纳米棒和纳米点阵列的光致发光（PL）光谱明显蓝移，这可以归因于 PL 发射从上层多量子点状 SiGe 层到下层 MQW 的跃迁。还提出了一种与载流子局域化相关的可能机制，以解释 PL 增强。此外，SiGe/Si MQW 纳米棒阵列在宽波长范围内表现出优异的抗反射特性。这些结果表明，使用 NSL 结合 RIE 制备的 SiGe/Si MQW 纳米棒阵列有望作为在电信波段工作的光电材料得到应用。
