Uniform SiGe/Si quantum well nanorod and nanodot arrays fabricated using nanosphere lithography
1 Institute of Materials Science and Engineering, National Central University, No. 300, Jhongda Rd., Jhongli 32001, Taoyuan, Taiwan
2 Department of Chemical and Materials Engineering, National Central University, Jhongli 32001, Taiwan
Nanoscale Research Letters 2013, 8:349 doi:10.1186/1556-276X-8-349Published: 8 August 2013
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.