Optical reflection spectra with wavelengths from 0.3 to 2 μm for the as-grown and etched samples. The spectra were measured at an incident angle of 5°. The inset also shows the variation in reflectance at 1.55 μm as a function of etching times.
Chang et al. Nanoscale Research Letters 2013 8:349 doi:10.1186/1556-276X-8-349