Micro-reflectance (μ-R) spectroscopy is a powerful technique for investigating the micro-scaled surfaces and interfaces, such as semiconductors, metals, etc. We discuss and compare the μ-R spectroscopy on specular (Si wafer) and scattering (MoS2 flake) surfaces using various objectives with different NA. μ-R is calculated by the ratio of sample to reference spectra, it follows the sequence of NA on scattering surface, which is proven by larger NA showing better performance for scattered irradiance due to its wider collection angle. Micro-reflectance difference (μ-RD) of each wavelength is further calculated, and it’s 30 times larger on scattering MoS2 flake surface than specular Si wafer surface.
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