Enhanced infrared normal spectral emissivity of microstructured silicon at 200 to 400 °C

The infrared normal spectral emissivity of microstructured silicon prepared by femtosecond laser was measured for the middle infrared waveband at temperature range 200 to 400°C. Compared to that of flat silicon, emissivity was enhanced over the entire wavelength range. For a sample with different spike height, the max emissivity at a temperature of 300°C emissivity nearly reaches to 0.99 . Although the average emissivity is not very higher, it can be used stably at more wide temperature ranges. These results show the potential for microstructured silicon to be used as a flat blackbody source or silicon-based devices.