Abstract
To examine influence of microstructure made on an emitter surface, spectrally selective property of the emitter was investigated through numerical simulation and experiment. In the simulation, thermal radiation from solid surface is dealt as hemispherical emission from point sources and Maxwell's equations are solved using CIP method. It was demonstrated that around the wavelength corresponding to the normal mode of cavity resonance, emissivity of the emitter could be amplified, while at wavelengths corresponding to the higher modes, emissivity didn't increase. The results indicated possibility of spectral control by making use of the microstructure on the emitter surface. Furthermore, to verify the validity of simulation results obtained, rectangular microcavities (0.5×0.5×0.5μm^3) were made periodically on nickel emitter surface (2.0×2.0mm^2) through photolithography and fast atom beam etching techniques. Heating of sample was conducted in a vacuum chamber to avoid oxidation and spectral emissivity was measured in the near infrared region. The measured spectral property showed cutoff effect at 1.0μm and amplification of emissive power below that.
