Published online by Cambridge University Press: 10 February 2011
Photonic bandgap structures have received much attention as optical and infrared filters with controllable narrow-band absorbance. There is a need, however, for the same kind of control of the thermal emittance of surfaces for applications ranging from control of radiative heat transfer to gas absorption spectroscopy. We report on the fabrication of photonic bandgap structures on silicon surfaces using standard lithographic techniques. Substrate resistivity varied from n− to n+ and in some cases background surface emissivity was suppressed with a high reflectivity coating such as aluminum. We have measured the infrared reflectance and emittance of these patterned surfaces. Peak absorption wavelength and spectral purity (linewidth) correlate with photonic bandgap feature size and spacing as well as surface conductivity. We demonstrate band emission with a sharp short wavelength cut-off from these structures when heated.