Thermal model for the bolometric response of YBaCuO films on polycrystalline YSZ at 10.6 mu m wavelength

Economical bolometers, using YBaCuO thin films sputtered on polycrystalline zirconia substrates, have been fabricated and tested at lambda = 10 mu m with a cw CO2 laser. A 2D thermal model for the bolometric response has been developed to include the film to substrate thermal boundary resistance, and take into consideration the various heat flow regimes inside the film and the substrate. This model has been found successful to predict both the amplitude and phase components of the bolometer response with respect to the modulation signal frequency. In particular, the amplitude response, which contains a succession of f(-1) and f(-1/2) sections separated by well-identified corner frequencies, could be quantitatively predicted in the 0.5 Hz to 100 kHz experimental frequency range.