Effective heat conservation in a sandwich-structured microbolometer using mesoporous TiO2 layers

Abstract

The heat loss of the a-Si:H resistor layer in a microbolometer might be reduced by using ordered mesoporous TiO2 thin films as thermal insulation layers. Infrared absorption of mesoporous TiO2 thin films in the 833-1250 cm(-1) wave number region Was Measured using a Fourier transform infrared spectrometer. Also, the infrared absorption rates of upper and lower mesoporous TiO2 films inserted into the microbolometer were calculated to be above 84% in the 8-12 mu m wavelength region. The CFD-ACE thermal simulation program Was used to evaluate the thermal isolation effectiveness of mesoporous TiO2 films on the a-Si:H layer: the inclusion of this film on the a-Si:H layer improved heat conservation. A mesoporous TiO2 thin Him effectively reduced the thermal loss from a-Si:H resistor surface and drastically increased the temperature of the resistor film. (C) 2009 Elsevier B.V. All rights reserved.