Applications of ferroelectrics in uncooled thermal imaging. II

Summary form only given. This paper will continue the description of the use of ferroelectric detectors in uncooled thermal imaging from Pt. I which concentrated on the present generic range of hybrid detector arrays. The new research centred around an integrated technology for the ferroelectric arrays will be described. In this technology, the ferroelectric detector material is directly deposited onto the silicon readout IC (ROIC) by either sol-gel processing or sputtering. To thermally isolate the elements from the ROIC, the ferroelectric is deposited onto a sacrificial layer and patterned so that, on etching, a thin microbridge of the ferroelectric and its electrodes is constructed standing on two narrow legs above the silicon surface. The technology should lead to full wafer scale production with no ceramic preparation, reticulation or bonding giving substantial cost reductions and improved performance in comparison with the hybrid arrays. Topics being addressed are the ferroelectric films, and the bridge micro-engineering and materials. The present hybrid array programme description will be concluded with a video tape of scenes from the application of the 100×100 array to fire-fighting in the helmet mounted CairnsIRIS system, and of the 256×128 array to night driving in simple trials