Uncooled Thin Film Infrared Imaging Device with Aerogel Thermal & dGqgD $ J ? - Deposition and Planarization Techniques 0971

:mCl Quum INSrnCrnD3 Abstract We have successfully integrated a thermally insulating silica aerogel thin film into a new uncooled monolithic thin film infrared (E) imaging device. Compared to other technologies (bulk ceramic and microbridge), use of an aerogel layer provides superior thermal isolation of the pyroelectric imaging element from the relatively massive heat sinking integrated circuit. This results in significantly higher thermal and temporal resolutions. We have calculated noise equivalent temperature differences of 0.04-0.10 "C from a variety of PbXZryTi,,O3 (PZT) and PbxLa,~xZryTi,-yO, (PLZT) pyroelectric imaging elements in monolithic structures. In addition, use of aerogels results in an easier, less expensive fabrication process and a more robust device. Fabrication of these monolithic devices entails sol-gel deposition of the aerogel, sputter deposition of the electrodes, and solution chemistry deposition of the pyroelectric imaging elements. Uniform pyroelectric response is achieved across the device by use of appropriate planarization techniques. These deposition and planarization techniques are described. Characterization of the individual layers and monolithic structure using scanning electron microscopy, atomic force microscopy and B yer-Roundy techniques also is discussed.