Fabrication of un-cooled infrared sensor using pyroelectric thin film

In the conventional IR-sensors (infrared sensor), there are problems of needing cooler and sensing wavelength limitation. These problems can be achieved by using un-cooling thermal IR sensors. However, they raise the problems of the attack of pyroelectric thin film layer during the etching of sacrificial layer as well as the thermal isolation of the IR detection layer. In order to fabricate uncooled IR-sensor using pyroelectric film, multilayer should be prepared pyroelectric thin film and thermally isolating membrane structure of square-shaped microstructures. We used the direct bonding technique to avoid the thermal loss by silicon substrate and the attack of pyroelectric thin film by etchant of the sacrificial layer. Metallic Pt layer used as a top and a bottom electrodes were deposited by E-beam sputtering method, while pyroelectric thin films were prepared Sol-Gel techniques. Because the pyroelectric thin film with c-axial orientation raised thermal polarization without the polling, the more integrated capability could be achieved. We investigated the characteristics of the pyroelectric thin films.: P-E loop, dielectric constant, XRD (X-Ray Diffractometry) etc.