Pyroelectric IR sensor based on oxide heterostructures on Si(100) and LaAlO3(100) substrates

Abstract

Uncooled infrared detectors consisting of thin film pyroelectric oxide heterostructures have been fabricated. Pb(Zr,Ti)O3 (PZT) and (Sr,Ba)Nb2O6 (BSN) thin films were integrated to YBa2Cu3O7-x (YBCO) films on yttria-stabilized zirconia (YSZ)-buffered Si(100) and on LaAlO3(100) substrates by the pulsed laser deposition technique. The YBCO thin films are used both as IR reflector- conductive electrodes and as atomic templates for PZT and BSN epitaxial growth, but not necessarily for their superconducting properties. The crystalline properties and photoresponse of the oxide thin film heterostructure infrared detectors were characterized from room temperature up to the phase transition temperatures of PZT and BSN. Detectivity values of approximately 108 cmHz1/2/W at room temperature have been obtained for simple heterostructure device configurations. The tunable phase transition temperature, dielectric constant and pyroelectric properties of the oxide allow for the development of an infrared detector with operation at temperatures higher than room temperature.