26 October 1998 First MPQ IRFPA results using LCR/SOFRADIR technologies
Author Affiliations +
The Laboratoire Central de Recherches (LCR) of Thomson Csf and the Societe Francaise de Detecteurs Infrarouge (Sofradir) combined their complementary skills to realize a MultiQuantum Well Infrared Photodetector (QWIP) Focal Plane Array (FPA) sensitive in the long wavelength range of the spectrum (LWIR). Sofradir has industrialized a versatile indium bump hybridization technics qualified for operations as low as 50 K and mostly dedicated to connection of Cadmium Mercury Telluride (CMT) PhotoVoltaic (PV) detectors to silicon Read- Out Integrated Circuits (ROIC). On the other hand, the Thomson Csf/Lcr's QWIP technology based on GaAs/AlGaAs heterostructures is now suitable for industrial development. The device described in this paper is a first generation 144 X 192 MQW staring arrays with a 50 microns pitch; it is operated at temperature as high as 80 K. Such a high operating temperature can be achieved thanks to the optimized design of the QWIP active layer and to the use of a multi purpose experimental CMOS ROIC integrating a current skimming function; this structure developed for high temperature operation of CMT detectors allows for in pixel calibration and derivation of photosite current containing no scene information (e.g. dark and background current) and thus offers enhanced effective storage capacity. In this paper, the main features of the hybrid are given showing the adequacy of this hybridization technics to connecting the QWIP structures. A functional description of the ROIC is presented together with its advantages and limitations in terms of conditions at operating temperature of 70 K and 80 K are thoroughly presented and discussed, in particular in reference with the equivalent CMT performances.
© (1998) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Michel Vuillermet, Christophe Minassian, Bernard Pitault, Philippe Francis Bois, Eric M. Costard, and Julien Nagle "First MPQ IRFPA results using LCR/SOFRADIR technologies", Proc. SPIE 3436, Infrared Technology and Applications XXIV, (26 October 1998); doi: 10.1117/12.328022; https://doi.org/10.1117/12.328022

Back to Top