Technology of multiquantum well infrared detectors

During the last decade, the QWIPs technology has improved from start to an undeniable maturity level. High performance focal plane arrays have already been realized (ATT, Lockheed-Martin, JPL,...) viith a spectacular formal increase ranging from 128 x 128 up to 640 x 480, and images from bicolor 256 x 256 arrays have been shown last year. All these devices illustrate the high potential of the QWIP technology, In the same time, the modeling of detection mechanisms has advanced to permit the present design of specific detectors and their optimization in given operating environments (near 77 K detector temperature for instance). In this communication, we will summarize our recent technological studies leading: to the next generation of very large infrared detector arrays. We will present the QWIP ultimate performances allowed by the standard dual III-V technological processes developped at THOMSON CSF, in terms of pixel size, array filling factor or connectics. The influence of the pixel size for the grating optical coupling is analyzed. We will finally include in this analysis our results for more complex devices like multispectral infrared detectors.