Large-format broadband multicolor GaAs/AlGaAs quantum well infrared photodetector (QWIP) focal plane arrays

Abstract

The GaAs/AlGaAs based quantum well IR photodetectors (QWIPs) afford greater flexibility than the usual extrinsically doped semiconductor IR detectors because the wavelength of the peak response and cutoff can be continuously tailored over any wavelength between 6-20 micrometers . The spectral band width of these detectors can be tuned from narrow to wide allowing various applications. Also, QWIP offers multi-color IR cameras which is capable of simultaneously acquiring images in different IR bands. Each pixel of such array consists of vertically stacked, independently readable, QWIP detectors sensitive in different narrow IR bands. In this article, we discuss the result of a 10-16 micrometers large format broadband QWIP focal plane array IR bands. In this article, we discuss the results of a 10-16 micrometers large format broadband QWIP focal plane array (FPA). The size of the FPA is 640 X 512 and its pixel pitch is 25 microns. The highest operating temperature of the FPA is 45K, and it was determined by the charge storage capacity and the other features of the particular readout multiplexer used in this demonstration. Excellent imagery, with a noise equivalent differential temperature of 55 mK has been achieved. In addition, we will discus the developments and results of the 640 X 512 dual-band QWIP FPA.