Proceedings Article | 7 June 2024
A. Magid, L. Shkedy, N. Ben Ari, N. Shiloah, C. Jakobson, W. Freiman, E. Armon, E. Almog, S. Srur, A. Katz, N. Ashush, G. Tzvieli, M. Alcheck, J. Lazarus, O. Magril, O. Dicker, B. Milgrom, T. Markovitz
KEYWORDS: Staring arrays, Readout integrated circuits, Sensors, Mid-IR, Modulation transfer functions, Quantum efficiency, Video, Power consumption, Design
In modern, wide distribution, defense and commercial applications, such as hand-held cameras and small payload systems, a High Definition (HD) Mid-wave Infrared (MWIR) detector is desired. This is to provide both a wide Field of View (FOV) and / or an extended range of Detection, Recognition and Identification (DRI). At the same time, many of these applications also require a solution that is of low Size Weight and Power (SWaP) and with a high degree of reliability.
Typically, the requirements for a large, cooled HD array conflict with those for low-SWaP and high reliability. To overcome this challenge, SCD developed a new state-of-the-art detector that is based on the Sparrow-HD Focal Plane Array (FPA). The Sparrow-HD MWIR FPA has a 5μm pixel and 1280x1024 format. The FPA includes an advanced Readout Integrated Circuit (ROIC) that has several operation modes, such as standard video output at low power consumption, high frame rate output (detection mode), multiple types of binning modes, a high sensitivity mode and more. All operation modes can be controlled via communication from the host system. The Sparrow HD ROIC is bonded to a High Operating Temperature (HOT) XBn-InAsSb IR-sensing material that operates at 150K. This material is sensitive to the 'blue' part of the MWIR spectrum where the atmosphere is most transparent and represents a mature SCD technology. The ability to operate at 150K greatly supports both the low SWaP requirement and the requirement for extended cooler reliability.
One of the development challenges of a 5um pitch FPA is the ability to maintain high electrooptical performance for such a small pixel. It is shown in this article that the Sparrow-HD FPA maintains a level of electro-optical performance that is similar to SCD's 10μm pitch Sparrow 640×512 FPA, including high quantum efficiency, low dark current, low cross talk, high array uniformity, and high operability.
At the detector module level, the small size and low power FPA enables the use of a highly reliable compact dual-piston split-linear cryogenic cooler, and low-power proximity electronics. Hence, the Sparrow HD module is one of the lowest SWaP sensors available in the industry today. The key characteristics and performance of this new module are detailed herein including its compatibility with a large variety of IR applications.
Overall, the Sparrow-HD module brings HD resolution to all compact tactical systems that previously were limited to VGA solutions in terms of detector SWaP, Cost and Performance.