Description:
OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Microelectronics;Space Technology
The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.
OBJECTIVE: Develop a commercial supplier of infrared detector materials, readout integrated circuits (ROICS), and/or focal plane arrays (FPAs) optimized for multi-spectral-band operation. Designs should be constrained to operate through the infrared atmospheric transmission windows, specifically short-wave infrared (SWIR, 1-2.7 um), mid-wave infrared (MWIR, 3-5 um), or long-wave infrared (LWIR, 8-16 um). Materials and ROIC designs should be optimized specifically for multi-band operation (2 - 4 spectral bands in one or more atmospheric windows), with an emphasis on temporally simultaneous and/or spatially co-registered data capture. Additional consideration will be made for approaches that engineer radiation tolerance into the multi-band design to support both Air and Space Force applications. Solutions can include specific spectral-band combinations that serve a well-defined application (e.g. missile warning, target ID, gas sensing), or a modular product that can be adapted to a variety of multi-band applications.
DESCRIPTION: The commercial infrared imaging industry has grown tremendously in recent years, but all of the available commercial off-the-shelf infrared cameras are single band or color. Many industries currently utilizing single-band infrared imaging technology could benefit from a multi-band product that would generally provide improved discrimination and added functionality. For example, industrial manufacturers use single-color MWIR infrared cameras for imaging gas leaks. These cameras can be integrated with an optical filter designed to enhance contrast of a specific gas, but are limited in sensitivity by the environmental clutter of the scene and are blind to other gases. A two-color camera could dramatically improve the minimum detectable concentration of the gas, reduce false leak alarms, and provide improved visual fidelity of the gas by providing both a reference wavelength and gas-tuned wavelength. A three or four color camera could additionally detect and distinguish two or three different gasses all in a single camera. Similar cases can be made for industries such as defense, pharmaceuticals, health care, manufacturing etc. While dual-band FPAs have been demonstrated in the DoD, e.g. MWIR/MWIR and MWIR/LWIR, this was achieved using ROICs with two-color bias polarity switching. This approach utilizes alternating frames of each band and has several limitations: limited to two colors; detector array must be an epitaxial-grown stacked design; data capture is not temporally simultaneous; and generally works for broad-band channels with similar charge-handling requirements. For some applications, high quality identification/discrimination requires relatively narrow spectral bands (e.g. gas sensing), which is not easily realizable with the stacked design. Furthermore, many of these two-color ROICs use an analog pixel input with limited charge handling. This creates issues if bands have disparate charge handling requirements (e.g. SWIR with MWIR, or broad filter with narrow filter). Additionally, the detector designs and materials have not been optimized for multi-band imaging, which would ideally feature high absorption coefficients and sharp band edges to minimize optical cross-talk. Another recent technological growth area is in heterogeneous integration using vias, which have not been adequately explored in the context of multi-band FPAs. Solutions to this objective should be focused on providing a commercial supplier of enabling multi-spectral-band components (e.g. infrared detector materials, ROICs, integrated filter assemblies, or FPAs). The solutions should clearly define the innovation that makes the product particularly suitable for multi-band applications, and should be optimized for this purpose. While the main focus could be on optimizing detector materials or ROICs, for example, later phases of the program should include fabrication of full FPAs and/or cameras for demonstration purposes. Because innovations in multi-band imaging have utility for high-altitude and space-based applications, innovations that include some level of radiation hardness or tolerance will be given extra consideration. For proposals focused on ROIC design, there should be an emphasis on flexibility and functionality. As required, designs should consider the disparity in current handling requirements for both bias switched and/or super-pixel arrangements. This may require bias, integration time, and amplifier gain flexibility at the pixel and/or super-pixel level. Another consideration might be ROIC input layouts that accommodate detector arrays with spatially co-registered and simultaneous capture using via contacts. Solutions focused on back-end processing, such as integrated filter assemblies, must consider the current standard FPA manufacturing procedures and limitations to ensure product integration is effective, feasible, and not cost prohibitive. Because dual-band bias switched FPAs have been previously demonstrated, proposals that utilize this approach should also feature something that improves upon the design in a clearly innovative way.
PHASE I: Develop an innovative enabling component that improves state-of-the-art multi-spectral-band imaging capability. Identify applications for the enabling component, and use these applications to define performance metrics and requirements. Model the expected performance, yield/operability, and assess the commercial viability of the product. Determine expected challenges in fabrication/integration and provide mitigation approaches where appropriate. Start basic fabrication or other feasibility demonstration.
PHASE II: Produce and begin optimization of prototype component(s). Assess the operability and yield at this stage. Integrate with FPA and produce test data. Analyze the key performance metrics as defined in Phase I, and compare with current state-of-the-art. Identify partner(s) to develop a prototype demonstration camera utilizing the component for Phase III.
PHASE III DUAL USE APPLICATIONS: Refine the manufacturing process, optimize performance, and maximize operability/yield of the component. Build a prototype camera to demonstrate the functionality and performance of the component in a demonstration system. Compare performance to similar single color cameras with single optical filter and two-color bias switched designs. Focus on identifying interested FPA manufacturers and/or camera and systems integrators to transition the technology.
REFERENCES:
- Schwartz, Craig R., Jack N. Cederquist, and Michael T. Eismann. "Target detection using infrared spectral sensors." Imaging Spectrometry II. Vol. 2819. SPIE, 1996;
- Neele, Filip. "Two-color infrared missile warning sensors." Airborne Intelligence, Surveillance, Reconnaissance (ISR) Systems and Applications II. Vol. 5787. SPIE, 2005;
- Ariyawansa, Gamini, et al. "Unipolar infrared detectors based on InGaAs/InAsSb ternary superlattices." Applied Physics Letters 109.2 (2016): 021112;
- Carrasco, Rigo A., et al. "Proton irradiation effects on InGaAs/InAsSb mid-wave barrier infrared detectors." Journal of Applied Physics 130.11 (2021): 114501;
KEYWORDS: Infrared; Focal Plane Array; FPA, Image Sensor; Multi-Spectral; Multi-Band; Photodetector; Radiation Hard; ROIC; Readout Integrated Circuits;
