WHITE PAPER ANSWERS TO QUESTIONS ON MCT'S ADVANTAGES AS AN INFRARED IMAGING MATERIAL Leonardo DRS, Electro-Optical & Infrared Systems Leonardo DRS, Electro-Optical & Infrared Systems White Paper Answers to Questions on MCT'S ADVANTAGES AS AN INFRARED MATERIAL – Leonardo DRS, Electro-Optical & Infrared Systems Cooled infrared imaging is in many only Leonardo DRS but also Raytheon, Answers to Questions on MCT’s ways a mature technology, with Teledyne, SOFRADIR, SELEX Galileo, its architectures well-defined and AIM and SCD, continue investing Advantages as an Infrared Imaging its past and present applications in MCT’s present reality and future Material well-understood. Nevertheless, potential. Q1. What advantages can we expect opportunities abound for: DRS has been at the forefront of this from DRS MCT? • Improving range and resolution effort for many years. As a world DRS’ Mercury Cadmium Telluride while reducing cost, device size, leader in electro-optical infrared (EO/ (MCT), also known as HgCdTe, weight and power (SWaP). IR) imaging for military applications, provides three overriding we have a proud history of meeting advantages as an infrared • Expanding IR imaging’s our Warfighters’ mission- critical IR imaging material. applications for users in the military, imaging needs in even the harshest First and most important is homeland security and commercial environments. And we have fielded its ability to deliver optimal well over 100,000 DRS EO/IR systems realms. performance at higher operating on all major ground-vehicle, airborne Perhaps no other variable is as temperatures than InSb, for and maritime platforms – including important to this equation as the size, weight and power (SWaP) more than 70,000 MCT-based devices. detector material itself. Today, many reductions and improved thermal users, industry leaders and scientists DRS can arguably take much of the management. agree that the best semiconductor credit for making MCT affordable, Second, it takes advantage of the material for capitalizing on these for resolving its early performance industry’s smallest pixels, leading opportunities is Mercury Cadmium and fabrication challenges, and to proportionate increases in Telluride (MCT), or HgCdTe. The for demonstrating its across-the- range, reductions in optics primary reasons: board superiority over other detector materials. size, or improvements in spatial • MCT is proven, reliable, and readily resolution – or a combination of available. In this document, we’ll answer the these advantages, tailored to the most commonly asked questions about application. • Its cost is now highly competitive DRS MCT’s key attributes, advantages with common indium antimonide and limitations. If we can answer And lastly, it provides access to (InSb). any more for you, please contact us such emerging applications as active and passive shortwave • It offers users significant soon. You can reach us by calling 1-888.230.2372, by emailing sales@ infrared (SWIR), two-color, 3D advantages over InSb in terms drsinfrared.com, or by visiting us at and active imaging, as well as of range, resolution, device size, www.drsinfrared.com. the possibility of cooled handheld weight and power requirements – in MWIR devices to make superb short, the best performance-to-cost image quality truly portable. value. Q2. Why did DRS choose MCT over • It is already demonstrating its utility InSb? for advanced applications such as Indium antimonide (InSb) is one of several focal plane array two-color and active imaging and (FPA) materials for infrared shows promise for SWIR imaging. imaging. However, because of These are among the reasons that its limitations, scientists have so many major players, including not continued advancing other FPA materials. MCT is arguably the 2 Leonardo DRS, Electro-Optical & Infrared Systems White Paper most important of these materials. Temperature Infrared (HOT-IR™) of MCT has reduced its price to MCT detector technology, which levels comparable to InSb’s. The scientists at Texas can perform at significantly Instruments (TI) who developed Until recently, MCT detectors had elevated temperatures to first-generation IR devices have a slightly higher percentage of minimize these trade- offs. been among the leaders in this “dead” pixels, which could impact effort. They anticipated game- Five years in the making, the quality of the infrared image. changing advantages from MCT, HOT-IR™ means that the detector The seriousness of this issue in large part because it’s the only does not need to be cooled may have been exaggerated; known material that can detect IR down to 77°K. Instead, HOT-IR™ the actual operability difference radiation in all three atmospheric delivers superior performance at between MCT and InSb was windows – shortwave (1.5-1.8 temperatures well above 110°K always under 0.1%. Nevertheless, and 2.2-2.4 micron), midwave resulting in significantly less MCT’s operability is now at 99.5% (3-5 micron) and longwave (8-14 power required. -- equal to or better than InSb. micron). While the precise operating DRS continues to set new Recognizing this unique temperature is company- performance standards for MCT characteristic, TI made confidential, we can say that with such developments as these: major investments in MCT’s our HOT-IR detectors use development over the years, even smaller coolers and consume • Vertically Integrated as the organization underwent less power. And that adds up to Photodiode (VIP) and High various divestitures and substantial reductions in size, Density VIP (HDVIP™) focal- acquisitions to ultimately become power requirements, and cooler- plane array architectures for a part of Leonardo DRS. DRS has generated heat, as well as a mono- and multi-color next- continued this investment. tripling of cooler life – from under generation systems 10,000 hours to 30,000 hours or Today, this pioneering work is more. • Very small-pitch, high-density paying off. DRS scientists have formats overcome MCT’s initial cost and Q4. Why should we consider operability disadvantages, letting choosing MCT over InSb or • Ultra-high operating its advantages take center stage. other technologies? temperatures Many in the industry now consider For years, there have been • Active/passive FPAs providing MCT the preferred material for drawbacks associated with noiseless gain cooled IR imaging applications. MCT, mainly in terms of power consumption, relatively high cost • Very large-area FPAs Q3. How high an operating temperature can MCT and occasionally inconsistent Other materials have emerged, accommodate? performance. DRS was able including Quantum Well Infrared to overcome these challenges Photoconductor (QWIP) and MCT requires cryogenic and is setting new performance such nanotechnology products cooling in order to minimize standards for MCT. as Quantum Dot Infrared Photo- the background noise from the detectors (QDIPs). However, “dark current” produced in the DRS’ HOT-IR MCT detectors their performance at comparable detector material itself – and require as little as one-third the temperatures can’t match MCT’s, therefore to achieve the ultra-high power needed by comparable and DRS is convinced that MCT performance needed for today’s InSb devices. For example, will remain the most effective and military and security applications. the power consumption of our cost-efficient solution for cooled 12-micron HOT-IR MWIR camera Cooling has a cost, of course, in infrared imaging. is just 7.5 watts steady-state. terms of size, weight and power Compare this to the 15 to 25 watts Unlike most other detector (SWaP), heat generation, and of steady-state power required suppliers, DRS enjoys complete potential cryogenic reliability by coolers for equivalent InSb control over the entire process, concerns. As lower temperatures cameras. from growing our own CZT are required and cooling substrate material to assembling requirements increase, larger The high cost of MCT was the detector/cooler package. coolers are needed, resulting in primarily the result of challenges Because we focus on optimizing greater power requirements. with composition control and a single material, we’re able to low yields. With technological However, DRS has developed deliver world-class results. advances, DRS’ high throughput extraordinary High Operating 3 Leonardo DRS, Electro-Optical & Infrared Systems White Paper As a result, DRS has succeeded (FOV) and 20% increase in the Its shorter wavelengths allow in overcoming challenges and magnification of the most distant sharper image quality and/or a expanding the capabilities of scenes you can capture. smaller optical aperture to reduce MCT to produce environmentally SWaP, especially advantageous Resolution and range responsible products of in applications such as airborne. improvements are especially the highest quality, at costs important in military applications. In high humidity applications such comparable to InSb’s. Higher resolution helps our troops as in marine/littoral environments, Q5. Why have you gone to identify a threat when it’s farther MWIR contrast remains high 12-micron pitch? away, giving them more time for greater ranges than LWIR. Among the most important to respond appropriately and Airborne sightlines avoid much of traits of DRS’ approach to FPAs effectively. And a longer range the MWIR blurring that is present is its ability to accommodate can make it easier for them to in the turbulent layer near the smaller pixels than InSb. DRS is operate while staying out of ground. harm’s way. producing MCT detectors