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Bolingbrook, IL, United States

Grant
Agency: Department of Defense | Branch: Defense Advanced Research Projects Agency | Program: STTR | Phase: Phase I | Award Amount: 100.00K | Year: 2014

The primary goal of this proposed effort is to develop mid-wavelength infrared (MWIR) colloidal quantum dot (CQD)-based focal plane arrays (FPAs) to significantly reduce the cost of MWIR photon imagers. In order to realize this goal, it will first be nec


Grant
Agency: Department of Defense | Branch: Missile Defense Agency | Program: SBIR | Phase: Phase I | Award Amount: 123.34K | Year: 2015

Absorber layers based on Type-II superlattices (T2SLs) composed of III-V compound semiconductors (e.g. GaSb and InAs) are a promising sensor technology for infrared imaging; however, dark currents and short carrier lifetimes in the Ga-containing T2SL are significant problems. It is presently suspected that the short carrier lifetimes and some dark current arise due to a native point defect, possibly the Ga antisite (a Ga atom on the Sb sublattice), creating a mid-gap state within the T2SL band gap that facilitates Shockley-Read-Hall generation/recombination. We propose to use first principles calculations to verify the suspect defect and evaluate its impact on lifetimes and dark currents, and study its impact as a function of position within the superlattice period. Other native defects will also be examined. Molecular dynamics molecular beam epitaxy growth simulations will then be used to evaluate growth strategies that minimize the concentration of the key defects. Experiments will then be performed to verify the theoretical understanding and optimize a growth process based on the theoretical predictions. Approved for Public Release 14-MDA-8047 (14 Nov 14)


Grant
Agency: Department of Defense | Branch: Missile Defense Agency | Program: STTR | Phase: Phase I | Award Amount: 149.98K | Year: 2011

Current state-of-the-art infrared focal plane arrays (IRFPAs) are based on HgCdTe material epitaxially grown on bulk CdZnTe substrates. The size of the IRFPAs is limited by the size of the available CdZnTe substrates and the thermal mismatch between CdZnTe and the Si readout circuit, which misaligns the photodiode array with respect to the circuit during heating and cooling cycles. Having HgCdTe fabricated on Si-based composite substrates would eliminate the aforementioned drawbacks related to the HgCdTe/CdZnTe system. Indeed, the use of Si-based substrates would also lower imager costs. While a large effort has been put forward to improve the quality of the HgCdTe grown on CdTe/Si, there still remains much room for further advancement. In the proposed effort, Episensors will develop new and innovative chemical mechanical polishing slurries and cleaning techniques that will yield higher quality Si(112) substrates. CdTe/Si layers will be grown in-house via molecular beam epitaxy and the growth of HgCdTe on CdTe/Si will take place at the University of Illinois at Chicago. We will employ advanced methods for characterizing the materials and devices to provide feedback for process optimization.


Grant
Agency: Department of Defense | Branch: Missile Defense Agency | Program: SBIR | Phase: Phase I | Award Amount: 99.79K | Year: 2015

We propose to develop a non-destructive test method to identify and quantify the formation of red plague corrosion within an insulated silver-plated copper wire. Cross-linked ethylene-tetrafluoroethylene (XL-ETFE)-insulated silver-plated copper wire demonstrates high performance and is commonly used in military and aerospace applications as hook-up and lead wire, but is prone to galvanic corrosion that can lead to unpredictable in-flight failures after only 10 years of life. There is currently no acceptable method to determine the extent of corrosion in a silver-plated copper wire. Our proposed approach for red plague corrosion detection is to transmit a well-defined signal through the wire and accurately measure the output signal. By employing sophisticated analysis techniques, we will identify the signature of red plague corrosion and quantitatively calibrate it with the extent of corrosion present in the wire. Our approach to the measurement and analysis provides the sensitivity needed to detect early stages of corrosion while reducing the potential for erroneous detection. With the proposed development of a highly-sensitive and accurate test method to quantitatively detect red plague corrosion within an insulated silver-plated copper wire, we will establish the foundation of a novel commercial test system. (Approved for Public Release 15-MDA-8482 (17 November 15))


Grant
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 97.45K | Year: 2015

Absorber layers based on strained layer superlattice (SLS) composed of III-V compound semiconductors (e.g. GaSb and InAs/Sb) are a promising sensor technology for infrared imaging; however, dark currents and short carrier lifetimes in SLS are still significant problems. It is presently suspected that the short carrier lifetimes and some dark current arise due to a native point defect, possibly the Ga/In antisites (a III-group atom on the V-group sublattice), creating a mid-gap state within the SLS band gap that facilitates Shockley-Read-Hall generation/recombination. Sivananthan Laboratories, Inc. proposes to use molecular dynamics simulations to evaluate the types and distributions of defects as a function of MBE growth parameters, and tight binding electronic structure calculations to evaluate the effect of defects on lifetimes and hence dark currents, thus producing a fully computational method to relate MBE process parameters to device performance. Possible growth process improvements will be considered, based on the identified deleterious defects and associated process parameters, and tested using the proposed computational method. Experiments will then be performed to verify the theoretical understanding and optimize a growth process based on the theoretical predictions.

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