Abstract: State-of-the-art infrared (IR) photon detection is accomplished using III-V or II-VI compound semiconductors such as HgCdTe, InGaAs, and InSb, among others. These materials feature low dark current densities and high external quantum efficiencies but must be cryogenically cooled, crystalline, and require flip-chip hybridization to readout integrated circuits (ROIC). These requirements add cost and complexity to IR detection systems. Newer technologies such as strained layer superlattices and other high operating temperature IR sensors can use thermoelectric cooling but still require epitaxial growth and hybridization. We have recently began developing IR sensors using classical doped, conjugated polymers as well as newer materials such as open shell, triplet diradical conjugated polymers which have intrinsic electrical conductivity. Our polymer-based IR sensors are principally active in the shortwave infrared (λ = 1-3 μm), with response extending well into the midwave infrared (λ = 3-5 μm) and longwave infrared (λ = 8-14 μm). This new generation of very low cost IR sensors will enable hybrid-free detectors where the materials are disordered semiconductors; they can be deposited using spin-coating, drop-casting or oxidative chemical vapor deposition directly onto a ROIC. This eliminates the need for hybridization and epitaxial quality materials. The detectors operate at room temperature, also eliminating the need for cooling. Current device challenges principally involve fabricating vertical (parallel) detector geometries and dark noise reduction.

Biography: Jarrett Vella is a Senior Research Chemist in the Electro-Optical and Infrared Components Branch of the Sensors Directorate, Air Force Research Laboratory. He obtained his Ph.D. from the University of Florida and received postdoctoral training at the Materials and Manufacturing Directorate, Air Force Research Laboratory. His research seeks to identify ultralow cost infrared sensors with minimal size and weight requirements for use in terrestrial and space applications.