Wide Spectral Response Nanocrystal-Sensitized Focal Plane Array

ABSTRACT: A compact night vision imaging technology will be developed that responds in the visible through the short-wavelength infrared (SWIR) and medium-wavelength infrared (MWIR) spectral range from 0.4 to 5µm wavelengths. The detectors are made using low cost deposition techniques, at atmosphere, using CMOS readout integrated circuits (ROICs). The imager does not require bump bond hybridization and is compatible with 5µm and smaller pixel pitches. In this effort SWIR sensitive nanocrystal quantum dot (NQD) films will be formed on an existing low noise 1k x 1k format CMOS ROIC, and its spectral responsivity, detectivity, lag and other optical performance metrics will be characterized. The ability to manufacture the nanocrystals at high volumes (kg/hour), at a cost only slightly above the chemical constituents, and to print the films at atmosphere, will also be demonstrated. We will demonstrate that the innovation can be scaled to larger format arrays (e.g., 4k x 4k and larger) and to small pixel sizes (<4µm). We will also demonstrate the ability to print vertical and mosaicked multi-spectral image and active/passive sensors. BENEFIT: The technology will benefit a wide variety of other military electro optical applications, including head mounted night vision imaging, missile seekers, and fire control systems. Commercial applications include surveillance imaging, cell phone camera, multi-spectral imaging, machine vision, industrial inspection, and others. This technology is significant in that we have reduced the cost of a finished focal plane array (FPA) from tens of thousands of dollars per wafer to tens of dollars, making FPA development highly affordable. Facile solution processing of NQD solid imagers also allows the potential for detector developments to proceed rapidly, reducing design cycle times from the multiple months required of bulk semiconductors to just a few days. Furthermore, solution processing also enables combinatorial detector material development. We have automated the NQD fabrication synthesis and deposition process, which makes material discovery, optimization, and development proceed rapidly tens of new materials can be made in a day.