Domestic Scalable Growth Of Large-Format Pixelated CZT Crystals For Advanced Radiation Detection

SBIR topic DTR27BZ02-NV006 (U.S. Department of Defense – DTRA), Phase I and II. Open to U.S. small businesses. Opens: December 2, 2026. Closes: January 6, 2027. Compact, high-resolution, room-temperature gamma imaging and spectroscopy systems are critical for a number of government agency applications (DoW, DTRA, DOE/NNSA, IAEA, DHS), in addition to a number of commercial applications (nuclear power, medical community). CZT-based 3D position-sensitive detectors provide these capabilities without cryogenic cooling, leveraging the small-pixel effect and depth-of-interaction (DOI) sensing via pixelated anodes and timing readout. Current advanced systems rely on high-quality pixelated CZT, but most commercial modules use smaller crystals (~20–22 mm lateral dimensions). Furthermore, finished crystals with a thickness of around 5 mm are readily available for medical imaging; however, thicker crystals are often available from manufacturers by long-lead, custom order. Scaling to monolithic 44 × 44 × 15 mm crystals would significantly increase intrinsic efficiency (particularly for higher-energy gamma rays), reduce the number of crystals and interfaces per imager, improve geometrical coverage, simplify module assembly, and lower overall system complexity while maintaining or exceeding energy resolution targets of <1% FWHM at 662 keV. High-performance spectrometer-grade CZT at this scale is currently supplied primarily by a limited number of foreign or foreign-owned sources, creating recognized supply-chain vulnerabilities for critical national security radiation detection hardware. Tellurium feedstock is heavily concentrated overseas, and domestic high-end crystal growth capacity remains limited. Zinc and Tellurium are identified in the U.S. Geological Survey (USGS) 2025 List of Critical Minerals. Additionally, Executive Order 14415 "Securing America's Defense Supply Chains and Ensuring Domestic Acquisition of Critical Materials" (July 20, 2026), and related DoW supply…