Development of Polarization Free CdZnTe Detector Arrays for Ultra-Fast Hyperspectral X-Ray Imaging

X-ray imaging has become an essential tool in various medical, industrial, and military applications. In its most advanced form, this method combines the shape information obtained in the imaging process with spectral information obtained bymeasuring theattenuation of the x-rays at different energies. Immediate discernment of material composition defects and anomalies at production rates in all kinds of products requires fast imaging. Therefore, ultra-fast hyperspectral imaging will be an important nextstep in this field. CdZnTe is the detector of choice at present for hyperspectral imaging because it works at room temperature with excellent energy resolution and it has a large atomic number (Z), which is essential for high sensitivity detection ofx-rays. However, polarization in these detectors at high x-ray rates is hampering the application of CdZnTe to hyperspectral imaging. We propose to study this effect in CdZnTe detector arrays and develop polarization free detector arrays for roomtemperature ultra-fast hyperspectral x-ray imaging. Commercial Applications: The first application we propose is for automatic baggage inspection for contraband such as explosives, agricultural products, drugs and currency. Today, baggage inspection islimited to transmission/absorption image reconstruction. To detect, identify, characterize and quantify the various items, the system must also be able to detect and quantify the energies of the characteristic x-rays that are produced by the items in thebag, box or container.Federal Government Use: High-quality, CZT-based, detection systems can be used by both government and industry. Baggage inspection is a prime example of government use. Other applications, such as the medical and industrial imaging,are also of major interest to federal, state, and local government agencies. Therefore, the government sector can be a major market for the proposed detector system.