Modular sensor pack for large thickness cadmium zinc telluride (CZT) Gamma Radiation detectors

The high cost of fine spectroscopic grade CZT crystals with large gamma-ray stopping power is a limiting factor for widespread utilization in detector applications. Large volume, monolithic crystal parts suffer a lower yield because of high probability of defect opportunities. This work demonstrates a modular construction technique where volumetric scaling laws are overcome. Smaller crystal tiles are individually diced, graded and then bonded into a larger sensor package that achieves high stopping power. Choosing a common tile form factor for both healthcare and security imaging applications ensures the most efficient use of CZT wafer area by matching tile performance to application requirements. Gamma spectroscopic measurements results demonstrate that high quality detectors can be achieved in these sensor packs. The modular sensor pack is effective to circumvent the problem of low yield due to growth inhibition of a large-size, high quality crystal.