Optimization of room-temperature semiconductor detectors for energy-resolved x-ray imaging

We report on methods for optimizing room temperature semi-conductor detectors for energy-resolved x-ray imaging in radiology including applications such as computed tomography (CT), dual-energy x-ray absorptiometry (DEXA), and mammography. These applications produce high input count rates from an x-ray generator delivered to the detector. Room temperature semiconductors, operating as direct conversion x-ray sensors, can provide the required photon counting speed and energy discrimination when connected to application specific integrated circuits (ASICs) operating at fast peaking times with multiple fixed energy thresholds per electronic channel. Design can affect results dramatically at high output count rate (OCR) and optimization of the charge collection from the direct conversion sensors is required. Optimization of the ASIC to provide low noise, minimal power consumption and high count rate capabilities is required in parallel with the sensor optimization. We present our recent results with prototype detectors for CT, DEXA, and mammography.