A novel very high resolution Positron Emission Tomography (PET) detector module consisting of a monolithic 64-element array of silicon avalanche photodiodes (APDs) coupled to a 64-element bismuth germanate (BGO) scintillator array with custom integrated front-end electronics incorporated directly into the package will be developed, manufactured and characterized. The new detector module will have higher resolution than any currently available commercial PET detector. A small bore prototype PET scanner using the new detector module will be manufactured and characterized. Since APDs can be fabricated using semiconductor processes that are intrinsically less expensive and more reliable than the techniques used to build photomultiplier tubes (PMTs), detector arrays built using APDs may be the only cost-effective means of achieving the higher resolution needed to improve the detection and localization of PET. Because each detector element in the new module will require its own high- speed, low-noise signal processing circuitry, the front end electronics must be implemented in custom integrated circuits in order to achieve the necessary circuit density. The integrated circuits will be mounted to the back of the APD array, greatly reducing the volume of the detector module over conventional PET detector/electronic configurations.
