Novel Photosensor for Scintillation Cameras

描述(由申请人提供)： 我们将开发一种用于核医学应用的19通道ANNG相机原型，它将基于一种新的固态光电探测器，取代目前使用的光电倍增管(PMT)。自20世纪50年代S以来，PMT在建造核医学伽马相机中的使用基本上没有变化。最近，包括我们在内的几个小组加紧努力开发各种类型的固态伽马相机，因为它们在性能、尺寸、重量和成本方面都有很大改进。到目前为止，基于固态探测器的伽马相机还没有实现所有这些目标，因为迄今为止探索的固态探测器技术的基本限制。由于其电容和漏电流，固态光电探测器的性能受到噪声的限制。在第一阶段，我们在开发雪崩硅漂移光电探测器(A+SDP)方面取得了重大进展，用于直接取代光电倍增管的愤怒相机。这些新探测器的主要优点是其极小的电容(与探测器大小无关)和低噪声。在第一阶段的工作中，我们在探测器设计方面进行了重大创新，将内部增益添加到漂移光电探测器中。这减轻了泄漏电流噪声，因此新器件不必冷却。在第一阶段，我们设计和制造了测试结构，证明了所提出的方法的可行性。 在第二阶段，将对新的雪崩漂移光电探测器设计进行优化，并将建造一个19通道安吉尔相机模块的原型。第二阶段将为原型相机开发完整的电子读数、机械封装和DAQ软件。原型探测器模块将与加州大学洛杉矶分校医学院的爱德华·霍夫曼博士合作，利用放射性同位素源和放射性同位素填充的模体，在能量分辨率、空间分辨率和灵敏度方面进行表征。第二阶段的开发将直接导致第三阶段用于核医学应用中的单器官成像的小视场ANNG相机的商业化。

DESCRIPTION (provided by applicant): We will develop a prototype 19-channel Anger Camera, for nuclear medicine applications, that will be based on a new solid-state photodetetor that replaces the currently used photomultiplier tubes (PMTs). The use of PMTs in the construction of gamma cameras for nuclear medicine has been largely unchanged since the 1950's. Recently there has been an intensive effort by several groups including ourselves to develop various types of solid state gamma cameras because they offer vast improvements in performance, size and weight, and cost. To date, gamma cameras based on solid-state detectors have not achieved all of these goals because of the basic limitations of the solid-state detector technologies explored so far. The performance of solid-state photodetectors is limited by noise due to their capacitance and leakage current. In Phase I, we have made significant progress on the development of avalanche silicon drift photodetectors (A+SDPs) for direct replacement of the PMT's in Anger cameras. The main advantage of these new detectors is their extremely small capacitance (independent of detector size) and low noise. During the Phase I effort we developed a significant innovation in detector design that adds internal gain to the drift photodetector. This mitigates leakage current noise, so that the new devices do not have to be cooled. In Phase I, we designed and fabricated test structures showing the feasibility of the proposed approach. In Phase II, the new avalanche drift photodetector design will be optimized and a prototype 19-channel Anger camera module will be constructed. Full electronics readout, mechanical packaging, and DAQ software for the prototype camera will be developed in Phase II. The prototype detector module will be characterized with respect to energy resolution, spatial resolution and sensitivity using radioisotope sources and radioisotope-filled phantoms in collaboration with Dr. Edward Hoffman at the UCLA School of Medicine. The Phase II development will lead directly to the Phase III commercialization of a small field-of-view Anger camera for single organ imaging in nuclear medicine applications.