Next-Generation Active Pixel Sensor Device with CMOS Avalanche Photodiodes

78820S Modern high-energy physics experiments that explore the fundamental properties of matter rely on large, sophisticated instruments for tracking particle decay events with large detector arrays. However, the performance of these instruments is limited by available detector technology. Future progress depends on breakthroughs in the sensitivity, speed, and signal-to-noise performance of the detectors. This project will investigate designs for a vertex particle detector that uses Active Pixel Sensors (APS) with Avalanche PhotoDiode (APD) junctions designed in a CMOS (complementary metal-oxide semiconductor) environment. The viability of the CMOS APD technology for this application will be based on sensitivity, speed, and signal-to-noise performance in the tracking of primary or secondary decay events created in particle collisions. Phase I will demonstrate the feasibility of using CMOS APD pixels for particle tracking in a CMOS APS device by designing, fabricating, and characterizing prototype detector cells. Several different pixel and circuit designs will be explored in the prototype. Testing with different types of radiation will allow the different designs to be characterized, and the best design will be selected. Commercial Applications and Other Benefits as described by the awardee: The technology should find use in planned upgrades of current vertex detectors (PHENIX, STAR, SLAC, etc.), in a next-generation linear collider, and any other experiments that track particles. Improvements in the device technology can also be used to improve detection in medical applications and x-ray crystallography.