Thin Diamond for Time-of-Flight Detectors

Detectors and radiation monitors for future high energy and nuclear physics experiments must be able to withstand radiation environments several orders of magnitude harsher than those of any current device. At present, most radiation detectors are based on silicon technology, however, the practical radiation hardness limit of silicon falls far short of requirements in future high energy physics experiments. New radiation hard technologies must be developed to fill this gap and diamond has proven to be one such technology. Diamond radiation detectors have historically encountered restricted usage owing to the limitations of natural diamonds including small size, lack of control of the material characteristics and lack of control of surface properties. Recent advances in the growth of high quality Chemical Vapor Deposition (CVD) diamond have created relatively large sized, high purity polycrystalline diamond and an opportunity for the application of this material in practical detectors. This proposal addresses a need for detectors of large area and unusually uniform thickness. Optimizing the performance of diamond detectors in heavy ion nuclear physics will require providing high purity polycrystalline diamond with reduced grain boundary populations able to survive and perform at beam intensities approaching 108 particles/sec. We intend to design a process to make thin film diamond detector material, characterize it electronically and test it in a time-of-flight application. Success will enable us to look at processes for making the large areas of similar quality required for detectors at the dispersive focal plane of todays fragment separators. The proposed approach has the potential for a significant impact on nuclear physics research at facilities around the world. While solving an immediate and pressing problem for them, this technology will benefit users of 3rd and 4th generation light sources and enable the development of detectors to satisfy the future demands of the high energy physics community.