A Polycrystalline Pixel Diamond Film Particle Detector

178 A Polycrystalline Pixel Diamond Film Particle Detector--Applied Science and Technology, Inc., 35 Cabot Road, , Woburn, MA 01801-1003; (617) 937-5135 Dr. Mathias Koch, Principal Investigator Mr. John M. Tarrh, Business Official DOE Grant No. DE-FG02-97ER82326 Amount: $71,483 Semiconductor detectors are used in high energy physics experiments to examine the collisions of particles and their subsequent trajectories. Current semiconductor detectors based on silicon have excellent detection characteristics but are susceptible to radiation damage. A promising alternative is a semiconductor detector based on polycrystalline diamond films which have good detection efficiency and excellent radiation hardness. As a result, the goal of this project is to utilize polycrystalline diamond thin films deposited on silicon or molybdenum substrates using microwave-enhanced chemical vapor deposition. These films will be tested to determine their quality and incorporated into existing detectors for evaluation. The objective of Phase I is to optimize film growth rate and quality, depositing films at high plasma power and plasma pressure from a variety of gas mixtures of carbon monoxide and methane. A diamond film grown over a Zinch area, at a thickness of 250 ¿m, will be produced and characterized, and an 8 x 8 pixel particle detector array will be fabricated on it over a 1 cm2 area. The objective of Phase II is the further optimization of the diamond film growth rate and quality to achieve characteristics necessary for practical applications in particle accelerators. Commercial Applications and Other Benefits as described by the awardee: The result of this project would be the development of the technology for commercial fabrication of diamond film particle detectors. Such detectors would be useful to high energy physics experiments around the world. Additional applications of this technology might be found in Positron Emission Tomography and x/gamma Radiation Visualization.