ASGRAD FY07 Annual Report (open access)

ASGRAD FY07 Annual Report

This is the annual project report for the ASGRAD project - Amorphous Semiconductors for Gamma Radiation Detection. We describe progress in the development of new materials for portable, room temperature, gammaradiation detection at Pacific Northwest National Laboratory. High Z, high resistivity, amorphous semiconductors are being designed for use as solid-state detectors at near ambient temperatures; their principles of operation are analogous to single-crystal semiconducting detectors. Compared to single crystals, amorphous semiconductors have the advantages of rapid, cost-effective, bulk-fabrication; nearnet-shape fabrication of complicated geometries; compositional flexibility; and greater electronic property control. The main disadvantage is reduced-charge carrier mobility. The focus of this project is to develop optimized amorphous semiconductor materials for gamma detection applications that leverage their material advantages while mitigating their limitations. During the second year of this project, several important milestones were accomplished. Major accomplishments were: (1) Significant processing - property and composition - property correlations were determined for Cd-Ge-As glasses; (2) Radiation response testing was successfully demonstrated on three different amorphous semiconductor materials (Cd-Ge-As, As-Se, and As-Se-Te systems) at ambient and near ambient temperatures; (3) Advanced, enabling Schottky contacts were developed for Cd-Ge-As compounds, this will allow these materials to perform at ambient temperatures; and (4) The collaborative …
Date: May 6, 2008
Creator: Johnson, Bradley R.; Riley, Brian J.; Crum, Jarrod V.; Sundaram, S. K.; Henager, Charles H.; Seifert, Carolyn E. et al.
System: The UNT Digital Library