Project Description

GaAs diodes were first explored as coated neutron detectors by Prof. D.S. McGregor while at the University of Michigan. The basic design takes advantage of an electric field effect discovered and analyzed by McGregor for his Ph.D. research. Referred to as the 'truncated field effect', it was found that high electric fields could be sustained at a GaAs Schottky junction with a modest voltage, ranging from 10 - 50 volts. Further, the electrically active region increased across the diode with a linear voltage function, unlike typical pn junction diodes. As a result, low power devices can be fabricated for a relatively modest cost. Years later, Argonne National Laboratory (ANL) became interested in the coated neutron detector diodes being developed by McGregor for testing in their neutron beam ports, and purchased several devices from the S.M.A.R.T. Laboratory on a research contract. Since then, these outstanding detectors have been sent to several other DOE laboratories for various applications and testing, including Sandia National Laboratories and Lawrence Livermore National Laboratories.