Electronic structure of semiconductor detector surfaces and contact interfaces: Optimization of signal to noise ratio

We propose complementary experimental and predictive computational studies of the atomic and electronic structure and transport properties of CdZnTe (CZT)-based semiconductor detector surfaces and contact interfaces, which have received far less attention than the CZT bulk crystal quality issues. CZT is the most promising semiconductor for room-temperature x-ray and gamma-ray detectors which have a wide range of applications including interdiction of nuclear and radiologic materials. The objective of the proposed research is to (1) develop a fundamental understanding of the underlying atomic and electronic mechanisms responsible for the surface- and interface-related properties that degrade the performance of CZT radiation detectors, (2) ascertain the most efficient means of reducing or eliminating these effects, and (3) subsequently exploit this knowledge for the development of the next-generation CZT detectors to mitigate the effects of Weapons of Mass Destruction.