This award will support collaborative research in electrical engineering between Dr. Ting-Wei Tang, University of Massachusetts and Professor Erik Kollberg, Department of Applied Electron Physics, Chalmers University of Technology, Goteburg, Sweden. The project will focus on the study of excess noise in GaAS Schottky-barrier diodes, designed for millimeter waves and mixers. Solid experimental evidence on the existence of excess noise in millimeter wave diodes related to hot electron effects has been collected by Chalmers research group. This group has competence in both the fabrication of GaAs millimeter wave diodes and noise measurements from frequencies of a few hundred MHz to about a hundred GHz. However, a theoretical understanding of the diode noise characteristics versus bias current is generally lacking. The University of Massachusetts group is well-known for its numerical modeling of hot-electron and other effects in semicon- ductor devices. The proposed research will aim at: l) a detailed theoretical model (to be developed utilizing the numerical modeling expertise available at the University of Massachusetts), and 2) an experimental verification (using Swedish expertise on fabricating high quality Schottky diodes). The results of this project are expected to lead to improved designs of low-noise Schottky-barrier diodes for millimeter wave application.
