AST-9532046 Summary: The objective of this project is to develop millimeter-wave integrated circuits (MMIC's) with high sensitivity and low replication cost to enable the fabrication of focal-plane arrays with 50 to 1000 pixels for use in radio astronomy. These arrays should have noise temperatures competitive with the best single pixel receivers using SIS mixers, but with vastly lower cost and simpler operation. The project has a wide scope to cover many aspects of focal- plane array systems. The following topics are included: 1) Optimization of high-electron-mobility transistor (HEMT) material composition to provide lowest noise at cryogenic temperatures. 2.) Design, fabrication, and testing of MMIC low-noise amplifiers to cover the bands of 33-50, 65-90, and 85-115 GHz. A minimum of 30 MMIC's of each type will be made available as samples for evaluation at radio astronomy observatories.
