Spray etch recess process for high yield analog GaAs MMICs

Gate recess spray etch and bath-immersion etch processes are compared in the manufacturing of high yield analog GaAs MMICs. Detailed experiment work together with statistical analysis have determined the superiority of the spray etch process over the bath-immersion process. Optimization and implementation of the spray etch process in a three-inch GaAs wafer fabrication line are discussed. Improvements in device current uniformity, circuit RF test yield, and overall yield are demonstrated for the spray etch recess process, in the production of GaAs MMICs.<>