Production Worthiness of a GaAs Wafer FAB as Demonstrated Through Automated RF Probe Measurements

A novel technique has been developed that utilizes the automated RF probe operation as a means to statistically verify and demonstrate the uniformity of a 0.5um ion-implanted MESFET wafer fab at Texas Instruments. Over seventy-thousand MMICs have been characterized in a 6 month span to provide a healthy statistical database. Analysis of the database shows both the GaAs process and automated measurement technology to be robust and yield uniform device performance. Therefore, verifying that RF probe technique generates both cost and cycle time reduction plus quantifies device performance. The incorporation of this technique is consistent with TI¿s ongoing thrust to continually improve its moderate-volume GaAs wafer fab process.