Cost-effective test, calibration and assembly infrastructure forturnkey integrated pressure sensors

摘要

Even in the customer specific solution domain MEMS manufacturers are facing anrnincreasing request for low cost turnkey products. Fully calibrated sensors with highrnperformance, light weight and small dimension packages are demanded. Considering therncost of a MEMS device the silicon dice constitutes just about one third or less of the totalrncomponent cost. As the silicon fabrication process has already been cost optimised byrnusing batch fabrication, lowering the remaining more than two thirds of the componentrncost in testing, calibration and assembly by fully automation offers the biggest potentialrnto meet the market requirement for cost-effective turnkey solution. This paper presents arncost-effective test, calibration and assembly infrastructure for turnkey integrated pressurernsensors that has been implemented in the fabrication line of the Fraunhofer IMS for thernproduction of barometric pressure sensor. The calibration of the sensors is performed onrnwafer level during the full automated standard electrical circuit test. After dicing therndevices are assembled using automated cassette-to-cassette operation. Choosing arnCLCC8 housing with the outer dimensions of 5 × 5 × 1.7 mm3 results in one of the worldrnsmallest packaged integrated pressure sensor.rnThe presented approach for on wafer level calibration of micromachined pressure sensorsrnhas achieved high accuracy (+/- 1% FSS). The equipment of the assembly line has arncapacity for a throughput of several million sensors per year.