5000+ Wafers of 650 V Highly Reliable GaN HEMTs on Si Substrates: Wafer Breakage and Backside Contamination Results

Abstract

Manufacturing readiness of the world’s first highly reliable 650V GaN HEMT is demonstrated with high process capability (CpK >1.6) for leakage and on resistance. This reliable manufacturing process was developed in a Si-CMOS compatible 6-inch foundry and has been demonstrated with over five thousand wafers worth of data, and spread over four generations of technology nodes. The analysis covers multiple device products and packages collected during industrialization of a JEDEC qualified process over a four year period. Silicon manufacturing processes are employed including a gold-free metallurgy that avoids the use of evaporation/liftoff processes, traditional in compound semiconductors. GaN wafer breakage data from the AFSW Foundry based on four years of manufacturing is presented. Backside contamination acceptance testing results from our foundry is also presented in this paper. These data sets show the flexibility of Transphorm’s GaN Epi and power GaN HEMT process to be compatible to any Si Foundry making the solution scalable. Wide bandgap high frequency and high voltage GaN devices significantly reduce the system size and improve energy efficiency of power conversion in all areas of electricity conversion, ranging from PV inverters to electric vehicles making the above results significant and making GaN high volume production a reality.