Effect of metal electrode edge irregularities on breakdown voltages of AlGaN/GaN HEMTs

Impact of rounded electrode corners on breakdown characteristics of AlGaN/GaN high-electron mobility transistors

“…27) In a previous study, we found that premature breakdown can also be due to metalelectrode irregularities that were randomly formed during the device fabrication, e.g., the liftoff process. 28) It is therefore natural to suppose that a larger active area, as a result of the increased W G , includes a higher number of crystal-related defects and metal-electrode irregularities, increasing the probability of premature device breakdown.…”

“…(2) Premature breakdown is due to crystal-related defects 26) or metal-electrode irregularities that were randomly formed during device fabrication. 28) Henceforth, we refer collectively to these crystal-related defects and metal-electrode irregularities as defective regions. Regardless of the electrode corner shape, increasing the device W G generally increases the active area, which leads to an increased probability that the device includes a defective region causing a decreased V BR .…”