[22a-E302-1~12] 13.7 Compound and power devices, process technology and characterization

△ [22a-E302-6] Contact resistance improvement and modeling of stripe-recessed ohmic contact for InAlGaN/AlN/GaN HEMTs

〇Yusuke Kumazaki¹, Shiro Ozaki¹, Naoya Okamoto¹, Naoki Hara¹, Toshihiro Ohki¹ (1.Fujitsu)

Keywords:GaN, HEMT, ohmic contact

In this work, stripe-recessed ohmic contact for InAlGaN/AlN/GaN HEMTs were developed. This technique introduced periodic multi-fin structures on ohmic electrodes through low damage patterned recess etching and metallization with low temperature annealing (600℃). The increase of fin density led to the reduction of contact resistance, indicating that metal/channel direct contact acted as low-resistive current pass. Under the high off-stress conditions, the device with stripe-recessed ohmic contact showed the highest drain current at knee voltage compared to the devices with other ohmic techniques. It is evident that InAlGaN/AlN/GaN HEMTs with stripe-recessed ohmic contact is one of the best techniques to achieve low contact resistance with low-thermal-budget processes.