DC and microwave properties of 0.5 /spl mu/m AlGaN/GaN high electron mobility transistors fabricated on 2-inch process line

DC and RF characteristics of AlGaN/GaN HEMTs processed by 2-inch stepper lithography are presented. The devices, grown by MOVPE on 2" sapphire wafers consist of: GaN buffer, Al/sub 0.25/Ga/sub 0.75/N spacer, doped Al/sub 0.25/Ga/sub 0.75/N supply layer, Al/sub 0.25/Ga/sub 0.75/N barrier, GaN cap. Refractory source and gate contacts along with mesa isolation and air bridge technology are applied. Typical values for maximum saturation current, transconductance and pinch-off voltage are: 616 m/A/mm, 203 mS/mm, -3.5 V with very good homogeneity across 2". The cut off frequencies f/sub T/ and f/sub max/ are 24 and 54 GHz respectively. A standard small signal equivalent circuit model exactly describes DC- and microwave properties.