High-performance Power PHEMT for Wireless Communications

A low-cost 0.7 ¿m gate power pseudoinorplhic high-electron-mobility transistor (PHEMT) process was developed. PHEMT structure, etch profile and passivation conditions were optimized to yield a device with high breakdown combined with minimal gate lag. A 2 mm PHEMT exhibits dc Idss. of 300 mA/mm, Imax of 500 mA/mm, peak Gm of 360 mS/mm and 3-terminal breakdown voltage of 13 V. At 0.85 GHz such a device exhibits a record output power density of 630 mW/mmn at Vds=5.8 V and 290 mW/mm at Vds=3.4 V with associated PAE of 60%.