Low temperature (LT) GaAs MISFETs with 680 mA/mm drain current and 28V
drain voltage have been fabricated. This represents the highest I-V p
roduct of a GaAs FET to date, indicating an RF-power handling capabili
ty of 2.1 W/mm. The weak dependence of the breakdown voltage on the do
ping-thickness product indicates that further improvements are possibl
e.