Metamorphic HEMT 0.5 /spl mu/m low cost high performance process on 4" GaAs substrates

Fabrication, performance and uniformity of 0.5 /spl mu/m gate length, passivated InAlAs/InGaAs metamorphic HEMTs (MHEMT) on 4 inch GaAs substrates are reported. Excellent uniformity of DC and HF characteristics across 4" wafers was achieved. An f/sub T/ of 53 GHz and an f/sub max/ of 200 GHz was obtained for 0.5 /spl mu/m gate length devices. The standard deviation of the threshold voltage is 23 to 35 mV from wafer to wafer. These results demonstrate the potential of a low cost technology to fabricate MHEMTs on 4" GaAs substrates using i-line steppers to manufacture in production volumes.