Technology of passivated surface channel MESFETs with modified gate structures

Surface channel MESFETs have suffered from instabilities and drift in the past. To overcome these effects a suitable device passivation seems to be one of the key aspects. In this investigation such a passivation scheme on the basis of Atomic Layer Deposition (ALD) of Al2O3 has been developed and combined with advanced gate structures, like a field plate and a second MOS gate (in a dual gate configuration).