Improvement in GaAs MESFET drain conductance by a steplike-gate structure

A new steplike-gate GaAs MESFET structure, having a low drain conductance in comparison with a conventional recess structure, is presented. In order to reduce the drain conductance, the device design parameters related to gate structures are optimized using a two-dimensional device simulator. Experimental results obtained from fabricated devices, based on these optimized device parameters, show excellent low drain conductance characteristics. The reduced drain conductance can improve the maximum available gain in high-frequency GaAs analog integrated circuits.