Novel dual-gate HEMT utilising multiple split gates

We apply the split-gate structure to dual-gate HEMTs, configured so that a parallel array of channels is defined by split gates that control the effective device width whilst a further continuous gate controls the carrier density within the channels defined by the array. This is a different principle of operation to conventional dual-gate HEMTs. We describe the fabrication of the multiple split gates using a modified T-gate process and present device characteristics.