GaAs on insulator (GOI) for low power applications

The widespread use of wireless and mobile communication systems has necessitated the development of high frequency ultra-low power electronics. To minimize power consumption, it is essential to reduce the ungated electron currents in the on-state and the subthreshold leakage current in the off-state. III-V semiconductors are attractive for low power applications because of high electron mobility and saturation velocity. This allows the reduction of the drain supply voltage without sacrificing the current drive, transconductance (g_m ) and high frequency performance. However, the major drawback is the lack of a gate insulator (to allow for MOS technology) and a oxide buffer (to allow for the equivalent of SOI technology). Recently, there has been an increased interest in the wet oxidation of AlAs, mainly for current confinement applications in optical devices. We have developed insulated gate and oxide buffer technologies using the wet oxidation of AlGaAs to provide the insulator. In this paper the fabrication and performance of GaAs MISFET with Al₂O₃ gate insulator, GaAs on insulator MESFET and pHEMT is presented. Also preliminary results using oxidized AlAsSb for the fabrication of oxide buffer AlInAs-GaInAs HEMTs is included