150 GHz FMAX with high drain breakdown voltage immunity by multi gate oxide dual work-function (MGO-DWF)-MO SFET

We propose Multi Gate Oxide — Dual Work-Function (MGO-DWF)-MOSFET which is suitable for low power AB-class RF power amplifier (RF PA). This was examined for the first time by comparing with a standard Cascode connection circuitry composed of LV- and HV- MOSFETs. Dramatically improved FMAX (150 GHz) with sufficient drain break-down voltage (VBD) was experimentally confirmed in a practical device structure. MGO-DWF-MOSFET has multiple roles in a unit device such as LV-MOSFET in source side regions and HV-MOSFET in drain side regions. This distinctive structure enables the reduction of the device area and a gate capacitance (CG) with a higher transconductance (Gm) and the suppression of drain conductance (GDS). Enhancement of FMAX, in other words, DC operation current reduction is achieved at a given operation point. This indicates that MGO-DWF MOSFET is advantageous for low power amplifier circuitry applications, typically for RF PA in internet of things (IoT) products.