Monolithic integration of GaN gate driver and power transistor switching functions

Using Gallium Nitride semiconductors to improve power systems and conversion efficiency by up to 5% 

High voltage and high switching speed DC-DC converters based on Gallium Nitride (GaN) technology offer a revolutionary breakthrough for the next generation of power systems. Moving from Silicon (Si) to GaN, will mean power-conditioning subsystems with better efficiency and reduced mass/volume (50%). GaN transistors also offer the inherent ability to operate at higher voltages than Si and with improved radiation tolerance. All of these attributes are important for space application. The application of this technology is useful for any missions requiring highly miniaturised power conversion subsystems with improved efficiency.At present, the externally connected gate driver topologies (e.g. Using bond wires, long PCB tracks) limit the useable switching frequency due to gate loop parasitics.A GaN die comprising of a half-bridge topology, i.e. Using 2 serial FET, meant to play respectively the role of switching and rectification in many space applicable power conversion topologies is needed. The die will also contain the gate driver circuit for each FET. Such drivers are inherent to the interface between digital control signal and FET gate to source voltage. They must cope with source voltage floating with respect to control voltage.;This activity encompasses the following tasks: Establish technical requirements of design ;Process trials to allow monolithic integration. To include: Logic Inverter Protection circuitry On chip passive components ;Compatibility of interconnection metallisation between low power logic and high power switching functions Building block functions shall be designed, simulated and characterised as separate entities Manufacture and test ;Die used within a selected power switching converter to practically demonstrate the benefit of the monolithically integrated solution.