To help gallium nitride (GaN) technology manifest itself to its true potential, researchers at HRL Laboratories demonstrated GaN CMOS field-effect-transistor (FET) technology, establishing that GaN can become the technology of choice for power conversion circuits that are made in silicon today.
Today, GaN transistors are being designed into radar systems, cellular base stations and power converters like those found in computer notebook power adaptors. GaN CMOS IC applications could include power integrated circuits that are more energy-efficient, have significantly smaller form factor and lower cost and can operate in harsh environments. In the long term, GaN CMOS has the potential to replace silicon CMOS in a wide range of products.
GaN transistors have long excelled in both power switching and microwave/millimeter wave applications, but their potential for integrated power conversion has been unrealized. “Unless the fast-switching GaN power transistor is intentionally slowed down in power circuits, chip-to-chip parasitic inductance causes voltage instabilities”, according to HRL researchers.
The researchers say that they have overcome that limitation by developing a GaN CMOS technology that integrates enhancement-mode GaN NMOS and PMOS on the same wafer. Integration of power switches and their driving circuitry on the same chip is the ultimate approach to minimizing the parasitic inductance.
Earlier, GaN CMOS IC was considered difficult or impossible, due to the challenge in making P-channel transistor and integrating an N-channel transistor. The recent work has opened up the possibility of making GaN CMOS IC’s.