Power MOSFETs are basically metal-oxide semiconductor field-effect transistors. For years, power MOSFETs have been used to handle large amounts of power at high speeds and efficiencies with low voltages.
Meanwhile, there has been a lot of hype about GaN over the years, but the technology has failed to live up to its promises. GaN is a material that has attractive wide bandgap characteristics; it tolerates higher voltages than conventional silicon and gallium arsenide (GaAs).
GaN has moved into production as a critical material for LEDs. The bandgap characteristics of GaN also make it attractive for RF, but the technology has been difficult to make in volumes until recent times. Several companies, including Cree, Eudyna, RFMD, and Nitronex, are targeting GaN for LED and RF applications.
Now, the technology could have a new application in power management. For example, today's power supplies take AC power from a wall outlet and convert it to DC. A power supply uses silicon transistors, which, in many cases, suffers from some power loss. One-third of all losses can be attributed to the silicon transistor.
''Power management is a large and growing market that is constantly in need of higher energy efficiency,'' Lidow said. ''Silicon has reached performance limits in power management. Gallium nitride enables a game-changing price/performance ratio.''
Based on the family pedigree, EPC is a company to watch. Lidow's father, Eric Lidow, and his grandfather, Leon Lidow, founded International Rectifier in 1947.
Alex Lidow himself joined IR in 1977. A co-inventor of the HEXFET power MOSFET, Alex Lidow was elected a director and CEO of IR in 1995. He resigned from the position of CEO in October of 2007 after accounting irregularities had been discovered at IR.
Alex Lidow, and EPC, suddenly surfaced in January of 2010, when IR (El Segundo, Calif.) sued its former CEO. According to court documents, Alex Lidow was (and still is) affiliated with Efficient Power Conversion. The court case alleges Alex Lidow stole intellectual property related to GaN power devices. Lidow and his company deny the charges, according to reports.
At about the same time as the suit, IR announced it had started making prototype devices using a proprietary GaN-based power device technology platform. IR's first GaN products, the iP2010 and iP2011, are power stage devices designed for multiphase and point-of-load (POL) applications, including servers, routers, switches and general purpose POL DC-DC converters.
IR's technology, dubbed GaNpowIR, is based on the company's 150-mm GaN-on-silicon epitaxial technology. The technology is based on a depletion-mode GaN HEMT structure, which can be fabricated using standard CMOS production tools.
For years, the industry has been looking at GaN for power management to replace the power MOSFET. The problem is that ''GaN does not always want to grow on silicon,'' said Tim McDonald, vice president of emerging technologies at IR.
This is mainly due to the ''mismatch with the lattice'' with GaN; in additional, there are issues with the thermal co-efficiency of expansion with GaN, he said.
However, IR said it solved the nagging problems with its technology, thereby enabling GaN to move into the power management space.
Like Lidow, McDonald also believes that GaN will eventually replace silicon-based power MOSFETs.
"I think silicon MOSFETs will be around for several years,'' he said. ''But is silicon running out of gas? Yes. GaN will ultimately replace or displace power MOSFETs between 20 Volt to 1,200 Volt applications.''