Blows Against the Empire: Lidow's Radical GaN Logic

The co-inventor of the power MOSFET thinks it's possible to make CMOS logic in gallium nitride. If he's successful, everything really does change.

Brian Santo, Senior editor, Test & Measurement / Components, Light Reading

November 30, 2015

3 Min Read
Light Reading logo in a gray background | Light Reading

Efficient Power Conversion (EPC) CEO Alex Lidow tells Light Reading he might be within two years of a breakthrough that would upend the entire semiconductor market: CMOS logic implemented in gallium nitride (GaN).

Lidow has been talking about the end of the silicon era for years. The claim has often been taken as hyperbole because, while GaN has much to recommend it, there was always a catch: the fact that nothing can compete with CMOS logic, and GaN simply can't do CMOS.

On the plus side, GaN has properties that make the performance of GaN power ICs (field-effect transistors, amplifiers, drivers, controllers, etc.) undeniably superior to their silicon counterparts in many circumstances. And silicon simply craps out in several situations, like, for example in high-frequency applications. You have to use GaN, or some other material.

For several reasons, economics favors GaN. This has led to a thriving market for GaN circuitry and components. EPC, Anadigics Inc. (Nasdaq: ANAD), Qorvo Inc. , Macom , Texas Instruments Inc. (NYSE: TXN), Intel Corp. (Nasdaq: INTC) and IBM Corp. (NYSE: IBM) are among the companies making GaN products or exploring the technology. (See Yes, We GaN! New Chips for Cable Networks.)

Silicon's hegemony in memory ICs is also being threatened. This summer, Intel and Micron announced a new memory, said to be 1,000 times faster than extant NAND memory, based on some unidentified "unique material compounds," which is to say, either not silicon or not solely silicon.

Meanwhile, the industry has been pushing silicon closer to its physical limits, to the point that speculation that Moore's Law might one day give out has leaked into even the popular press.

That might happen, but people working with silicon are confident it isn't happening soon. And even if the GaN power ICs and non-silicon memories take over in those markets, that would hardly mean the end of silicon. Again, that's because of CMOS logic, and GaN's inability to do CMOS.

Or so most people think.

Want to know more about the semiconductor industry? Check out our dedicated communications chips content channel here on Light Reading.

Lidow isn't certain himself, but he was confident enough in EPC's prospects to tell Light Reading he'll know within two years whether or not he can implement CMOS logic circuitry in GaN.

Even while expressing uncertainty, he still couldn't help indulging in a bit of bluster, referring to CMOS logic as silicon's Alamo. He knows you know what happened at the Alamo.

If he succeeds, it could indeed mark the beginning of the end of the silicon era. He's cautious about providing too many details, but this is how he explained the challenge:

"Digital chips are CMOS -- complementary MOS, which means they have an electron-dominated transistor, and above it a hole-dominated transistor. They work as a pair; that's where 'complementary' comes from. You have a p-channel device and an n-channel device."

"In gallium nitride, electrons go like greased lightning, and holes don't go anywhere at all. Today, you can't make CMOS logic. You can make NMOS logic."

"But there are several approaches for gallium nitride that look very promising for making these positive charges -- holes -- transport very efficiently on the same chip. If we can overcome that challenge economically -- and I know pretty precisely what it will take -- if we can do it, then CMOS will also be superior in gallium nitride than in silicon, and the entire digital world will start transitioning to gallium nitride."

The ramifications for any application that requires pure speed (e.g., communications networks, data centers, supercomputing) would be profound. GaN is way, way faster than silicon -- theoretically as much as 1,000 times faster.

— Brian Santo, Senior Editor, Components, T&M, Light Reading

About the Author

Brian Santo

Senior editor, Test & Measurement / Components, Light Reading

Santo joined Light Reading on September 14, 2015, with a mission to turn the test & measurement and components sectors upside down and then see what falls out, photograph the debris and then write about it in a manner befitting his vast experience. That experience includes more than nine years at video and broadband industry publication CED, where he was editor-in-chief until May 2015. He previously worked as an analyst at SNL Kagan, as Technology Editor of Cable World and held various editorial roles at Electronic Engineering Times, IEEE Spectrum and Electronic News. Santo has also made and sold bedroom furniture, which is not directly relevant to his role at Light Reading but which has already earned him the nickname 'Cribmaster.'

Subscribe and receive the latest news from the industry.
Join 62,000+ members. Yes it's completely free.

You May Also Like