TFETs And/Or MOSFETs For Low-Power Design

As discussed in Reducing Subthreshold Swing With TFETs, papers at December’s IEEE Electron Device Meeting examined a variety of potential designs for tunneling transistors (TFETs). That focus continued at the recent CS International Conference. In particular, Nadine Collaert discussed IMEC’s work on InGaAs homo-junction devices. Many compound semiconductor devices depend on heterojunctio... » read more

Power/Performance Bits: Dec. 8

Reducing transistor switching power One of the great challenges in electronics has been to reduce power consumption during transistor switching operation. However, engineers at University of California, Santa Barbara, and Rice University demonstrated a new transistor that switches at only 0.1 volts and reduces power dissipation by over 90% compared to state-of-the-art MOSFETs. "The steepn... » read more

We Must Teach Chips To Feel Pain

By Guido Groeseneken When I was a doctorate student in the 1980s there was lots of wild speculation about Moore’s Law: give it another 10 years and transistors will stop getting smaller, they were saying back then. But in the end, the creativity of engineers turned out to be greater than the pessimism of the forecasters. Yet today I believe that we are close to the end of Moore’s Law.... » read more

What Happened To GaN And SiC?

About five years ago, some chipmakers claimed that traditional silicon-based power MOSFETs had hit the wall, prompting the need for a new power transistor technology. At the time, some thought that two wide-bandgap technologies—gallium nitride (GaN) on silicon and silicon carbide (SiC) MOSFETs—would displace the ubiquitous power MOSFET. In addition, GaN and SiC were supposed to pose a t... » read more

Searching For The Next Power Transistor

For decades, the industry has relied on various power semiconductors to control and convert electrical power in an efficient manner. Power semis are ubiquitous, as they are found in adapters, appliances, cars, elevators, switching power supplies, power grids and other systems. But today’s silicon-based power semiconductor transistor technologies, such as IGBTs, MOSFETs and thyristors, are ... » read more

Moving To Wide Bandgap Chips

The search for new materials to replace CMOS has been in full swing for decades, but in spite of successes in limited niche markets, bulk CMOS remains king. That’s beginning to change, however, as CMOS runs out of steam at advanced process nodes and as the priorities of chipmakers change from pure performance to energy efficiency. And for such applications as automotive electronics for hyb... » read more

New Challenges For Post-Silicon Channel Materials

In order to bring alternative channel materials into the CMOS mainstream, manufacturers need not just individual transistor devices, but fully manufacturable process flows. Work presented at the recent IEEE Electron Device Meeting (Washington, D.C., Dec. 9-11, 2013) showed that substantial work remains to be done on almost all aspects of such a flow. First and most fundamentally, it is diffi... » read more

What’s After CMOS?

Chipmakers continue to scale the CMOS transistor to finer geometries, but the question is for how much longer. The current thinking is that the CMOS transistor could scale at least to the 3nm node in the 2021 timeframe. And then, CMOS could run out of gas, prompting the need for a new switch technology. So what’s after the CMOS-based transistor? Carbon nanotubes and graphene get the most a... » read more

Germanium wedge-FETs pry away misfit dislocations

Any approach to alternative channel integration must consider the lattice mismatch between silicon and other channel materials. Some schemes, such as IMEC’s selective epitaxy, view the lattice mismatch as an obstacle and look for ways to minimize its effects. This point of view certainly has merit: misfit dislocations do significantly degrade transistor performance. Still, back in 2011 Shu-Ha... » read more

What’s After Silicon?

As discussed in the first article in this series, germanium is one of the leading candidates to succeed silicon as the channel material for advanced transistors, and has been for several years. The fundamental challenges of germanium integration were detailed at length in 2007. Unfortunately, knowing what the issues are does not necessarily lead to a solution. When a MOSFET transistor turns ... » read more