Japanese Engineers Turn High-k Dielectric Transistor Problem on Its Head

One gate metal and two high-k dielectrics could mean cheaper and easier 45-nanometer CMOS process

3 min read

11 December 2007--Computer chips have become so dense that packing even more transistors into them is forcing engineers to break long-standing rules of transistor design. Earlier this year, Intel became the first company to get 45-nanometer chips on the market by finding a way to make a transistor with what's known as a high-k dielectric. To make the transistors work, it had to make the first fundamental change to transistor design in nearly 40 years, switching to metal-gate electrodes from silicon. Intel also had to use a new manufacturing process and two different types of metal to make the transistors. Now a team of engineers at Semiconductor Leading Edge Technologies (Selete), a research consortium for Japanese technology companies, says it has worked out a new way of making high- k dielectric transistors that uses the common manufacturing process and only a single type of metal.

A transistor is basically a switch: When you apply voltage to the gate electrode, it opens or closes a channel in the silicon for charge to flow. In an n -type transistor, electrons flow through the channel, whereas in a p -type transistor, it's actually the absence of electrons (usually referred to as holes) that flows. Transistors in microprocessors are usually arranged so that the two varieties work in a complementary fashion. In these transistors, the gate is separated from the chip surface by a silicon-dioxide insulating layer. As transistors have shrunk down over the decades, the oxide eventually became so thin that it leaked electrons through it, wasting power. Since the mid-1990s, chip makers have been experimenting with replacing the silicon dioxide with high- k dielectrics--materials that can be made physically thick (to stop electron leakage) but electrically thin (so that the transistor turns on easily).

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Are You Ready for Workplace Brain Scanning?

Extracting and using brain data will make workers happier and more productive, backers say

11 min read
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A photo collage showing a man wearing a eeg headset while looking at a computer screen.
Nadia Radic
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Get ready: Neurotechnology is coming to the workplace. Neural sensors are now reliable and affordable enough to support commercial pilot projects that extract productivity-enhancing data from workers’ brains. These projects aren’t confined to specialized workplaces; they’re also happening in offices, factories, farms, and airports. The companies and people behind these neurotech devices are certain that they will improve our lives. But there are serious questions about whether work should be organized around certain functions of the brain, rather than the person as a whole.

To be clear, the kind of neurotech that’s currently available is nowhere close to reading minds. Sensors detect electrical activity across different areas of the brain, and the patterns in that activity can be broadly correlated with different feelings or physiological responses, such as stress, focus, or a reaction to external stimuli. These data can be exploited to make workers more efficient—and, proponents of the technology say, to make them happier. Two of the most interesting innovators in this field are the Israel-based startup InnerEye, which aims to give workers superhuman abilities, and Emotiv, a Silicon Valley neurotech company that’s bringing a brain-tracking wearable to office workers, including those working remotely.

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