Texas Instruments Is Buying National Semiconductor

Long time power house in the analog semiconductor area National Semiconductor is being bought by Texas Instruments.

Texas Instruments has announced that it intends to acquire National Semiconductor for $25 per share, or about an 80 percent premium over the $14 and change at which NYSE:NSM was trading at earlier in the day. The combined entity will be a major force in the analog semiconductor market, as TI will add NatSemi's analog business to its own, which was already considerable.

"Our two companies complement each other very well," said Don Macleod, National's chief executive officer, in a statement. "TI has much greater scale in the marketplace, with its larger portfolio of products and its large global sales force. This provides a platform to enhance National's strong and highly profitable analog capability, power management in particular, leading to meaningful growth."

It will be sad to see National go. I have been using their analog power parts such as the LM7805 5 volt regulator since the early 70s. But TI has always had a much better sales and marketing force.

I remember back in '67 when I was first looking into logic ICs (TTL and equivalents) at Raytheon Computer that were destined for an FAA computer. Sylvania had the best parts (SUHL) and TI had the best price. We slowed the computer down 20% and bought car loads of the TI parts.

Nanotubes In Semiconductors

Carbon Nanotubes may be coming soon to a semiconductor near you.

Surrey NanoSystems, a University of Surrey spin-out working on a low-temperature growth process for carbon nanotubes, has secured second round funding of £2.5m

Surrey NanoSystems was established in 2006 as a spin-out from the University of Surrey’s Advanced Technology Institute (ATI) to develop intellectual property which supports the fabrication of carbon nanotubes at low temperature.

The company developed a platform called NanoGrowth which creates conditions for the growth of precision carbon nanotubes at both the temperatures and densities needed for CMOS process technology.

The company is now optimising its technology for the mass-volume manufacturing environment, by scaling the hardware and refining and scaling the materials processing technology.

The new funding will allow Surrey NanoSystems to scale the materials growth technology from its current 100mm wafer size capability to the 300mm sizes used in commercial wafer fabrication plants.

"The semiconductor industry urgently needs a new interconnection technology. If you can solve the problem of growing precision carbon nanotubes at silicon-friendly temperatures - and we have - it opens up a massive potential market," said Ben Jensen, CTO of Surrey NanoSystems.

Yes it does. Right now with large integrated circuits more energy is lost in the connections than in the transistors. Carbon nanotubes are more conductive than the commonly used copper. This should make integrated circuits both faster and cooler. Lower resistance works like that.

It is also possible that things will get even better when carbon nanotube transistor fabrication becomes a manufacturable technique. Faster transistors with lower losses that can operate at higher temperatures. Just what is needed to advance power control technology.

Room Temperature Superconductors One Step Closer

We are one step closer to room temperature superconductors.

Menlo Park, Calif.—Move over, silicon—it may be time to give the Valley a new name. Physicists at the Department of Energy's (DOE) SLAC National Accelerator Laboratory and Stanford University have confirmed the existence of a type of material that could one day provide dramatically faster, more efficient computer chips.

Recently-predicted and much-sought, the material allows electrons on its surface to travel with no loss of energy at room temperatures and can be fabricated using existing semiconductor technologies. Such material could provide a leap in microchip speeds, and even become the bedrock of an entirely new kind of computing industry based on spintronics, the next evolution of electronics.

Physicists Yulin Chen, Zhi-Xun Shen and their colleagues tested the behavior of electrons in the compound bismuth telluride. The results, published online June 11 in Science Express, show a clear signature of what is called a topological insulator, a material that enables the free flow of electrons across its surface with no loss of energy.

Pretty darn exciting. It all depends on something called topological insulation. The article gives some details on how that works. Which gets a bit heavy on the physics. I'm going to skip that here. However, if you have heard of the Pauli exclusion principle it is worth a read.

There are some limitations. For now.

Topological insulators aren't conventional superconductors nor fodder for super-efficient power lines, as they can only carry small currents, but they could pave the way for a paradigm shift in microchip development. "This could lead to new applications of spintronics, or using the electron spin to carry information," Qi said. "Whether or not it can build better wires, I'm optimistic it can lead to new devices, transistors, and spintronics devices."

Fortunately for real-world applications, bismuth telluride is fairly simple to grow and work with. Chen said, "It's a three-dimensional material, so it's easy to fabricate with the current mature semiconductor technology. It's also easy to dope—you can tune the properties relatively easily."

"This is already a very exciting thing," he said, adding that the material "could let us make a device with new operating principles."

Bismuth Telluride is a semiconductor that is currently used for solid state refrigerators. It is also used to generate electricity from small temperature differences. That means the semiconductor industry has more than a little experience in fabricating the material.

If the lab boys have developed a repeatable formula it is possible we might see useful devices using this superconducting property in as little as three years. One use of such properties might be to make a super low noise microwave filter that doesn't require cooling to Liquid Nitrogen temperatures (77° Kelvin). That could be very helpful.

I will be keeping an eye on this one.

If "normal" superconductivity interests you this book is a good place to start:
Introduction to Superconductivity

And if you are a little further along and contemplate building a fusion reactor in your garage, this book could help:
Case Studies in Superconducting Magnets: Design and Operational Issues

Cross Posted at Classical Values

It's Fabulous

In Old Wafers I was discussing how semiconductor fabricating plants that use 150 mm (6 inch) silicon wafers are rather old technology. Over 18 years old. It turns out that that kind of production facility may not yet be obsolete.

A white LED breakthrough at the University of Cambridge could lead to mass production in the UK.

"Its it is a way of making GaN LED die that is a factor of 10 cheaper: growing them on 150mm silicon wafers rather than 50mm sapphire," Professor Colin Humphries told Electronics Weekly.

"The cost of processing a 150mm wafer and a 50mm wafer is the same, or even cheaper in 150mm because a lot of 150mm fabs exist," and raw 150mm silicon wafers are much cheaper to produce than 50mm sapphire wafers.

Everyone would be doing this if it was easy. The critical step is reliably growing GaN/InGaN structures on silicon where the mismatch in lattice constant means wafers bend - preventing lithography - or even break.

This new technology will mean LEDs that cost 1/4 of what they do today. Possibly even less. That would bring LED lights into the cost range of CFLs. Interesting times.

A New Kind Of Transistor

There is some very promising research that promises the development of a new kind of transistor.

A team of Duke University chemists has modified a method for growing long, straight, numerous and well-aligned carbon cylinders only a few atoms thick that paves the way for manufacturing reliable electronic nanocircuits.

The team had already described a method last April for growing the crystals, but the modification is targeted at making a process specifically for producing semiconducting versions of the single-walled carbon nanotubes, sometimes called "buckytubes" because their ends, when closed, take the form of soccer ball-shaped carbon-60 molecules known as buckminsterfullerines, or "buckyballs".

The effort is being led by Jie Liu, Duke's Jerry G. and Patricia Crawford Hubbard professor of chemistry.

"I think it's the holy grail for the field," Liu said. "Every piece is now there, including the control of location, orientation and electronic properties all together. We are positioned to make large numbers of electronic devices such as high-current field-effect transistors and sensors."

A report on their achievement, co-authored by Liu and a team of collaborators from his Duke laboratory and Peking University in China, has just been published in the research journal Nano Letters.

What does this portend? Well quite a few things actually. Carbon Nano Tubes (CNTs) are five times as conductive as copper, electron mobility is about 70 times that of silicon and it should be able to withstand much higher temperatures than silicon without losing its semiconducting properties. Not only that, the material is abundant. So once the manufacturing process is worked out it will mean high power, low loss, extremely high speed transistors.

How soon you ask? First off not all the bugs have been worked out in the laboratory models.

That earlier JACS report described how the researchers coaxed nanotubes to form in long, parallel paths that will not cross each other to impede potential electronic performance. Their method grows the nanotubes on a template made of a continuous and unbroken kind of single quartz crystal used in electronic applications. Copper is also used as a growth promoter.

But that method left one unresolved issue blocking the use of such nanotubes as electronic components. Only some of the resulting nanotubes acted electronically as semiconductors. Others were the electronic equivalent of metals. To work in transistors, the nanotubes must all be semiconducting, Liu said.

The researchers now say they have achieved virtually all-semiconductor growth conditions by making one modification.

In their earlier work they had used the alcohol ethanol in the feeder gas to provide carbon atoms as building blocks for the growing nanotubes. In the new work, they describe how they tried various ratios of two alcohols—ethanol and methanol—combined with two other gases they also used previously—argon and hydrogen.

"We found that by using the right combination of the two alcohols with the argon and hydrogen we could grow exclusively semiconducting nanotubes," Liu said. "It was like operating a tuning knob." The inert argon gas was used to provide a steady feed of the ethanol and methanol, with hydrogen to keep the copper catalyst from oxidizing.

After making the nanotubes by chemical vapor deposition in a small furnace set to a temperature of 900°C, the researchers assembled some of them into field-effect transistors to test their electronic properties.

"We have estimated from these measurements that the samples consisted of 95 to 98 percent semiconducting nanotubes," the researchers reported.

Now that is probably good enough for first generation transistors in some applications if those kind of numbers can be achieved in production. However what you want for general use is 99.9% or 99.99% semiconducting CNTs. The more nines the better. So how soon? I'd say pilot production in five years, and full scale production (10s of millions of devices) in about eight years. Fortunately it builds on the base of silicon semiconductor production so the equipment needed is likely to be very similar to what is already in use.

The best power conversion equipment we have using silicon has efficiencies topping out at around 95% with the more typical units running at 85% to 90% efficiency. With these new devices we could reach 99% or better. They could also mean 20 times faster computers that use 1/10th as much power as current devices. Considering that we already have chips on the market that deliver 25,000 MIPS for 360 milliwatts that would be something. It would be roughly equivalent to 1,000 Cray 1s in your pocket that could be powered from an AA cell for a month. Cell phones could run for weeks on a charge. Laptops that could run for many days. Faster please.

Cross Posted at Classical Values