Tucson tech: Startup sees role in next-gen 3-D chips

This photo shows a microscopic image of a thin glass interposer used in a new generation of stacked "3-D" integrated circuits, made by Triton.

The future of electronics may be up, instead of out. And that's a good direction for a local company vying to be part of perhaps the next big thing in electronics: so-called 3-D circuit design.

Last week, local tech startup nMode Solutions announced that it had teamed up with Tokyo-based Asahi Glass Co. Ltd. and invested $2.1 million to co-found a subsidiary business, Triton Micro Technologies.

The new company will develop technology to form connections, called interposers, through thin glass to help drive a new generation of vertically stacked, 2.5-D and 3-D semiconductor chips and integrated circuits (think "three-dimensional").

Interposers allow the creation of a high number of electrical connections between a silicon chip and a printed circuit board - a key to new space-saving, stacked semiconductor designs, the companies say.

A few companies already are making memory and other integrated circuits with 3-D technology, and Intel Corp. has developed 3-D transistors for some of its Core series of central-processor chips.

Stacked, 3-D designs offer a way to pack more processing power into a smaller package - a key driver of technology and even more vital in today's world of smartphones and tablets, said Tim Mobley, CEO of Triton and nMode.

"You can basically put new capability into the same area," said Mobley, who founded nMode in 2010 after spending three years working as an electrical engineer at Tucson-based Raytheon Missile Systems.

The 3-D designs also can save a lot of power because signal pathways are shorter. (So-called 2.5-D designs involve integration of circuits in more of a side-by-side architecture, but they share some of the same advantages of 3-D designs.)

Mobley, who prior to working at Raytheon spent a decade as a design engineer at chemicals giant DuPont, felt it was time to pursue his passion for circuit design on his own, even as 3-D chips started to emerge.

"It was something that was just a calling, I guess," Mobley said.

nMode launched successfully in 2010 as a tenant at the Arizona Center for Innovation, a high-tech business incubator at the University of Arizona Science and Technology Park.

nMode has built a clientele in advanced circuit design including automotive electronics supplier Bosch, as well as offering custom circuit substrate material and glass interposers.

The company wanted to refine and pursue its glass interposer technology, and it found an eager partner in Asahi Glass, Mobley said.

Asahi - part of the Mitsubishi group of Japanese industrial giants - is one of the world's biggest makers of high-tech glass for displays. Asahi, Corning and other major technical glass companies are looking to extend their reach beyond displays, Mobley said.

While most of the companies pursuing 3-D designs are using silicon as their interposer material, Triton is focused on glass.

Glass is much cheaper than silicon and can be used the same way as an interposer material, Mobley said.

"The cost difference is significant," Mobley said.

""When you get to that level, you don't need silicon. It's overkill."

The transparency of glass is also a plus for certain applications, such as biometric fingerprint sensors, he said.

But glass is a tricky material to work with.

"We needed to put a hole in glass, which turns out not to be that easy," Mobley said.

With Asahi's help, Triton has developed a process of drilling holes in thin glass with lasers and filling those holes, known as vias, with conductive material like copper for eventual circuit connections.

The company can make custom glass interposers in standard silicon wafer sizes. Those layers are then mated up to wafers and "diced" along with other layers into individual chips.

An electronics industry consultant said Triton's offering should find some takers.

"The most exciting part of this is, there are a lot of people who are very interested in looking at a glass interposer for various applications," said Jan Vardaman, president and founder of Austin-based TechSearch International Inc. "But they haven't found a place to purchase those, so I think it's a great first step in that direction."

Triton may have a tough time making inroads among major semiconductor fabricators, or foundries, Vardaman said.

But glass interposers offer an exciting new option for many applications, said Vardaman, who estimated the market for such products could reach tens of millions of dollars by 2016.

Up to now, work with glass interposers has been "more R&D-type projects, university research, so this is a very good commercial step, and I expect they'll be getting a lot of calls," Vardaman said.

The company uses labs at the UA's Micro/Nano Fabrication Center for research and has headquarters with nMode at 1840 E. River Road. Mobley said Triton could quickly ramp up to produce 6,000 to 8,000 wafer-sized interposers per month.

Mobley, who studied for an MBA at the University of Pennsylvania's Wharton School, said the potential cost savings of the glass interposers have already attracted interest of some major companies.

"It's forcing them to look at this. It's so attractive," he said.

Contact Assistant Business Editor David Wichner at dwichner@azstarnet.com or 573-4181.

Senior reporter covering business and technology for the Arizona Daily Star/Tucson.com