原创 A look at TI's RFAB

A week ago, representatives from Texas Instruments (TI) asked a few members of the media to visit Richardson, Texas. It is for a tour of RFAB—the semiconductor industry's first 300-mm analog fab and first LEED certified fab.

TI originally broke ground on the shell for RFAB in 2004. Work was completed by 2007, but the shell sat idle for more than two years until TI happened on a sweetheart of a deal—scooping up a boatload of 300-mm production equipment from bankrupt memory chip vendor Qimonda AG for the deeply discounted rate of $172.5 million.

According to Paul James Fego, vice president of worldwide manufacturing for TI's Technology and Manufacturing group, RFAB would have been a 200-mm analog fab—if not for the deal that was available on the Qimonda equipment. "We had the building built, we had an equipment opportunity," he said. "And we knew the breadth and the volume of our analog business could fill a 300-mm fab."

TI's 1.1-million square foot RFAB includes about 250,000 square feet of cleanroom space.

Ramping toward full production

The area of RFAB nearest the observation window includes more than a dozen process tools, including ion implantation systems made by Axcelis Inc. and Varian Semiconductor Equipment Associates Inc. Source: TI.

Within weeks of the September 2009 announcement that TI planned to open the first 300-mm analog fab, the Qimonda equipment began arriving in Richardson, just a few miles north of TI's headquarters and a cluster of TI fabs in Dallas. Tom Weichel, manager of RFAB. (Weichel said even the furniture in RFAB's office space came from Qimonda).

RFAB started ramping toward full production at the end of last year. The facility, which includes about 250,000 square feet of cleanroom space, is currently running about 350 wafers per day, ramping to between 600 and 700 wafers per day by the end of 2011, according to a TI spokesperson.

Analog requirements

RFAB's automated overhead transport system (top) is used to transport wafers packed in front-opening unified pods to all tools in the fab. The overhead transport system, made by Japan's Muratec Automation Co. Ltd., was broken down at Qimonda's fab in Virginia, transported to Richardson, and then installed at RFAB. Source: TI.

In addition to the equipment purchased from Qimonda in Virginia, RFAB also includes other 300-mm tools acquired from Qimonda in Dresden, Germany, as well as few other used tools acquired from other sources to support analog production, Weichel said. "An analog process is a little bit different than digital," requiring additional tools, Weichel said.

TI initially announced it would begin hiring 250 workers for RFAB in September 2009. Weichel said the company is hiring. Asked how many employees the fab currently has, Weichel would only say that "many hundreds" of people, including contractors and TI personnel, are on site on any given day.

More tools

RFAB has, in total, well over 100 separate process tools. Source: TI.

RFAB is the first chip fab to achieve LEED Gold certification from the U.S. Green Building Council, attesting to the "greenness" of the site and building. To achieve this certification, TI had to meet sustainability, water efficiency, energy, atmosphere, recycling and indoor environmental quality standards. Environmentally friendly features of the site include a compost-based fence for stopping silt runoff, a rainwater storage pond, a 2.7-million gallon reservoir to prevent water runoff, and reflective concrete to mitigate the urban island heat effect. Inside RFAB's office space, green touches include waterless urinals in restrooms, passive solar orientation, smart lighting with motion sensors, solar water heating and many others.

Weichel acknowledged that the LEED certificiation applies only to the facility, not the semiconductor manufacturing process that goes on inside. But he said part of TI's mandate is to reuse chemicals where possible and keep the presence of potentially harmful substances to a minimum.

Asked about the reconciliation between the "green" fab and the requirement of using toxic chemicals in the semiconductor manufacturing process, Weichel said: "Our focus would be first to always choose something safe [where possible]. Then, if we have to use something [toxic], we reuse it as much as we can."

Dylan McGrath

EE Times