Issue



Whole lotta shakin’ going on


08/01/2008







By Hank Hogan

After the shaking stopped in China on May 12, officials at Intel (Santa Clara, CA) began a familiar drill. The company has a microprocessor test facility in Chengdu, some 50 miles from the epicenter of the powerful quake. According to spokesperson Agnes Kwan, company officials first checked on employees, making sure everyone was all right. They then turned their attention to the buildings and the equipment inside them.

As part of this effort, Intel took immediate action. “As a precaution, we removed the facility from local power and water service until we could do a full assessment,” says Kwan.

In the end, the manufacturing areas at the site turned out not to have sustained damage. The facility was back on line in less than 10 days, notes Kwan.

Sanyo (Osaka, Japan) wasn’t so lucky back in 2004. During that year’s Chuetsu earthquake, the company’s Niigata semiconductor fabrication cleanroom facility suffered extensive damage. Of the five manufacturing lines, one was rendered inoperable and it was months before the buildings were inspected and utilities restored. In the end, says company spokesperson Aaron Fowles, the five lines that had existed at the site prior to the quake were reorganized into two and manufacturing resumed. “In a period of five months, the production levels were back at 70 percent of their original capacity,” he says.

Because of its experience, Sanyo has implemented changes that should help diminish the impact of future earthquakes. These innovations were tested in a 2007 quake in the same region. Fowles says these improvements fall into two categories: one equipment/facilities related and the other involving procedures.

With regard to hardware, changes included fitting gas and chemical dispensing systems to withstand all but the most severe earthquakes. That reduces the chance of hazardous leaks and cuts the time needed to assess damage, since personnel likely won’t have to wait for containment efforts to be complete. Other changes fortified wiring to absorb serious shaking without damage. A third modification added wheels to line machines, mobile shelves, and desks. This allowed them to slide back and forth across the floor without tipping over.

Procedural changes involved reviewing and updating manuals, along with the associated employee training. One result was that the handling of the 2007 earthquake was much smoother than had been the case in 2004. “This aided us in confirming the whereabouts and conditions of all employees within one day, when last time it took up to three days to confirm,” says Fowles.

In some ways what Sanyo did is representative of the industry as a whole. Pat McCluskey, a senior structural engineer with engineering and construction firm CH2M HILL (Denver, CO), notes that the semiconductor industry came of age in earthquake-prone California and is now located in Japan, Taiwan, and China, all of which have their own quake issues. As a result, the industry has had to contend with shaky situations many times and a bit more is learned with each event.

McCluskey notes, for example, that decades ago there was little interest in anchoring things within a building. Today it is standard practice. Also, other improvements are being implemented, ones that avoid the rigidity that can allow more damage to take place. “We’re starting to see the application of systems that don’t just rely on strength. They rely on displacement. They rely on damping. We’ve gone from building a concrete box to trying to build a willow tree,” he says, referring to the flexibility that can save a facility and its internal components and structures.

The reason for this shift is a recognition that movement can’t be stopped and the more rigid something is the stronger it has to be. One idea is to convert movement into heat by, for example, bronze slide plates. These let some slip occur but also transform kinetic energy from movement into heat that is dissipated. Active damping that counteracts incoming disturbances is also becoming more prevalent in vibration-sensitive tools, reports McCluskey.

However, all such efforts fly somewhat in the face of good business continuity planning. What some companies do is have an alternate location they can operate from, explains Gartner research vice president Roberta J. Witty. But fabs are very expensive, so it’s not really feasible to have a spare sitting around ready to take over in the case of a disaster.

“If you’re not going to build out a second site, you really have to pay attention to mitigating as much risk in the existing site as you possibly can,” says Witty.

One way to do so is to have multiple utility feeds and access routes. But the best solution may be the most obvious one, she notes: to avoid the problem entirely by not building in an earthquake zone at all.