NORTH TYNESIDE, ENGLANDTwo years after shutting its doors, a semiconductor wafer facility is being reborn. The one-time Siemens AG (Munich, Germany) plant is being purchased in a complicated deal by the Atmel Corp. (San Jose, CA). Key to the multi-billion dollar agreement is 65,000 square feet of cleanroom space, still pristine after being mothballed for years.
“We don't want to walk into a shell of anything. The cleanroom's obviously important,” says Donald Colvin, Atmel's chief financial officer.
Atmel is taking over the facility for an undisclosed sum. At the same time, Atmel and Siemens are entering into an arrangement where Siemens will buy $1.5 billion worth of Atmel products over the next four years.
Atmel's specialty is non-volatile memory chips, which are in short supply and are widely used in such products as cell phones. Also part of the financial mix was a nearly $40-million grant to Atmel from the British government because the plant will boost regional employment.
An aerial view of the North Tyneside site. When the cleanroom is back up and running, Atmel could put close to 1,100 people back to work.
Atmel has stated it will install CMOS, BiCMOS and Silicon Germanium process technology in the new fab and will eventually manufacture 0.18-micron 200-mm wafers for non-volatile memory and microcontroller products. Because Atmel is purchasing an existing cleanroom, the company saves the nine months or so it would have taken to construct a new facility. According to Colvin, “We [Atmel] can probably start production in the second quarter next year,” he says.
Atmel will not say what production levels of the rejuvenated facility will be.
In it's first incarnation, the 6,000-square-meter (65,000-square-foot) cleanroom was spread over two buildings in a Class 1 minienvironment approach, complete with SMIF boxes and the latest equipment. At the time of shut down, the fab was producing 16-megabit DRAMs using a 0.35-micron process, with plans to go to 64-megabit DRAM manufacturing at 0.25 micron.
However, memory prices dropped 95 percent between Siemens' decision in 1995 to invest in the plant and the 1998 decision to shut it down. Also in 1998, a customer canceled a key contract that would have consumed half the plant's 20,000 200-mm wafer capacity. Siemens cited these factors in closing the plant, which had been opened in a ceremony attended by Queen Elizabeth II only a year before and in which Siemens had reportedly invested more than $700 million.
Closing the plant resulted in the loss of 1,100 jobs, and Siemens had to repay a government grant, said to be $70 million.
Siemens had experience mothballing a cleanroom. According to Gerhard Tegtmeyer, a member of Siemens Industrial Building Consultants group, the mothballing was such that the cleanroom could be restarted and ready for equipment in less than six months.
Siemens personnel purged gas lines, cleaned out chemical piping and disconnected equipment in an orderly and meticulous fashion. Siemens shut down one of the plant's two water treatment systems completely and operated the second at reduced capacity. Air handling was likewise cut back without sacrificing cleanliness.
“In each building always one of the fresh air make-up units was in operation, in rotating sequence to assure that all units were maintained properly,” notes Tegtmeyer.
The cost for this is unclear because Siemens' semiconductor operations were revamped at the same time. In August 1999 Siemens spun off its semiconductor operations into Infineon Technologies AG.
While the cleanroom is part of the deal, the manufacturing equipment is not. Atmel's Colvin says, “Of the original DRAM equipment, 90 percent is not of interest to us.”