SOITEC opens Class 1 SOI production facility
John Haystead
BERNIN, France — TO MEET increas- ing worldwide demand for silicon-on-insulator (SOI) substrates, SOITEC (Grenoble, France), has constructed a $50 million manufacturing and headquarters facility in Bernin, France, near Grenoble. The new 10,000-square-meter facility has over 1,500 square meters of Class 1 cleanroom space for producing SOI wafers for 0.18-micron line width ICs. Although the new facility had actually been in limited operation for several months, its official opening ceremony was held in April.
The facility was built by Michelle Ferrier with cleanroom engineering by Faure Engineering (Grenoble, France). Dr. Andre Harve-Auberton, SOITEC president and co-founder, says, “Our two contamination control concerns are the chemical purity of the air, which is a bit stricter for a material supplier than a conventional device production fab, and of our DI water systems. We use a lot of water for cleaning and are concerned about particulate as well as molecular contamination.” Air Liquide (Paris) provides the process gases for the facility.
SOITEC`s thin-film SOI wafers are used in advanced ICs including portable telecommunications systems and notebook computers, which require low voltage and low power consumption. Radiation-hardened circuits, smart power, micro-electromechanical systems (MEMS), mixed signal, high temperature electronics and integrated optics are also targeting the technology.
Initially established to produce wafers using a Simox oxygen-implantation process, SOITEC has shifted its production to Unibond SOI wafers, a thin-film bonding technique using its Smart Cut SOI-implantation process, which the company claims produces wafers with less damage from implants and thermal processing. Most significantly, however, the Smart Cut process requires only one wafer to form a bonded product, allowing SOITEC to produce low-cost, high-volume products using standard semiconductor manufacturing equipment.
Although the facility was constructed for a potential capacity of 700,000 wafers per year, its current rate is around 200,000 eight-inch wafers per year, according to Auberton. “Some production equipment, such as wet benches, are already capable of the 700,000 wafers per year rates, but there are still bottlenecks in implantation and CMP that limit production rates.”
SOITEC has also formed a strategic al liance with Shin-Etsu Handotai (SEH), headquartered in Tokyo, for ad vanced SOI re search and devel – opment, cross licensing, and production. According to Auberton, the most important result of the alliance is that it will provide a reliable second source of Unibond SOI wafers. The two companies are also jointly conducting research into boron, phosphorous and hydrocarbon mo lec ular contamination, and SEH is providing its wafer cleaning technology to SOITEC. Together with SEH, SOITEC expects to reach production levels of over a million eight-inch Unibond wafers per year by the end of 2000. Although the company is not yet producing 300 mm wafers, Auberton notes that, “We demonstrated this capability in December 1997 and believe we will be in significant production of 300 mm wafers in 2001.”