IBM to adopt SIMOX material

10/01/1998

IBM to adopt SIMOX material

In a move that boosts both silicon-on-insulator technology in general, and the SIMOX method of SOI formation in particular, IBM Microelectronics will start volume production of high-speed logic devices on SIMOX substrates next year.

Initial usage in 1999 will be on proprietary chips for IBM servers, minis, and mainframes; this will be followed by use in parts for the merchant market and foundry customers.

The disclosure was a boost to Ibis Technology, developer of oxygen implanters for SIMOX production and a supplier of SIMOX wafers. While IBM will not say who is providing its tooling, Ibis, Danvers, MA, has reportedly sold three implanters to IBM for use in development at its East Fishkill, NY, facility.

John Kelly, IBM VP of server development, said "several more" machines would be needed to accommodate a planned production ramp at the Burlington, VT, line. Mike Alles, director of marketing and applications engineering at Ibis, said about 20 wafers/day/machine could be produced using a full-dose, 3500 ? buried layer SIMOX process. While IBM plans to make its own SIMOX wafers initially, Kelly said other options would be considered as volumes increase; the SIMOX process currently adds about 10% to wafer costs, but plans are in the works for reduction, he added.

Officials at Ibis and competitor Soitec have for a number of years touted SIMOX as the best path to SOI, as it can be implemented in a continuous flow process using familiar technologies like implantation and post-implant thermal processing. Until now, usage has been confined to niche markets such as radiation-hardened circuits. Kelly called SIMOX "by far the best" method that had been evaluated by IBM.

Kelly said IBM has been able to produce SIMOX wafers with defect densities equal to bulk silicon. The company reportedly has very advanced SOI device models and well-developed EDA tools to implement the models in IC designs. Kelly said these tools would be made available to IBM ASIC customers, but not sold or licensed.

Additional good news for SIMOX may be in the offing at Motorola. Jim Pendergast, director of Motorola`s Wireless Research & Development Lab, said his firm plans to bring SOI into production "when it gives a clear advantage to our customers both in terms of performance and cost." He added, "Our focus is on SIMOX; we`ve been working with Ibis. But we`ve also had a fairly long research program looking at bonded wafers."

IBM`s recent announcement of its silicon-on-insulator plans has prompted a number of current SOI users to point out (respectfully, of course) that they`ve been in the game for a while now. At Allied Signal Microelectronics, for example, marketing director Phil Davies notes that his firm`s Columbia, MD, fab has shipped SOI devices for five years into merchant and captive markets; these include the Iridium telephone satellites as well as high-temperature applications inside jet engines and on oil-drilling rigs. Meanwhile, Peregrine Semiconductor, San Diego, CA, noted that it began commercial shipment of silicon-on-sapphire devices in June of last year, and will upgrade its existing 1100 MHz RF device to 1900 MHz in the spring of 1999. - P.N.D.