Sematechs Burgeoning patents may be future revenue generator

01/01/1997

Sematech`s burgeoning patentsmay be future revenue generator

Peter N. Dunn, Senior News Editor

With the recent awarding of a patent on pulsed-force chemical-mechanical planarization, SEMATECH now has a portfolio of some 70 patents. Though its primary objective is protecting the usage rights of member companies, the consortium may be nearing a time when it can begin to derive revenue from its intellectual property holdings.

The CMP patent, awarded to SEMATECH employee Scott Runnels and intern L. Michael Eyman, covers a planarization tool in which the down force on the polishing pad is varied between minimum and maximum values. When force is at a minimum, slurry flows into the space between pad and wafer; when the force is increased, the slurry is forced out, allowing the abrasive pad to erode wafer surface features.

The application claims that pulsed force will improve control of the CMP process, and has the potential for increasing yield and reducing manufacturing costs.

Like many of the SEMATECH patents, this one involves an easily implemented improvement to an existing process. In addition, the technology is in one of a handful of "key areas, where we can provide significant advances," noted Bob Falstad, general counsel and secretary of the Austin, TX, consortium. CMP and phase-shift photomasks are two prime examples of these focus areas.

Falstad explained that SEMATECH has three types of patents: those awarded to SEMATECH`s own employees, those awarded to member company assignees working at SEMATECH, and those awarded to university researchers as part of work sponsored by SEMATECH or its Centers of Excellence program. "Generally, ownership follows inventorship - if a member company assignee invents it, it`s owned by the member company. But there are fairly extensive licensing privileges," Falstad said.

Under SEMATECH rules, all member companies get a royalty-free license to use the patents. Member firms can license their patents, but not to the exclusion of other member companies. Although it has not happened yet, SEMATECH-owned patents can be licensed to nonmembers with board of directors approval.

"If the opportunity presents itself, we would take advantage of that," said Falstad. "We haven`t squarely faced up to it yet, but the portfolio is starting to build fairly rapidly. Until now we`ve been using them defensively, to ensure that we`re not precluded from using technology we develop or sponsor, but we can also use them to generate revenue through licensing, or obtain an injunction against someone. To date, it`s been only defensive."

Revenue would probably be relatively modest, compared to some corporations, but Falstad said the group intends to continue building the portfolio (see table). "One reason Texas Instruments has been able to be aggressive [in generating licensing revenue] is that in the `70s and early `80s they stuck to their knitting and continued to file applications on technology development," despite a legal climate in which infringement verdicts were less common than in the later `80s and `90s, commented Falstad.

Barbara Holliday, SEMATECH`s intellectual property administrator, said the consortium averages about 15 patent filings/year. This year, about 30 inventions have been disclosed by researchers, and about one-third of them have gone into the patent filing process; disclosures peaked in 1994 at 72.

When deciding whether to file, "We look at the relevance to our existing patent portfolio, the return on investment possibilities, the extent to which it can be implemented, and the extent to which use can be detected," said Falstad.

SEMATECH`s patents cover such areas as circuit design features, process techniques, and monitoring and control systems.

One interesting award, given to Scott Shackleton, et al., in 1994, covers the so-called "Silo Fab," a structure that integrates cleanrooms and wafer conveyors into a multilevel cylinder (see figure). All processing takes place within the cylinder`s interior, in areas that personnel never need enter; the central core, or "silo," is a nitrogen-purged area in which wafers in progress can be stored and transported. Sealed passage ports allow for transfer of the wafers in and out of the inner area where processing takes place. The radial walls on each level of the fab are moveable, allowing for re-arrangement of tooling and a modular approach to fab layout. This design would allow addition or removal of cleanrooms without a complete fab shutdown.

Diagram of the "Silo Fab," which is part of the SEMATECH patent portfolio. The building could be constructed either above or below ground.