Notre Dame unveils new high-tech ‘cleanroom’

A new cleanroom unveiled at Notre Dame University will provide researchers with the opportunity to work on cutting edge projects that were previously inconceivable. The cleanroom that was recently unveiled will provide the controlled environment that is required for the construction of integrated circuits and nanotechnology devices.

Campus researchers previously conducted their work in a warren of small laboratory spaces in Fitzpatrick and Cushing halls, none of which met the scientific criteria for pristine research space.

The cleanroom derives its name from the fact that dust and other airborne particles are screened out by a super-filtered air flow system, preventing microscopic particles from entering and disturbing delicate research work. Temperature and humidity are also rigorously controlled.

The filtered air flows in from the ceiling, straight down to the floor, where it is drawn out through ventilation openings. The air then travels upward through channels in the walls to the top air chamber, where it is recycled. Researchers enter the cleanroom through a gowning room, where they don particle-free body suits, shoe and head covers, and eye goggles.

“The biggest contaminate is dust coming in on your shoes or your clothes,” said Patrick Fay, an electrical engineering professor and the cleanroom’s director.

Before stepping into the laboratory space itself, each researcher pauses in an interim space where a burst of air — called an air shower — flows over him or her, carrying away any remaining dust particles.

Similar cleanrooms exist at many other research universities, including Purdue, Michigan and Illinois, but this is the first such ultra-clean space at Notre Dame.

The walls, floor and research stations are designed and built with one goal in mind: to provide no surface that might attract or accumulate stray contaminants. Metal walls are coated with enamel paint; windows have no bottom horizontal lipped edge.

Half of Notre Dame’s cleanroom is Class 100. That means the ventilation system limits airborne residue to no more than 100 particles larger than 0.5 microns per cubic foot. About 40 percent of the space is Class 1,000 — no more than 1,000 particles larger than 0.5 microns per cubic foot. The remaining 10 percent is Class 10,000.

The cleanroom was designed to be reconfigured easily for the constantly changing needs of researchers. “Because this facility was designed from the ground up to support this kind of research, we can do cutting-edge research without a lot of barriers,” Fay said. “If you’ve got a good idea, you can pursue it without redesigning the lab. The infrastructure is there to support it.”

The cleanroom is expected to result in new work Notre Dame researchers previously could only imagine, because they didn’t have the proper space in which to pursue it.

“That’s the whole point of having a cleanroom: to have your wafers — your samples — be pristine,” Fay said.

A wafer is a thin slice of semiconductor used as a base material on which single transistors or integrated-circuit components are formed.

“We can now contemplate making real integrated circuits, or looking at devices where very small levels of contamination are acceptable,” Fay said. In the past, campus scientists had to work around that or avoid it altogether.

Fay’s own research focuses on ultra high-performance electronics: radar communications, signal intelligence and remote sensing. He’s among the professors who previously shied away from doing integrated circuits because they couldn’t get enough of them to work in existing campus research spaces.

Research in the cleanroom isn’t limited to nanotechnology projects. Solar cell development, for example, typically doesn’t involve research at the nano scale, but a solar cell can be rendered useless by a single speck of dust, Fay said.

Students will use the cleanroom, too, such as senior undergraduate engineering majors taking an integrated circuits fabrication elective course.

The cleanroom also will be available to industry researchers. A fee will be charged to help cover the cost of running the facility.

Pilot businesses in nearby Innovation Park or established businesses in the region are among the potential users. Businesses have relocated to some university towns to have access to a high-quality cleanroom.

Fay is among those who see a bright future ahead for Notre Dame’s academic research aspirations because of Stinson-Remick Hall and its cleanroom. “This allows us to move up into thinking about systems integration — integrated circuits instead of single transistors. Those are more visible (in the research world),” he said.

“There’s been really good device-level research going on here for a quite a while. We’re starting to get recognized for that,” he said. “The question is, can we grow that into an even larger footprint, including systems and circuits, and do that in a credible way.”