Touring the Solid State Electronics Laboratory is like being in a submarine — pipes and tubes line narrow, dimly lit halls, and the monotony of cinderblock walls is broken occasionally by consoles bristling with meters and valves, strobe lights ready to flash out warnings should something go wrong.
The hallways pass large racks of buzzing metal and wire and a constant hum resonates from the floor.
Sandrine Martin pauses while navigating the SSEL’s corridors to point to a room emitting a pale yellow glow. “That’s our most expensive piece of equipment,” says Martin, an adjunct electrical engineering and computer science professor. Inside is a large rectangular box that looks like a stainless steel refrigerator on its side, only with more doors. It’s called an electron-beam lithographer, and it costs $1 million.
The point of it all: to produce as little as possible. That’s the mantra of the fields of micro- and nanotechnology, which are at the center of research in the North Campus lab. Micro- and nanotechnology deal with the manipulation of substances at extremely small scales to make tiny mechanisms and electronics. The difference between micro- and nanotechnology lies solely in scale: Nanotechnology is more minuscule extension of microtechnology.
Less is more for the scientists who continually push for smaller structures and finer detail. And today, “less” is tinier than ever before: “micro” refers to the micron, a unit of length that is a millionth of a meter (a human hair is 15 microns in diameter). A nanometer is a thousandth of a micron or one billionth of a meter.
“When you go down to these levels, you are at the same scales as the distance between two atoms or a molecule,” Martin said.
But Martin and her colleagues’ obsession with ever shrinking-technology begs the question: What’s the point?
Khalil Najafi, an electrical engineering and computer science professor and director of the SSEL, smiled when asked the question.
“Well, that will take a long time to answer.”
Every aspect of modern life and many scientific fields, such as biotechnology, could potentially be impacted by nanotechnology, Najafi said.
“Because it deals with the smallest elements of many objects, nanotechnology will have a profound impact on everything from the materials we use in our daily lives, such as coatings to protect fabric, to many new drugs being developed that require (nanotechnology) to amplify their effectiveness and reduce their side effects,” he said. Using nanotechnology, researchers can gain insight into the chemical makeup of these fabrics and drugs and manipulate them to increase their efficiency.
This same technology could offer doctors new ways to monitor their patients’ vital signs through tiny implanted machines, Martin said. “These devices can go through the skin or use the blood system as channels and circulate in the body,” she said. Once there, they can be used to check up on a patient or administer specifically targeted drugs.
Nanotechnology could also aid environmental scientists in developing strategies to combat pollution. “Pollution is caused — in one form or another — by nano-sized particles, and understanding how these particles are generated and interact with one another and the atmosphere will help us to either prevent or mitigate problems that come up,” Najafi said.
But nanotechnology isn’t just part of a distant future where tiny robots scrub the air. In fact, nanotechnology is already ubiquitous in today’s world. You just might not be able to see it — and that’s the point.
Advances in micro- and nanotechnology, for instance, are responsible for the small-and-getting-smaller size of many electronics.
“Already, many electronic products from computers to … music players and cameras incorporate what we call ‘nanotechnology-enabled’ devices,” Najafi said. “Computer chips are made of transistors that are about 100 nanometers large and can therefore contain hundreds of millions of transistors in an area smaller than a postage stamp.”
Nanotechnology has also been put to practical use outside the electronics industry; companies have used nanotechnology to develop stain-resistant pants and flexible tennis racquets with the strength of steel. These materials were made using many techniques perfected in nanotechnology labs like the SSEL.
And as nano- and microtechnology advance, the fields to which they can be applied continue to expand.
Micro-electro-mechanical systems is one area of research being explored at the SSEL that could have a wide-reaching impact. MES aims to build complex gear systems, motors and valves at the micron level. These components can then be assembled to make fully functioning microsystems.
Najafi is working on integrating MES with wireless technology to develop tiny sensors with a broad range of applications.
These sensors could be applied to fields not normally associated with microtechnology, such as environmental science and homeland security. For example, Najafi and his colleagues are attempting to shrink a collection of large lab instruments into a “wristwatch laboratory” that could monitor airborne biological threats or pollution — all powered by a watch battery. This portable lab could offer near-instantaneous results in a convenient package.
As the field of microtechnology expands, nanotechnology is sure to follow, Martin said.
The broadening of the nanotechnology field should offer benefits to many more scientists, but it introduces new challenges for researchers and labs like the SSEL, Martin said.
More scientists interested in nanotechnology leads to more scientists coming to labs like the SSEL — scientists who may or may not be familiar with the delicate machinery used and complex protocols followed at the lab.
And protocols and delicacy are of the utmost importance when working at the nanometer level. As the scale of this work shrinks, the number of precautions taken to ensure a clean working environment and functioning equipment grows in proportion.
“At these small scales, a thing of dust is huge,” Martin said. “This is a problem when you’re doing micro- and nanoelectronics: A dirt particle on a circuit can ruin it.”
So the SSEL keeps its equipment in sterile “clean rooms” bathed in yellow light to protect it from damaging ultraviolet rays. Researchers are swaddled in blue coveralls and surgical masks so that only their eyes show — and those are encased in safety goggles to contain errant eyelashes. Ventilators roar as they furiously circulate air to prevent dust buildup, changing the air in the room as many as 500 times an hour. A normal office building usually has one air change per hour.
But despite these precautions, problems with the equipment abound.
“It’s really what you could call bad equipment,” Martin said. “It’s very expensive to buy, expensive to install, expensive to maintain, and it breaks down often.” Even a 75 percent rate of operation is considered a boon, she said.
The difficulty and cost of maintaining the equipment needed for nanotechnology research means that only a select number of universities and companies can have extensive facilities like the SSEL. As a result, scientists looking to work on nanotechnology often have to travel a substantial distance to such labs.
The lab has hosted people from all over the United States, and local companies regularly use the facility, Martin said. And this is where the inexperience and lack of knowledge is most often felt.
“We had people coming in who weren’t familiar with nanotechnology and didn’t know how to use the equipment,” Martin said. When searching for help with the facilities, it was often hit-or-miss, with no structured training program in place.
But starting this year, the SSEL is a member of the National Nanotechnology Infrastructure Network, and Martin thinks things are changing for the better. NNIN is a nationwide network of 13 nanotechnology facilities, sponsored by the National Science Foundation, charged with increasing accessibility to the field through greater training and outreach.
Earlier this year, the SSEL was named as part of the network following a nationwide competition. As an NNIN facility, the SSEL receives $1.2 million annually, which is used primarily to hire and pay new staff.
The staff was hired partially to accommodate a potential increase in new users, as one of the goals of NNIN is to get more people outside of the field involved with nanotechnology research.
Najafi, who along with his colleague EECS Prof. Fred Terry is responsible for bringing the NNIN to Michigan, is excited about the ability to reach out to other fields that NNIN provides.
“More and more people are saying, ‘If only I could do that (using nanotechnology),’ ” he said. “Now we can have professional staff to help them get in the lab and do it.”
Martin, who is the new NNIN technical manager, said the SSEL’s status as a hub for nanotechnology research should help everyone involved with nanotechnology at the University.
The new staff and training procedures should especially help external users who are relatively unfamiliar with nanotechnology, Martin said.
“Now, instead of having to search for a lot of answers … (outside users) are a little more guided.” Martin said, “The training is a new thing; it’s more formalized. A lot of people are getting a lot of help so things should be easier.”
Najafi said the exchange of ideas that will accompany an influx of outside researchers should be beneficial for all involved.
“We can learn from them, and they can learn from us,” he said. The coordination between departments within the University as more faculty take advantage of nanotechnology resources should also help all involved advance their respective research, Najafi added.
This is already happening to an extent. Najafi referred to an instance when a geology professor with no nanotechnology experience was able to take advantage of the SSEL facilities to create an artificial rock for a project.
As much as it has benefited the University community, nanotechnology has been good for Ann Arbor’s economy as well. An entire industry of micro- and nanotechnology startups has sprung up around the area thanks to the facilities at the SSEL, Terry said.
“Without these facilities, those companies wouldn’t be here,” he said.
Nanotechnology has the potential to benefit the state of Michigan as well, said John Bedz, director of the Michigan Small Tech Association — an organization dedicated to promoting micro- and nanotechnology investment in the state.
“Material sciences have always been particularly important to the state’s economy, and the ability to work at this scale will make nanotechnology an important part of the future,” he said. “Nano-enhanced applications will find their way into everything. Anything that’s made of something can benefit from nanotechnology.”
Bedz cited Telurex, a Michigan company, as an instance of nanotechnology’s contribution to the state’s economy. Based in Traverse City, the company has developed cup holders that can change temperature to keep hot drinks warm or cold drinks cool based on nanotechnology.
Bedz also said the auto industry, which is always looking for stronger, lighter materials, could look to nanotechnology.
Research at the University could also have a direct impact on fields such as the computer industry.
Linjie Guo, an EECS professor, is developing a procedure called nanoimprinting that could change the way microprocessors are made.
Currently, microchips are made using a technique called electron-beam lithography to “etch” the tiny circuits and patterns needed into a chip. This is becoming more and more expensive as processors get more complex. Guo and his colleagues have developed what they said is a more efficient process wherein a design can be “stamped” onto a surface using a template. The computer industry has taken notice.
“This technique is becoming quite successful,” he said. “The semiconductor industry has officially put this on their road map for their next generations of chips.”
Nanotechnology may seem like a lucrative field, but it takes a lot of upfront capital to get things started: The hourly rate for access at the SSEL can be upwards of $70 an hour for external, non-University users — materials not included.
But if you have the cash and an affinity for blue coveralls, the world of nanotechnology awaits. And the newly established NNIN should make things that much easier. Just don’t drop whatever it is you’re working on—chances are you’ll never find it.