(Edmonton) Department of Physics technician Greg Popowich has been named the 2012 Nat Rutter Technician of the Year for the University of Alberta. The award is sponsored by the Sigma Xi Scientific Research Society.
Popowich works with equipment for condensed matter physics (CMP) experiments: ultrafast lasers, electron microscopes, thin-film deposition equipment, ultra-high vacuum technology and low temperature refrigeration units.
However, his career has not always been in high tech. In fact, Popowich began his working life in the depths of B.C. coal mines.
Growing up in Fernie, B.C., the mechanically inclined Popowich was rebuilding the two-stroke engines of his motorcyles by the time he was 13. Years later, he was driving and servicing 200 tonne trucks as a coal miner. "After four and a half years in the mines, I thought, 'Okay, time to go back to school.'"
In 1993, Popowich went to the DeVry Institute for a degree in electronics. He landed a job with a semiconductor equipment firm in San Jose, California called Ultratech Stepper. The work involved a lot of travel - including a memorable three-week stint in China - but after three years, Popowich and his family wanted to settle down. "We wanted to come back to Canada."
He got a job at a UAlberta spin-off company, the Alberta Microelectronics Centre (now called Micralyne), where he met one its regular clients, Mark Freeman. In 1999, Freeman and two other Department of Physics faculty members, Frank Hegmann and Ray Egerton, pooled research funds to hire a technician for condensed matter physics experiments. Popowich was the successful candidate. (Afterwards, Popowich discovered that Freeman was a collaborator with one of his previous customers in Silicon Valley - Popowich may have worked on Freeman's projects long before they actually met.)
In 2000, Popowich succeeded a retiring Physics technician. From that point on, his work became more oriented to specialized apparatuses and mechanical design. "I took a few courses over the last few years. A machine shop course at NAIT and an Ultra High Vacuum Techniques course at an American Vacuum Society (AVS) course in San Jose, to name a few. I am constantly expanding my skill set and although it is still an important part of my position, I am getting further and further away from pure electronics."
In the nomination submission for the Nat Rutter Award, assistant professor John Davis wrote: "There isn't even a faculty member in our department that has all those skill sets, because Greg becomes an expert in the area of each and every condensed matter faculty member."
Popowich takes pride in his work. He values working with all the researchers, students (many of whom he has trained to use the equipment) and other technicians in the department.
"When I think about the award - "Technician of the Year" - I think, I didn't do that all myself," says Popowich. "I have a whole team of people that I work with."
Q & A with Greg Popowich
When Greg Popowich started working at the University of Alberta, he was asked to maintain or repair some of the equipment being used in condensed matter physics experiments. Gradually, he learned to use all the equipment well enough to maintain, repair, modify and train students to use them. As with his attention to custom work, Popowich rejects a one-size-fits-all approach to training. "I've learned to identify which students are scared and which are over-confident."
Here are the major apparatuses Popowich works with now.
Ultra Low Temperature Dilution Refrigerator
Popowich is currently finishing up work on what he feels could be the most complicated and challenging project of his career, the ultra-low temperature dilution refrigeration system for John Davis.
"This was really outside of my expertise. Electronics, soldering, machining, I've done," says Popowich. "But it is a whole different world getting as close as possible to absolute zero. There is so much more to consider."
The core of the system is a helium dilution refrigeration unit that was donated to Davis. "We're refurbishing it," Popowich says. "I'm going to have to totally re-wire it and replace all of the helium capillaries. The old-style vacuum connections have already been updated to modern fittings."
Popowich also designed the support structure, which was required to be as free from the effects of ambient building vibrations as possible. The pillars are actually hollow aluminum columns filled with sand; each one is capped with a disc of specially chosen high-density plastic. The disc sits on the sand, but away from the insides of the pillar. On top of the discs, Popowich placed airbags on which the legs of the optical table sit.
He arrived at this elegant solution after years of observation and experience. "I adapted an auto-level system that I designed based on existing isolation tables."
Popowich has built a second support structure for the lab. It will hold a new dilution fridge, which is currently being built by Oxford Instruments in England.
Transmission Electron Microscope
The transmission electron microscope (TEM) intimidates more students than any other CMP apparatus. It is a very large microscope with a bewildering number of possible adjustments to make. Popowich says it is one of the first pieces of equipment he learned to use and to teach people to use. Eventually, he became the expert technician on it.
"We had a service contract on it, but after a few years we weren't using the service people," he recalls. "As I gained more experience operating the instrument, I was able to identify and repair problems quicker than they could fly someone out." Popowich still maintains a good relationship with the manufacturer, Japan Electron Optics Lab (JEOL).
Ironically, the 21-year-old scope is giving more accurate readings since moving in 2007 into CCIS Phase 1 "Before, it was in Chemistry West next to a machine shop, so there would be a lot of noise (physical vibrations) affecting the beam. We also suffered temperature instability in the old location," says Popowich, who laid out the design of the new lab. "Temperature and vibration stability were the biggest concerns that we designed into the new lab."
Thin Film Deposition
"I work under Don Mullin in this lab, so there are years of experience to learn from there," says Popowich. Mullin is a past winner of the Nat Rutter award.
Popowich and Mullin are constantly updating and modifying the existing evaporators to meet the researchers' needs. "I once designed a sliding shutter to allow the production of a stepped film (film treated in a way that gives it varying thickness), then months later adapted it to produce a gradient film." Popowich recently built an organic evaporator and a second e-beam evaporator system for the thin film lab because the first system was used so frequently.
Ultra-high Vacuum (UHV) Multicluster Tool
Mark Freeman's UHV system has been in the department almost as long as Popowich has. Although it was designed and purchased from outside suppliers, it arrived as a box of parts needing required assembly. "Each flange on the system has to be bolted on and tightened to torque specification," says Popowich. "There are well over 1,000 bolts on that system!"
Popowich had to disassemble the system to move it from the old Physics building into CCIS Phase 1 in 2007. When the time came to re-assemble the machine, Popowich took the opportunity to improve it. "We modified it to be more functional toward new projects."
Popowich also helped a graduate student, Jacob Burgess, design and build a UHV "suitcase" in which to transfer material from the ultra-high vacuum deposition chamber to the nearby scanning tunnel microscope (STM). Popowich says the distance is not great, but "exposing the samples to air for even the shortest amount of time can render them useless in the STM."
Near-field Scanning Optical Microscope (N-SOM) and Scanning Tunnel Microscope (STM) for the Ultrafast Nanotools Lab
This new lab in CCIS Phase 1 was built for Frank Hegmann. "It was great to be involved from day one with this project," says Popowich. "We met with the project management office [the University of Alberta office that coordinates construction projects] to make sure the facilities we required were put in and in the right place." Popowich ensured that the new lab would be supplied with enough power. With the help of geophysics technican Lucas Duerksen, Popowich installed optical benches and an overhead rack system that Popowich designed to manage all the electronics. As the equipment arrived, Popowich installed each system according to the manufacturer's specifications.
This lab is home to the near-field scanning optical microscope (N-SOM). "During the installation [into the new lab], I was the guy to learn to run it and train the students."
It was a very busy time. As he was setting up the N-SOM, the new scanning tunnel microscope (STM) for the lab also arrived. Complicating matters, a part of the STM broke off in transportation. "As I uncrated the STM, I noticed one of the UHV feedthroughs dangling. It had already arrived late and we were anxious to get it installed. To save time, I contacted the manufacturer and convinced them to let me remove the prep chamber and send it to them for welding. They agreed. Two weeks later, the repaired chamber showed up and I completed the repairs."
But the STM problems continued. After the shipping damage was repaired and the rest of the STM set up, the apparatus's active isolation system did not cancel the ambient vibration "noise" in the lab. As a result, the microscope could not do what it was purchased for: it could not achieve a high enough resolution to see structures at an atomic level.
Popowich had to fight for a resolution to the problem. "There were two companies involved. One manufactured the STM and the other the vibration isolation system. Neither one felt it was their problem so they did not send anyone up to actually see what was going on." He collected data over a few days and finally convinced the manufacturer of the vibration isolation system that it was not working as designed. "When they finally came out to see the entire system, they realized they had underestimated the total weight of the system and the passive part of their isolation system was too stiff."
Popowich's tenacity paid off in two ways. First, the scope worked. Second, as the first person to test the now-working system, Popowich was looking at a test sample when something caught his eye - the sample's atomic structure.