Interview by Michael Flatt
The clean room is kept at a cool 62 degrees with 40 percent humidity at all times. UB engineers working in the room must wear head-to-toe suits to keep their dead skin cells from contaminating the sterile environment. Precautions like these help protect the room’s sensitive machines, like a $1.4 million scanning electron microscope used for, among other things, examining metal samples for microscopic defects, and a molecular beam epitaxy (MBE) machine that deposits single-crystal layers of metal onto a desired object—useful for making LEDs, lasers and other products. David Eason, the clean room’s director, co-designed the MBE machine while working on his PhD at North Carolina State University in the mid-’90s. Now it resides at UB as one of the clean room’s centerpieces.
The clean room is split into multiple bays, and each one is cordoned off by a chase, a space where you put all your water and electricity and other services out of the way while you’re working in the bay. It lets you do some dirty work without contaminating the rest of the room.
It’s not possible to write too much. You may grow 10 films, or epitaxial layers, over 10 months. Later, you discover film number three was the good one, and you can’t remember what you did on film number three. So I have all the notes going back to 1995.
When you open up the machine, you have to use this to pull the toxic chemicals out of the air, like arsenic and cadmium, so you don’t breathe them. We named it Snuffy, as in Snuffleupagus.
That’s my PhD adviser’s design. It’s gravity-fed, so you fill the tank with liquid nitrogen and gravity pushes it through the hose into the deposition chamber. We use it to control temperature, which we want as low as possible to keep the air pressure low so that nothing interferes with the beam of particles being deposited. We can get it down to 10 degrees Kelvin, or -442 degrees Fahrenheit.
That’s our lucky charm. At one point, the MBE was being used by Chinese researchers. This work is like alchemy; there’s a lot of trial and error. Sometimes you can repeat your results, and sometimes you can’t. So people get very superstitious.
There are goats and horses as well. We put them on top of valves to identify them. Instead of some clunky description with a technical name, it’s just the goat or horse valve.