So, it was probably sub-optimal that I moved to the other side of the country, and then quit blogging. But, amazingly, only a week or two ago I had an actual request from someone that I update my blog. So, my adoring fan, this one's for you. (If you even remember who you are.)
I've been thinking lately about the difficulty in keeping in touch with my sisters. (Not doing anything about it, mind you. Just thinking about it.) Over the last few months we've been busy with moving and kids and life in general. And my sisters have been busy with moving and kids and more kids, and jobs and college and life in general. (Aside: I seriously don't understand how people survive with more than 2 kids. My house is about a foot deep in toys and blankets and clothes and mess. Is my sister's house 2 feet deep?) The specific thing that stuck out in my mind was that I'm really not sure that any of my sisters could give a description of what I do for a living these days. (Whether they could do that before I got a new job, we may never know.) So, for my sisters, and anyone else who is tagging along on this adventure, here is what Clark does at work now.
Hi, I'm Clark, and I'm a Process Engineer. My business card says that I'm a "Bulk Growth Process Engineer". Let's look at that title one piece at a time. "Bulk Growth" describes the fact that I grow big things. "Big" is relative, and in this case it means something you can hold in your hand. Our finished product is silicon carbide wafers. (see picture below) The bulk growth step is first, in which we grow crystals which are then sliced into wafers. One of the last steps that we do is to grow an epitaxial layer on top of the wafer. The epi growth is very thin, only a few thousandths of an inch. Which is why we get to describe our growth as "bulk". My dad gave me a hard time about the "Bulk Growth" part. I guess it sounds less than flattering.
Next comes "Process Engineer". The engineers are divided into three groups: Manufacturing Engineers, Process Engineers and R&D. I haven't used an analogy yet, so it's about time. If we were in charge of a fleet of cars, the MEs would be in charge of all the many day to day things. Oil changes, tires, fuel grades, tune-ups, that sort of thing. R&D people are at the extreme other end. They're in the back room drawing up some wild ideas for building a completely better car. You know, put the engine in the back, headlight that turns with the wheels, 6 wheels, fins, wankel engines, and all that good stuff. A lot of their ideas are probably going to fail miserably, but that's ok, provided that stumble into some really good stuff once in a while. In the middle are the PEs. PEs take something that is already working, and make a significant change, but without completely starting from scratch. The analogy here would be to re-build an engine, but leave the rest of things alone. (You like the car analogy? I'm trying hard to fit in in Michigan.)
So, before this gets any longer, what do I actually do? Well, today, I sat at a computer all day and drew pictures. (That's what I told Julia. And it's true.) We grow our crystals inside what is basically an intricate little graphite bucket. We put a wafer in there, along with a bunch of silicon and carbon, heat it all up until it's glowing and the silicon carbide vaporizes (it's like 2000 °C in there) and then condenses on the wafer, which slowly grows. Once it has grown big enough we let it cool down, take it out and slice it into lots of wafers. (We save some to repeat the process.) These graphite buckets are a bit more complicated than your average bucket, and we're regularly trying out minor modifications. One of my jobs is to produce the drawings that we send out to get the parts manufactured. Then, I set up experiments where I vary a few parameters, throw everything in the furnace and let it run for a few days and see if it worked or not. I collect up all the data and eventually get around to writing up a report detailing the findings. Is it better? Is it worse? (Or, better in some ways but worse in others.) And what have we learned in general about the whole process?
So, I feel like this has turned out both very generic and simplistic, but way to long at the same time. That's what you get for asking an engineer what he does.