Day 2

Yesterday, I continued working on the hydrogel layer-by-layer assembly system I had created last time by adding two bilayers, measuring the thickness, adding two more bilayers, and measuring the thickness again, all with the goal of being able to eventually chart the growth regime. Before I could actually add the bilayers, though, I had to replenish the necessary solutions and solvent mixes, which involved some fun times with a giant jug of methanol.

The actual addition of the bilayers is a somewhat annoying process because it entails rotating the silicon wafers throughout sectors of a petri dish and rinsing them off in between. In theory, each wafer should only be in each sector for exactly ten minutes because some grad student no longer there once told another grad student no longer there who then mentioned in passing to someone who informed the undergrad I work with who in turn told me that ten minutes is the ideal time. In practice, each wafer is there for anywhere between eight and eighteen minutes. One of the grad students did tell me, however, that in Russia they once had to make 24-bilayer wafers using this same method, so I was grateful that I only needed to add a total of 4 for now. 

During the waiting periods, I helped out with a lot of random tasks, like measuring thicknesses of another wafer system, playing with Excel sheets, and learning to use the contact angle machine. This last item was particularly cool for me because whenever I had done contact angle measurements at school, we used an especially unsophisticated method that involved magnifying the droplet and measuring, by hand, with a protractor. This machine was much cooler because a needle was used to precisely deposit the droplet and then the software measured the contact angle for you.

I then measured the thicknesses of my own wafers using the ellipsometer - this fickle piece of equipment and I are becoming fast friends, although I have to say it's a bit of a complicated love-hate relationship at times - and discovered that my data makes no sense. Things that should have grown chose to shrink, and vice versa, which means I'll have some more fun times attempting to figure out why this should happen in general and why this should happen to me, specifically.