Hahniel, are you an admitted PhD student? If so, you'll at least be given a 1-year fellowship. That's what they provided me with, since NSF and NDSEG deemed me unworthy. After the first year, you'll be under an RA with your advisor.
My research deals with studying the mechanical properties of thin film materials. What kind of thin films are you interested in?
phsu, I liked Caltech when I visited, and I would have been happy to go there, but it was just too similar to my college (small tech school). The materials science department is small, and there isn't a whole lot of overlapping research between profs, so you really should be certain of who you want to work for. The profs were nice, and I got along with the grad students well. Eh, not quite sure what else to say. Caltech is a special school, and it's not a fit for everyone. I liked it, but Stanford was a better fit for me. Enjoy your stay in Pasadena!