AJA film characterization
I used the spectroscopic ellipsometer to measure several wafers deposited using the AJA system. I verified film uniformity as well as film quality using index of refraction as the metric. The term “w/ Bias” refers to an applied RF power over the substrate. The bias adds energy to the surface as adatoms re-arrange during deposition leading to a denser/smoother film (in theory).
It’s impressive that the silicon index of refraction is almost 3.97 at the onset of dispersion ~ 1.13 eV. The highest index I have seen with our Hopeman tool is 3.8. It would seem that the substrate RF bias increases film density.
Surface roughness still needs to be determined with an AFM.