Change of Tg with film thickness

Many techniques needed to be developed to create and monitor these new thin film systems. An accurate method for producing thin polymer films was the first objective of this thesis research. The proposed solution to the problem was spin coating. First a polymer solution was made and was pipetted onto the desired surface. Next, the 

Several variables can control the film thickness of the final product. Extrand looked at some of the experimental parameters in spin coating. The solvent used to make the solution does affect the final thickness of the film. Different viscosity and solubility can make PMMA films cast from a cyclohexane solution twice as thick as those cast from a toluene solution. The research also showed that thickness increased as spin speed decreased as would be expected. The amount of solution applied to the wafer did not affect the thickness as long as there was enough present to cover the surface. Any excess was simply flung off the surface by centripetal forces. 

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