Measurement and modeling of solvent removal for spin coating

Abstract

Solvent concentration is an important factor for spin-coated film planarization. Two techniques, one an on-line optical method and the other an off-line gel permeation chromatography method, have been used to investigate the coating concentration change during spinning. The experimental observations are compared with the spin-coating model predictions. The modeled concentration and thickness are in close agreement with experiment. Under certain conditions, the spin-coating model can be significantly simplified. These conditions are discussed.

Characteristics of thin cellulose ester films spin-coated from acetone and ethyl acetate solutions

“…In this simple technique, polymer solution is dropped on a static substrate surface, which is then rotated at a given angular velocity during a given period of time. The film thickness is mainly controlled by the concentration of the polymer in solution, while polymer molecular weight (Schubert 1997), spinning velocity (Hall et al 1998), spinning time (Gu et al 1996) and solvent evaporation rate (Meyerhofer 1978;Walsh and Franses 2003;Strawhecker et al 2001) are less important. On the other hand, morphology and roughness of thin polymer films depend on the solvent chosen for polymer solution preparation (Walsh and Franses 2003;Strawhecker et al 2001;Müller-Buschbaum et al 2001;Cui et al 2006;Lin et al 2004;Petri 2002), solution concentration (Schubert and Dunkel 2003) and spinning velocity.…”

Effect of solvent on nanoscale polymer heterogeneity and mobility probed by single molecule lifetime fluctuations

“…The existence of a low-N s plateau is probably due to the formation of a dense viscoelastic region at the exposed surface, at the early stages of the solvent desorption (during the spin coating or casting process) [25]. The formation of such a skin is undesirable in coating processes due to non uniformities in the polymer coating and a decrease in the drying rates [26].…”

Effects of Polymeric Dielectric Morphology on Pentacene Morphology and Organic TFT Characteristics

“…The dielectric constant (İ) of COP films is 2.3, thus the film thicknesses of the COP films were about 450 nm and 330 nm. Generally, the thickness of the resulting films depends on the concentration of the polymer in solution, polymer molecular weight, spinning velocity and spinning time [9][10][11]. Thus, the thinner COP films could be obtained with the higher BP solvent.…”