Modeling of Poly(methylmethacrylate) Viscous Thin Films by Spin-Coating

Abstract

A predictive film thickness model based on an accepted equation of state is applied to the spin-coating of sub-micron poly(methylmethacrylate) viscous thin films from toluene. Concentration effects on density and dynamic viscosity of the spin-coating solution are closely examined. The film thickness model is calibrated with a system-specific film drying rate and was observed to scale with the square root of spin speed. Process mapping is used to generate a three-dimensional design space for the control of film thickness.

Interfacial Effects of the Photophysics of Rhodamine 6G Ultra-Thin Films on a Poly(methylmethacrylate) Surface

“…We previously reported that the surface morphology of the PMMA films formed by spin coating can have a quasi-periodic structure. , These surface deformations are vitrified Rayleigh–Bénard–Marangoni convective instabilities that arise during the film drying portion of the spin coating process . For very thin films of thickness less than 75 nm, the surfaces were nearly flat.…”

“…PMMA is deposited by spin coating on a cleaned glass surface. By varying the spin coating variables, the thickness and surface morphology of the PMMA can be controlled. − PMMA is unique such that periodic surface structures (wrinkles, striations, or corrugations) can be with wavelengths in the range of tens of μm and amplitudes in the range of tens of nm. Unlike PVDF, the PMMA surface roughness can be controlled, which allows a comparison between the two polymers.…”

Evolution of Surface Morphology of Spin-Coated Poly(Methyl Methacrylate) Thin Films

“…The total drying rate during spin-coating is related to solvent static evaporation rate e and the square root of spin speed (ω) [ 29 , 30 ]. Therefore, the drying rate can be calculated from Equation (8).…”

“…The static evaporation rate for toluene was calibrated with the film thickness model and found to be 140 nm/s 1/2 [ 30 ]. The link between surface structures and drying rate has been established [ 31 , 32 , 33 ].…”

Fabrication by Spin-Coating and Optical Characterization of Poly(styrene-co-acrylonitrile) Thin Films

“…For a given solvent, D is approximately proportional to µ 0.36 . However, it should be taken into account that the viscosity may depend on the polymer concentration (wt) in a complex manner [31]. According to Weill [25], three different regimes can be distinguished: (i) for very dilute solutions, the solution is a pure viscous fluid whose viscosity is a linear function of the concentration (µ = µ 0 wt), (ii) in dilute solutions, the solution can be treated as a viscoelastic fluid (µ = µ 0 (wt) + µ 1 (wt) 2 ) and (iii) for highly concentrated solutions, the mechanical behavior of the solution is that of a viscous fluid (µ = µ 0 (wt) 5 ).…”