Spin coating

Spin coating is a procedure used to deposit uniform thin films onto flat substrates.

[1] Rotation is continued while the fluid spins off the edges of the substrate, until the desired thickness of the film is achieved.

[2] Pioneering theoretical analysis of spin coating was undertaken by Emslie et al.,[3] and has been extended by many subsequent authors (including Wilson et al.,[4] who studied the rate of spreading in spin coating; and Danglad-Flores et al.,[5] who found a universal description to predict the deposited film thickness).

Spin coating is widely used in microfabrication of functional oxide layers on glass or single crystal substrates using sol-gel precursors, where it can be used to create uniform thin films with nanoscale thicknesses.

[7] However, spin coating thicker films of polymers and photoresists can result in relatively large edge beads whose planarization has physical limits.