Fabrication of free standing, three-dimensional, fibrous, thin film substrates of parylene C

Microscale ultraviolet lithography to pattern a silicon wafer, spin coating of a layer of soap solution and physicochemical vapour deposition of two thin films of parylene C were sequentially used in a seven-step procedure to fabricate free standing, three-dimensional, fibrous, thin film substrates of parylene C for biomedical application. The effects of the length scales of the photoresist pattern on the wafer, the flowrate of the reactive monomer flux of parylene C and redistributive diffusion of the monomer molecules on the top surfaces of the thin film substrates were established. The top surface morphology of a thin film substrate is controlled by the photoresist pattern and the volumetric morphology of a fibrous thin film. The bottom surface of the thin film substrate acquires a multiscale morphology both from the photoresist pattern and from the baking of the soap layer.