Variations of morphology of fluoropolymer thin films versus deposition conditions

Abstract

Fluoropolymers (FP) are materials with a combination of excellent physical and chemical properties which make them useful in various industries. Thin films of these almost insoluble polymers were deposited with decomposition-evaporation of bulk FP in a vacuum. The pretreatment of the evaporated FP, the pressure of the emitted gas, the activation with accelerated electrons, the additional radio frequency (RF) plasma and the external magnetic field had complex effects on the morphology and relief of polytetrafluoroethylene (PTFE) films. Thin PTFE films with a roughness from 2 to 100 nm were produced. A PTFE film grown in a magnetic filed had nanoworms on its surface. The hardness of PTFE films was increased using low power RF plasma during deposition. The hardness of polychlorothrifluoroethylene (PCTFE) thin film was significantly smaller, whilst the relief of PCTFE films was rougher than that of PTFE films. A conformal PTFE coating was deposited on a nanostructured plastic surface using PTFE evaporation with electron activation and low power RF plasma.

Optical and Mechanical Properties of Thin PTFE Films, Deposited from a Gas Phase

“…The deposition parameters influenced properties of the PTFE film in complex interrelated ways. [ 63 ] The properties of the PTFE film depend on the pressure of perfluorinated fragments in chamber, deposition rate, rotation of substrate, and power of additional RF LTP. In general, the growth process starts from fragment adsorption, chemisorption, and surface diffusion to find a partner to form the nucleus.…”