Plasma polymerization of allylamine/3‐aminopropyltriethoxysilane mixtures: Surface nitrogen control

A study has been conducted to determine the effects of gas‐feed composition and RF power on the deposition rate and on the surface nitrogen content of thin films produced by plasma polymerization of allylamine/3‐amino‐propyltriethoxysilane (AA/3‐APTS) mixtures. It has been found that while the deposition rate decreases slightly by increasing the AA content in the mixture, the surface nitrogen content, determined by XPS as N : Si molar ratios, increases up to a value of 8 : 1. Moreover, the nitrogen increase is not linear with the AA concentration and a maximum in the N/Si values is found for AA/APTS ratios close to 3 : 1, at all RF powers. The discussion on the polymerization mechanism for the mixture is based on evaluating and combining the behavior of each component, when plasma‐polymerized alone in similar conditions.