Synthesis and characterization of Al2O3 and SiO2 films with fluoropolymer content using rf-plasma magnetron sputtering technique

Abstract

Articles you may be interested inCarbon film deposition on SnO 2 / Si (111) using DC unbalanced magnetron sputtering AIP Conf. Proc. 1554, 93 (2013); 10.1063/1.4820292Correlation of structure and hardness of rf magnetron sputtered silicon carbonitride films Growth dynamics and characterization of SiC quantum dots synthesized by low-frequency inductively coupled plasma assisted rf magnetron sputtering Synthesis and characterization of inorganic silicon oxycarbide glass thin films by reactive rf-magnetron sputtering Pure and molecularly mixed inorganic films for protection against atomic oxygen in lower earth orbit were prepared using radio-frequency ͑rf͒ plasma magnetron sputtering technique. Alumina ͑Al 2 O 3 ͒ and silica ͑SiO 2 ͒ films with average grain size in the range of 30-80 nm and fully dense or dense columnar structure were synthesized under different conditions of pressure and power. Simultaneous oxide sputtering and plasma polymerization ͑PP͒ of hexafluoropropylene ͑HFP͒ led to the formation of molecularly mixed films with fluoropolymer content. The degree of plasma polymerization was strongly influenced by total chamber pressure and the argon to HFP molar ratio ͑n Ar / n M ͒. An order of magnitude increase in pressure due to argon during codeposition changed the plasma-polymerization mechanism from radical-chain-to radical-radical-type processes. Subsequently, a shift from linear CH 2 group based chain polymerization to highly disordered fluoropolymer content with branching and cross-linking was observed. Fourier transform infrared spectroscopy studies revealed chemical interaction between depositing SiO 2 and PP-HFP through appearance of absorption bands characteristic of Siu F stretching and expansion of SiO 2 network. The relative amount and composition of plasma-polymerized fluoropolymer in such films can be controlled by changing argon to HFP flow ratio, total chamber pressure, and applied power. These films offer great potential for use as protective coatings in aerospace applications.