Plasma enhanced CVD deposition of titanium oxide for biomedical applications

Radio frequency plasma enhanced chemical vapor deposition (RF PECVD) of titanium oxide films for bactericidal applications is reported. Titanium tetrachloride was used as a precursor compound, and the depositions were performed in the presence of oxygen. The films were deposited on glass and cotton textile substrates. Optical properties, and namely refractive index and extinction coefficient, of the films deposited on glass were used as criteria for their quality. Bactericidal properties were studied using cultures of K12 strain of Esterichia coli and the ultraviolet light C (UV-C) irradiation. An effect of an RF power of the discharge on both the optical and the bactericidal properties of the films was investigated. The results showed a substantial enhancement of the bactericidal activity of UV irradiation for the surfaces modified with the presented process. A strong correlation between the bactericidal efficiency of the films and their refractive index has been observed. The morphology and elemental composition of the coatings applied to cotton textile were also investigated using electron scanning microscopy (SEM) and energy dispersive X-ray (EDX) technique.