THE EFFECT OF BIAS POWER ON SOME PROPERTIES OF TITANIUM AND TITANIUM-OXIDE FILMS PREPARED BY RF MAGNETRON SPUTTERING

Titanium and titanium oxide thin films have been deposited on (100) si licon wafers and glass substrates by r.f reactive sputtering magnetron . Substrates have been r.f. biased during the growth of the him and th e influence of the bias power on some properties of the coatings has b een investigated. The results of the deposition rate measurements show that this is weakly affected when bias power is low. As the r.f. bias power increases, the deposition rate decreases strongly due to an inc rease of the layer density and resputtering phenomena. Atomic force mi croscopy showed that the surface morphology of metallic and oxide film s can be modified using bias treatment. Roughness analyses exhibited a similar evolution as the deposition rate and surface topography when bias power changes. Optical properties like refractive index followed the same variations as previous results. So, when r.f. bias power incr eases, various phenomena take place and different zones can be defined from these investigations. Argon ion to atom arrival rate ratio and a verage energy per deposited atom have been calculated from experimenta l values of current density applied to the substrate and energy of arg on ions impinging on the growing film. Their evaluations have been dis cussed for metallic and oxide materials. (C) 1998 Elsevier Science S.A . All rights reserved.