Comparasion between TiO2 thin films deposited by DC and RF sputtering.

Abstract

This paper compares titanium oxide (TiO2) thin films deposited by RF and DC sputtering. Structural characterization was used to investigate the morphology of TiO2 thin films. Both films show the rutile and anatase crystal structure; ellipsometry show thickness and refractive index of 50 nm and 2.43 for the TiO2 deposited by DC sputtering and 40 nm and 2.32 for the film by RF sputtering; AFM shows the roots mean square (RMS) roughness of 6.5 nm and 8 nm for TiO2 deposited by DC and RF sputtering, respectively. For electrical characterization was developed MOS capacitor; from them was possible to determine which method forms the best dielectric film, defined by high dielectric constant value (high-k), lower charge density (Q0/q) and flat-band voltage (VFB) around -0.9V. Therefore, the best method to deposit TiO2 is DC reactive sputtering; because this method showed a better electrical conditions and a well-defined crystalline structure