Growth and structural properties of Molybdenum thin films deposited by DC sputtering

Deposition of molybdenum (Mo) thin films on soda-lime glass substrate by simple DC sputtering is reported as a function of argon pressure. The films are characterized by X-ray diffraction (XRD), Atomic force microscope (AFM), Scanning electron microscope (SEM), Resistivity and specular reflectivity measurements. XRD scan showed only strong line of Mo (110) and weak line of (211) suggesting that the films are preferred oriented along (110). AFM revealed that the films composed of spherical grains with RMS roughness of 3 to 8 nm. It is found that as the Ar pressure decreases from 3.0 to 1.3 Pa, the roughness (RMS) of films decreases from 8.2 to 3.4 nm and sheet resistance decreases from 5.3 to 1.1 Omega/sq. Roughness of films also affect the optical reflectivity. The average reflectivity of Mo films is about 55 % in the visible region. The columnar growth, observed form the cross section SEM images, indicates the dense morphology of the Mo films.