Effect of substrate temperature on the properties of electron beam deposited tantalum films

In this work, the effect of substrate temperature (room temperature - 250 °C) on the structural, morphological and electrical properties of tantalum films deposited on Si/SiO2 (100) substrate by electron beam evaporation technique was presented. The structural analysis of the deposited films was done using X-ray diffraction (XRD). The XRD patterns revealed the growth of tetragonal crystalline structure (β-Ta) and that the crystallinity of the films increased with the increase of substrate temperature. The field emission scanning electron microscopy (FESEM) images showed that the film morphology was smooth with fine spherical particles on the surface. The film thickness measured using a cross-sectional FESEM was found to increase from 97 nm to 165 nm with the increase in substrate temperature. The resistivity of tantalum films was found to decrease from ~ 350 μΩ-cm to ~ 220 μΩ-cm with increasing substrate temperature from room temperature - 250 °C respectively.