Mechanics and electricity properties of Cu/Ti thin film

Cu/Ti metallic thin bilayer films, xCu/yTi/Si (x,y=10nm, 20nm, 30nm),were deposited by DC magnetron sputtering technique. XRD was used to examine the crystallization structures of Cu/Ti thin films. A four-point probe method was applied to measure the sheet resistance of Cu/Ti films. Sheet resistance changes obviously with the variation of Ti film thickness when Cu film thickness is smaller than 20nm but inconspicuously when greater than 20nm. The hardness and Young´s modulus of Cu/Ti thin films were measured by nanoindentation with a continuous stiffness measurements (CSM) technique. The hardness decreases with the sublayer thickness increasing. The Young´s modulus decrease with the Cu film thickness increasing when Ti film thicknesses are 10nm and 20nm, and it reduces at the beginning and then increases when Ti film thickness is 30nm. If the Cu film layer keeps the same,the Young´s modulus are all following the trend of that reducing at the beginning and then increasing.