Platinum bottom electrodes formed by electron-beam evaporation for high-dielectric thin films

Abstract

Platinum (Pt) bottom electrodes have been prepared on SiO2/Si substrates at various deposition temperatures by electron-beam evaporation. Subsequently, (Ba0.5Sr0.5)TiO3 (BST) films were grown under identical conditions by rf magnetron sputtering. It was found that the crystallinity of BST thin films on the Pt bottom layers was strongly dependent on that of Pt films. The surface morphology of BST films appeared to be closely related to the change in the stress of Pt films during BST deposition. In addition, the stress of Pt fill has been proven to affect the electrical properties such as current-voltage characteristic and capacitance-voltage characteristic.