Pulsed laser deposition of conductive SrRuO₃ thin films

In this article we describe the pulsed laser deposition of smooth, particulate-free, and high conductivity SrRuO₃, which are well suited for use as bottom electrodes in high capacity integrated thin-film capacitors. The films were heteroepitaxially grown on (100) LaAlO₃ substrates at temperatures above 650°C. Scanning tunneling microscopy measurements revealed that higher deposition temperatures produced larger grain sizes, and it was found from x-ray diffraction and four-probe tests that higher temperatures also led to improved film crystallinity and conductivity, respectively. At a deposition temperature of 775°C, the room-temperature resistivity of SrRuO₃ films was 280 μΩ cm, and the residual resistivity ratio was 8.4, making these materials excellent candidates for use as thin-film electrodes.