Preparation of SrRuO₃ films for advanced CMOS metal gates

Abstract

We report on the growth and properties of SrRuO3 films for application as metal gates for CMOS devices. The films were grown at 500°C by metal-organic chemical vapour deposition on Si substrates with thermal SiO2, atomic-layer deposited Al2O3 and HfO 2 dielectric films. The films exhibit room temperature resistivity below 1 mΩ cm. We have analysed the interface between the SrRuO 3 metal gate and the oxide film by Rutherford backscattering and secondary ion mass spectroscopy. Annealing in an oxygen atmosphere and forming gas (90% N2 +10% H2) were employed for testing the stability of the SrRuO3 metal gate. Finally, electrical characteristics of the metal gate stack were investigated by high-frequency capacitance-voltage measurements. The properties of metal-organic chemical vapour grown SrRuO3 gate electrode are analysed with regards to integration in CMOS devices. © 2004 Elsevier Ltd. All rights reserved.