Growth and properties of ruthenium based metal gates for pMOS devices

Thinfilms of Ru, RuG2 and SrRu03 were prepared/or application as metal gates for sub-micrometer CMOS technology. The films were grown by metal organic chemical vapour depOSition at temperatures from 300 to 500 °C Room temperature resistivity of the depositedfilms rangedfrom 20 μΩcm for Ru up to 1 mS2cm for SrRu03. Stability of the gate electrodes in forming gas (90%N₂+10%H₂) and nitrogen atmosphere was examined. Optimised Ru, RuO₂ and SrRu0Msub>3 films were then depOSited on ALD (atomic-layer deposition) grown Hf0₂ dielectric films. Metal-oxide-semiconductor (MGS) structures were prepared using wet and ion beam etching 0/ upper electrodes. Work junction of the Ru-based metal gate electrodes extracted from the capacitance-voltage measurements was found to be close to 5 eV for all studied MOS structures.