Atomic vapor deposition of Ru and RuO2 thin film layers for electrode applications

Ru and RuO2 thin films for advanced metal gate applications were deposited on 200mm SiO2/Si substrate by the novel deposition technique atomic vapor deposition (AVD(TM)). AVD(TM) was carried out in an Aixtron Tricent(TM) system using liquid delivery of the Ru precursor. The creation of Ru- and RuO2-films is controlled by varying the O2 flow and deposition temperature. Ru layers with a near bulk resistivity of 10muOmegacm and a uniformity of 2% for 20nm film thickness were obtained at 450 deg C deposition temperature. The smooth Ru layers have a thickness uniformity of about 2% and a roughness < 1nm. XRD measurements exhibit multi-crystalline Ru-films with a preferable orientation along the (002) plane. Adding O2-flow RuO2 layers were grown at 380 deg C. RuO2-films with a resistivity of about 80muOmegacm and < 2% uniformity were achieved for 30nm thick films. The roughness of the RuO2 layers is about 2nm for 10-20nm thickness. No Ru-crystallites could be detected in the RuO2 layers by XRD. The thermal stability of the grown Ru and RuO2 films was investigated by rapid thermal annealing in O2 and N2 atmosphere. Ru films were found to be stable in N2 up to 900 deg C and up to 500 deg C in O2. RuO2-layers have been shown to be stable in O2 up to at least 600 deg C.