Properties of Ruthenium Films Prepared by Liquid Source Metalorganic Chemical Vapor Deposition Using Ru(EtCp)₂ with Tetrahydrofuran Solvent

Abstract

Pure Ru thin films were deposited on SiO 2 /Si substrates, using Ru(C 2 H 5 C 5 H 4 ) 2 with C 4 H 8 O (THF) solvent, by liquid source metalorganic chemical vapor deposition. The Ru single phase could be obtained under all growth conditions. For temperatures below 350°C, deposition occurred in the surface reaction region because the kinetics increased exponentially as a function of the deposition temperature with an activation energy of about 1.1 eV. Above 350°C, the deposition was controlled by the mass transport process. Step coverage for the Ru thin films deposited at 300–325°C with an aspect ratio of 3.3 was about 100%. The Ru thin films grown at 325°C showed a dense and smooth microstructure and had resistivities of <100 µΩ·cm.