1. A method of depositing an iridium silicide film, the method comprising exposing a substrate surface maintained at a temperature in the range of about −25° C. to less than 300° C. to iridium hexafluoride and a silicon precursor, wherein the entire substrate surface is maintained at the temperature in the range of about −25° C. to less than 300° C. during the method, wherein the substrate surface comprises a first material consisting essentially of silicon and a second material comprising silicon oxide, silicon nitride or Al₂O₃ and the iridium silicide film is deposited selectively on the first material over the second material at a rate 15 times greater on the first material over the second material.