abstract |
Gap-fill and damascene methods are disclosed for depositing an insulating thin film of nitrofluorinated silicate glass on a substrate in a process chamber. A high-density plasma, generated from a gaseous mixture of silicon-, fluorine-, oxygen-, and nitrogen-containing gases, deposits a layer of nitrofluorinated silicate glass onto the substrate. For gap-fill applications, the substrate is biased with a bias power density between 4.8 and 11.2 W/cm2 and the ratio of flow rate for the oxygen-containing gas to the combined flow rate for all silicon-containing gases in the process chamber is between 1.0 and 1.8, preferably between 1.2 and 1.4. For damascene applications, the bias power density is less than 3.2 W/cm2, preferably 1.6 W/cm2, and the flow rate ratio is between 1.2 and 3.0. Using optimized parameters, the thin film has a lower dielectric constant and better adhesion properties than fluorosilicate glass. |