STRESS TUNABLE TANTALUM AND TANTALUM NITRIDE FILMS

摘要

Residual stress present in a thin film of tantalum or tantalum nitride (TaN, where 0 x ≤ 1.5) film can be controlled (synchronized) by controlling certain process parameters in the thin film coating process. Thin film coating, the particular process parameters associated with the Ta and TaN _x For example a thin film sputter coating are as follows: That is, the power for the sputtering target, the pressure of the process chamber (also increases in the normal, direct current applied substrate bias power) (variety of gas and the concentration of the ions in the chamber), the substrate DC offset bias voltage, and a thin film of the substrate to be coated It is the temperature. When the Ta and TaN _x film is coated by IMP sputtering, the power of the ionization coil may be used for co-movement of the film stress. By using IMP as a sputtering technique makes it possible to control the ion bombardment on the coating film surface. Typically, a tantalum thin film by coating method using IMP was about 1 × 10 ⁺¹⁰ dynes / ㎠ (tensile stress) to about -2 × 10 ⁺¹⁰ dynes / ㎠ (compressive stress), the residual stress of the range according to the above-mentioned process parameters It denotes a. A tantalum nitride thin film covered with the IMP process may be synchronized to indicate the residual stress in the same range as in the above-described Ta film. Any of the residual stress of the Ta or TaN _x film may be decreased to about 6 × 10 ⁺⁹ dynes / ㎠ to about -6 × 10 ⁺⁹ dynes / ㎠ range using the above-described synchronization technique. The Ta and TaN _x thin film can also be continuously synchronized to the coating with ion bombardment process and annealing process of the coated thin film to the thin film surface. The barrier layer performance of the thin film can be improved by coating a thin film at a substrate temperature of at least 300 ℃.