| 摘要 |
PURPOSE: A copper metallization method for a semiconductor device is provided to enhance reliability of copper metallization by using a diffusion barrier. CONSTITUTION: A semiconductor substrate(10) is provided with a dielectric film(20) thereon. A via pattern is then formed in the dielectric film(20), and a titanium nitride thin film and an aluminum thin film are successively deposited on the dielectric film(20). The combined thin films act as a diffusion barrier(30). Next, a copper layer is deposited enough to fill the via pattern in the dielectric film(20). Thereafter, by a planarization process, a copper metallization pattern(50) is obtained in the planarized dielectric film(20). In particular, the diffusion barrier(30) is interposed between the copper metallization pattern(50) and the dielectric film(20). Aluminum in the diffusion barrier(30) is diffused in the titanium nitride thin film, and further, grain boundaries of the titanium nitride thin film are stuffed with the diffused aluminum. Accordingly, the succeeding diffusion of copper is effectively prevented. |
