| 摘要 |
PURPOSE: A method for forming a multilayer metal line using dual damascene processing is provided to be capable of preventing deformation of etch profile. CONSTITUTION: The first interlayer dielectric(33) having the first metal line(32) is formed on a substrate(31). The second interlayer dielectric(36) having a metal line(35) is formed on the first interlayer dielectric(33). The third interlayer dielectric(37) and an etch stop layer(38) are sequentially formed on the resultant structure. The first via hole(40a) to expose the first metal line(32) and the second via hole(40b) to expose the second metal line(35), are formed by selectively etching the third interlayer dielectric, the etch stop layer and the second interlayer dielectric. The fourth interlayer dielectric(41) is formed to generate voids in the first via hole(40a) and to entirely fill the second via hole(40b). By selectively etching the fourth interlayer dielectric(41), a trench(43) having a relatively wide line-width compared to the first via hole(40a) is formed and the second via hole(40b) is exposed at the same time.
|
