Optimization of organic bottom anti-reflective coating (BARC) thickness for dual damascene process

摘要

A method of manufacturing a semiconductor device includes forming a second barrier layer over a first level, forming a first dielectric layer over the second barrier layer, forming a second dielectric layer over the first dielectric layer, etching the first and second dielectric layers to form an opening through the first dielectric layer and the second dielectric layer, and depositing an anti-reflective material in the opening at an optimal thickness. The optimal thickness is determined by minimizing a standard deviation of reflectivity of the anti-reflective material. After etching the first dielectric layer, the anti-reflective material can then be completely removed and the second barrier layer is etched to expose the first level. The trench and a via are then filled with a conductive material to form a feature.