Process effects resulting from conversion to a safe-solvent organic BARC

The use of bottom antireflective coatings (BARCs) as a means for controlling substrate reflectivity and thin film effects, has become commonplace in today's wafer fabs. In an effort to simplify process integration, reduce environmental impact, and reduce processing costs, some next generation organic BARC materials have recently been introduced which are formulated with photoresist compatible solvent systems. This study examines the process effects of converting from the cyclohexanone based AZTM BARLiTM anti-reflective coating, to the recently introduced PGME/Ethyl Lactate based AZTM BARLiTM II anti-reflective coating. We will present a comparison of the optical properties of the two products, and examine i-line lithographic process effects including process latitudes, CD distributions, and coat defects, as well as post etch CD distributions, and dye sublimation during cure.