This paper will evaluate the potential improvements with the addition of an aqueous based top antireflective coating to a Deep-UV process. This antireflective coating (ARC) is resistant to intermixing with the resists and is removed during the normal develop operation. A logic IC with 0.15- 0.18 micrometers design rules will be the primary test vehicle, concentrating on Contact/VIA levels. Performance will be compare with and without the top ARC. Uniformity of measured critical dimensions (CD) will be compared. CD/dose swing curve suppression, as a function of substrate and resist thickness, will be documented. The Deep-UV resist/top ARC application will be optimized, as well, to maximize throughput.
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 AZ<SUP>TM</SUP> BARLi<SUP>TM</SUP> anti-reflective coating, to the recently introduced PGME/Ethyl Lactate based AZ<SUP>TM</SUP> BARLi<SUP>TM</SUP> 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.