Because of the tighter linewidth control requirements for 0.35 micrometer gate, adequate critical dimension control could not be achieved with a single layer photoresist. A top-side anti-reflective coating (TARC) was found to have limited line width control benefit and did not effectively reduce reflective notching. Since TARC or a single layer resist system could not adequately control linewidth variation a joint project between a bottom-side anti-reflective coating (BARC) supplier and user was undertaken to develop a new generation i-line material to address the gate linewidth control and reflective notching issues seen at 0.35 micrometer design rules. The newly developed BARC has improved optical properties compared to previous i-line compatible material as well as improved manufacturability. The new BARC is spin cup compatible with photoresist, is compatible with standard edge bead removal chemicals, has low defect density as spun, and is room temperature stable. Also, the spun material is resistant to chemical intermixing with a variety of resists having various safe solvent systems. This leads to excellent resist profiles. The joint development approach allowed quick selection of the best BARC material, optimization of the material's formulation and also timely verification of the performance for an actual 0.35 micrometer application. Prolith/2TM reflectivity simulations were used to predict and then verify optimum BARC process setup. Swing curve simulations were compared to actual product intradie linewidth variations for single layer resist, TARC, and BARC processes. Profiles for several resists on different BARC thicknesses were studied for image quality, resolution, and linewidth control.