Lithographic Process Optimization for Next-Generation Advanced Packaging Influenced by Wafer Topography and Reticle Stitching

The rapid advancement of AI, optics, and quantum technologies is driving demand for large-area devices, such as high-performance interposers. These approaches often require reticle stitching on wafers that exhibit significant warpage and surface topography. This study evaluates the impact of wafer warpage and topography on the lithographic performance of ArF, KrF, and i-Line systems in 2.5D interposer and 3D advanced packaging applications, with a focus on stitched versus non-stitched features. We employ a combined experimental and computational methodology that shows wafer flatness and stitching accuracy can limit the efficacy of more advanced lithography technologies. ArF lithography offers clear advantages in pitch scaling but demands much tighter control over topography and stitching. KrF and i-Line systems provide more robust performance under relaxed process conditions, making them suitable and more cost efficient for applications with less stringent patterning needs. Ultimately, the lithography choice must balance technical capability with manufacturability and cost.