High Performance Bulk and POU Filtration of EUV Lithography Materials

Abstract

To comply with defect specification, Extreme Ultra-Violet (EUV) lithography necessitates performance improvement for both bulk and point-of-use (POU) filters. In this study, the data represent novel polyethylene and nylon filters for a variety of bulk and POU applications, specifically designed to: i) dramatically reduce differential pressure while achieving excellent retention, and ii) provide outstanding cleanliness for EUV grade application. Each filter was assessed by differential pressure (dP), liquid particle counter (LPC), GC-MS, and ICP-MS measurements. Finally, defect data were obtained from blanket and pattern wafers, prepared at the imec EUV cluster comprised of TEL Cleantrack LITHIUS Pro-Z and ASML NXE:3400B with a 16nm L/S test vehicle and characterized by a KLA-2935 and an eDR-7380 tools.