Point-of-use filtration strategy for negative tone developer in extended immersion and extreme ultraviolet (EUV) lithography

摘要

Negative tone development (NTD) has dramatically gained popularity in 193 nm dry and immersion lithography, due to their superior imaging performance. Popular negative tone developers are organic solvents such as n- butyl acetate (n-BA), aliphatic ketones, or high-density alcohols such as Methyl Isobutyl Carbinol (MIBC). In this work, a comparative study between ultra-high molecular weight polyethylene (UPE) and polytetrafluoroethylene (PTFE) POU filtration for n-BA based NTD has been carried out. Results correlate with the occurrence or the mitigation of micro bridges in a 45 nm dense line pattern created through immersion lithography as a function of POU membrane.