NMP Free Positive Photo Resist Stripping with E-GRADE® MEOX
ABSTACT
Huntsman is committed to delivering solutions that support a more sustainable future. Our technologies help address critical environmental and safety challenges across many industries. This study highlights one such solution that enables the use of safer alternatives to N Methyl 2 pyrrolidone (NMP), advancing both performance and sustainability goals.Growing regulatory concerns over the toxicity of NMP have increased market demands for safer solvent alternatives. Our criteria focused on maintaining or improving solvent properties, enhancing health and safety ratings, and securing reliable domestic sourcing without significant cost impact. To address these evolving requirements, Huntsman collaborated with High Purity Products to develop an effective alternative to NMP based strippers.
Here, we introduce a new NMP-free alternative chemistry—leveraging a blend of solvents developed by Huntsman—that functions as a drop-in replacement compatible with existing wet process tools. Combined with High Purity Products’ semiconductor expertise, this collaboration has produced a breakthrough line of resist-strip chemistries designed to meet rigorous industry standards.
E-GRADE® MEOX is an aprotic solvent with similar solubility parameters to NMP, but it has lower vapor pressure, higher flash point, is not rated as a hazardous air pollutant, and can be recycled and recovered like NMP. Huntsman has evaluated it as an alternative to NMP and have seen that MEOX has comparable, or better, performance to NMP or NMP/amine mixtures in photoresist removal. Photoresists hard baked at 210°C saw greater solvent penetration by MEOX than NMP or DMSO. MEOX was also observed to dissolve a higher weight percent of photoresists which may extend use life.
Many common NMP replacements fail to meet the performance requirements of established processes. Through careful selection of co-solvents it is possible to create a blend that not only replace NMP but also delivers additional performance benefits. This new blend was evaluated in end user fab studies, which demonstrated improved particle removal without negative impacts on photoresist removal.
Huntsman warrants only that its products meet the specifications agreed with the buyer in the sales contract. Typical properties, where stated, are to be considered as representative of current production and should not be treated as specifications.
E-GRADE® MEOX is a registered trademark of Huntsman Corporation or an affiliate thereof in one or more, but not all, countries.
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BIOGRAPHY
Jay Henderson is the Global Marketing Manager for Huntsman's Advanced Technologies group, which supplies products to the semiconductor and lithium-ion battery industries. Prior to his current role, Jay spent 14 years in R&D, focused on small molecule synthesis in a broad range of fields, including molecular electronics, organosulfur-based materials for lithium-ion batteries and supercapacitors, and biodegradable polymers. He holds a Bachelor of Arts in Chemistry from Rice University, a Ph.D. in Materials Chemistry from Cornell, and an M.B.A from the University of Delaware.