Substitution of N-Methyl-2-pyrrolidone (NMP) for Semiconductor Technologies

Abstract:
N-Methyl-2-pyrrolidone (NMP) is a commonly used solvent in the semiconductor industry and plays an important role due to its excellent properties for structuring and cleaning semiconductor components. However, since 2020, the use of NMP has been subject to strict restrictions under Annex XVII[1] of the REACH Regulation, as it is classified as reproduction-toxic and poses potential risks for pregnant women and their fetus in the womb. A rising awareness of toxic materials in semiconductor manufacturing like NMP has led to the desire to substitute those. As part of a project, specific requirements for potential alternatives to NMP were systematically evaluated. In the subsequent testing phase, various products were thoroughly investigated. A product based on dimethyl sulfoxide (DMSO) was showing especially promising results. After one optimization cycle the targeted substitute showed excellent cleaning results. This product therefore has the potential to successfully replace both the established photoresist removal process and the lift-off process at Fraunhofer Institute of Photonic Microsystems (IPMS).