Photosensitive polyetherimide (Ultem) based on reaction development patterning (RDP)

Abstract

Photosensitive polyetherimide (PEI) consisting of non-photosensitive PEI (Ultem®) and photosensitive diazonaphthoquinone (DNQ) compounds gave positive-tone behavior by UV irradiation, followed by development in solution including ethanolamine. The SEM of the resultant images showed fine patterns with 10-15 μm film thickness. GPC and 1H-NMR measurements that can give information on the structure of dissolved components in the irradiated region were carried out in order to clarify the mechanism of pattern formation. The imaging of photosensitive PEI is based on reaction development patterning (RDP), where the amine causes main-chain scission directly related to the pattern formation in development step to form low molecular weight amidized products.