Development of Low Reflectivity and High Resolution Negative-tone Photoresist

Abstract

The film patterned by the resin Black Matrix (BM) photoresist, which has two features, the lower reflectivity and low stress on environment of a processing developer than the chromium oxide (CrO) photoresist, is applied to the color filter (CF) in the Liquid Crystal Display (LCD). However, the new panel technology, that is required more lower environmental impact, needs lower reflectivity and narrower negative-tone pattern for the resin BM resist in recent years. We investigated the lower reflectivity resin BM resist film with the mill base comprised of the pigment alloyed silver and tin. The thermo gravimetric analysis (TGA) indicated a significant difference on a surface roughness (Ra) measured on an atomic forced microscope (AFM). Moreover, we observed a contact angle of 2-methoxy-1-methyl acetate (PGMEA) on the film with fluorin-cotaning polymer after post-bake at 220°C. From these results, we concluded that the resin BM resist film comprised of the Ag-Sn mill base make lower reflective and narrower negative-tone pattern.