The exposed area as a result of photochemical reactions will be able to stay in the county Movies polymer glue patterned photoresist is a negative photoresist. Negative photoresist polyimide three categories: esters, ionic crosslinking can be carried out and the light of a polyimide type.
Ester type photosensitive polyimide
Ester type polyimide photoresist is to Rubner methods developed on the basis of, in fact, just as a photoresist photosensitive polyimide precursor. Dianhydride with an alcohol and the photosensitive reaction group-diethyl ester, to obtain a photosensitive polyamide resin reacted with a diamine.
Ionic negative photosensitive polyimide
Ionic photosensitive polyimide is polyamic acid and tertiary amine salt with photosensitive groups formed after exposure, between molecules produce "ionic bond - covalent bond - ionic bond" in the form of cross-linking bridge in order to achieve photolithographic patterning.