2. negative photoresist
Negative photoresists like AR-N 4200, 4300, 4400 are composed of novolacs and bisazides (4200, no CAR) or novolacs, acid generators and amine components (4300, 4400, CAR) dissolved in solvents like e.g. methoxypropyl acetate (PGMEA).
After exposure and subsequent tempering step, the com- position of CAR leads to a crosslinking of the exposed negative-tone resist film. Irradiated areas are consequent- ly rendered insoluble and remain after development, while unexposed areas are still soluble and are dissolved by the developer.