How can resist coatings be removed again?

For the removal of softbaked coatings, polar solvents such as e.g. the respective resist thinner AR 300-12 (methoxy propyl acetate = PGMEA) and the remover AR 600-70 (acetone-based) may be used. Remover AR 600-70 is most commonly used.

For the wet-chemical removal of photoresist layers high-baked up to 180 °C, Allresist recommends the organic all-round mover AR 300-76 which can be heated to 80 °C to reduce the dissolution time. Furthermore suitable are the organic removers AR 300-70 and AR 300-72 which however contain NEP as main component which was classified as toxic for reproduction.

For photoresist films baked up to 170 °C, also the aqueous-alkaline remover AR 300-73 is well suited which can be heated up to 50 °C, but this remover attacks aluminium surfaces.

For photoresist films which were tempered up to 170 °C, we recommend remover AR 600-71 which works very efficiently already at room temperature. This remover is especially intended for customers who use removers with low flash point.

~ details see product information remover

In semiconductor industries, the removal (stripping) is mostly performed by ashing in a plasma asher. The O₂-plasma generated by microwave excitation is used for an isotropic etching of the photoresist. But also oxidizing acid mixtures (piranha, nitrohydrochloric acid, nitric acid and others) may be applied in wet chemical removal procedures.