8. Removal

Removal

For the removal of softbaked resist films, polar solvents like e.g. the thinner AR 300-12 and remover AR 600-70 are suitable.

For the wet chemical stripping of tempered resist films, the organic, highly versatile removers AR 300-70, AR 300-72 and AR 300-76 are available which may be heated to 80 °C to reduce the dissolution time. Due to a classification of the raw material NEP (Ar 300-70 and -72) as toxic for reproduction, Allresist strongly recommends to use the newly introduced, less harmful remover AR 300-76 which is equivalent with respect to its dissolving power.

Remover AR 300-73 which was designed for special resists may be heated to 50 °C, does however attack aluminium surfaces.

Remover AR 600-71 which is already highly efficient at room temperature is particularly suitable for customers who are able to use removers with low flash point. 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 oxidising acid mixtures (piranha, nitrohydrochloric acid, nitric acid and others) may be applied in wet chemical removal procedures.