Resist of the month January: SU 8 alternative – negative photoresist Atlas 46
The outstanding properties of SU-8 are well known to all users of microsystem technologies. Allresists new negative resist Atlas 46 S (solid) can easily be processed with high reproducibility of all properties and with high restistance of resist structures to all commonly used solvents. Atlas 46 S is thus perfectly suitable for all applications in which the layer is intended to remain permanently and resistively on the substrate.
Resist Atlas 46 R (removing) contains specific additives which reduce the degree of cross-linking. Structures thus can be removed again with commercial removers which extends the range of potential applications in photolithography. The resist is in addition sutiable for galvanic applications since it can also easily be removed after metallisation.
With a third version of Atlas 46 which can be exposed at a wavelength of > g-line (436 nm), a selective build-up of multilayers is possible. Three-dimensional structures can be generated by combining two different variants: At first, Atlas 46 S is exposed (λ1 < 365 nm) and cross-linked by tempering. Then, SX AR-N 4600-10/10 is coated onto the first resist, exposed (with λ2 > 380 nm), and the double layer is baked again. During development, the non-exposed areas of the top layer and the non-exposed areas of the bottom layer under the second layer are washed out.
Process flow 3D multilayer system Atlas 46
Atlas 46 R 5 µm line & space, structures are easily removable