Magnetolithography (ML) is a photoresist-less and photomaskless lithography method for patterning wafer surfaces.
[2] The fabrication of the magnetic masks involves the use of conventional photolithography and photoresist however.
[2] The second component of the process is ferromagnetic nanoparticles (analogous to the photoresist in photolithography, e.g. cobalt nanoparticles) that are assembled over the substrate according to the field induced by the mask which blocks its areas from reach of etchants or depositing materials (e.g. dopants or metallic layers).
After the adsorption of the reacting agent, the nanoparticles are removed, resulting in a negatively patterned substrate.
ML is also a backside lithography, which has the advantage of ease in producing multilayer with high accuracy of alignment and with the same efficiency for all layers.