The mask aligner is a system used for the fabrication of micro/nano-structured surfaces by the UV irradiation of a substrate coated with photosensitive resist through a photomask reporting the desired drawing. Almost any microscale device or structure requires more than one photomask step. The job of the contact aligner is to allow its user to align features on a substrate to features on a photomask, and allows the production of sophisticated devices involving ten or more of these alignment steps.

The EVG 620 mask aligner includes all the tools able to control the entire micro fabrication process, from the wafer loading to the exposure, thanks to the control of the wafer position in relation to the mask (photolithography) or the stamp (UV-NIL and u-CP) and the exposure dose of the coated substrate through the mask. The system is able to generate structures with micrometric resolution through the photolithography process, to have alignment accuracy under 1 μm and to generate the UV-NIL and µ-CP stamps with an UV-NIL resolution up to 50 nm.