By Melbourne Centre for Nanofabrication
Photolithography is a process used to transfer a pattern from a mask to a photosensitive resist-coated substrate. The photoresist is then developed in a solution to remove the unwanted material, after which the substrate can move onto the next process such as metal deposition or etching. Photolithography is central to most micro- and nanofabrication applications including microfluidics and cantilever fabrication. The minimum feature sized achieved at MCN using mask lithography is 1µm with a subsequent metal lift-off process. MCN features four photolithography tools – the EVG 6200 Mask Aligner, the SUSS MA6, ABM UV Flood Light Source and the PhableR-100C. The EVG6200 and SUSS MA6 allow for aligning multi layer features using multiple masks. This means that multiple layers can be built up on a single device by using appropriate alignment markers in the mask design. The ABM UV Flood Light Source allows for fast patterning at a lower resolution. The PhableR-100C uses DUV for patterning at high resolution below 300nm pitch and exposures are non-contact, protecting wafers and masks from physical contact and contamination.
