The main purpose of the laser lithography is to expose patterns in photoresist that has been spun on a substrate such as glass or a semiconducting wafer. The instrument is “maskless” in that no prefabricated masks are necessary; instead, the resist is exposed by scanning a submicron UV laser spot over the substrate surface while turning the laser on and off to expose the desired pattern.
The laser lithography laser writer is a direct-write (maskless) lithography system produced by Microtech s.r.l. of Italy. The tool contains two laser diode assemblies for the efficient exposure of both positive and negative photoresists. The five objective lenses allow for a broad range of high resolution and high-speed writing applications. In addition to traditional binary patterns, the system supports grayscale patterning with 256 level control. A 10 nm interferometric nanopositioning stage allows for 0.8 µm patterning over the full 100 x 100 mm working area of the stage.