The authors present a polymethyl methacrylate(PMMA)-based,reusable microsphere mask used in the laser sub-wavelength photolithography.In order to overcome the diffraction limit to achieve nano-structuring using l-|im ...The authors present a polymethyl methacrylate(PMMA)-based,reusable microsphere mask used in the laser sub-wavelength photolithography.In order to overcome the diffraction limit to achieve nano-structuring using l-|im laser wavelength,the photolithography technique was conventionally characterized by applying a one-off monolayer of silica microspheres serving as Mie scatterers.Addressing the major limitation of this technique,which was that the monolayer of microspheres must be prepared on the sample surface prior to fabrication,the proposed hot press approach could firmly fuse the 1silica microspheres to the PMMA base without the use of adhesives.The PMMA-based microsphere mask could hence reduce the amount of work for the monolayer preparation and was proven reusable for at least 20 times without damage to top or bottom surfaces.Using the mask,dimples that were 0.7 pm in diameter and 40 nm in depth were produced on tool steel by a single pulse of picosecond laser irradiation.展开更多
基金a core-funded project(No.C16-M-034)of SIMTech,A*STAR Research Entities.
文摘The authors present a polymethyl methacrylate(PMMA)-based,reusable microsphere mask used in the laser sub-wavelength photolithography.In order to overcome the diffraction limit to achieve nano-structuring using l-|im laser wavelength,the photolithography technique was conventionally characterized by applying a one-off monolayer of silica microspheres serving as Mie scatterers.Addressing the major limitation of this technique,which was that the monolayer of microspheres must be prepared on the sample surface prior to fabrication,the proposed hot press approach could firmly fuse the 1silica microspheres to the PMMA base without the use of adhesives.The PMMA-based microsphere mask could hence reduce the amount of work for the monolayer preparation and was proven reusable for at least 20 times without damage to top or bottom surfaces.Using the mask,dimples that were 0.7 pm in diameter and 40 nm in depth were produced on tool steel by a single pulse of picosecond laser irradiation.
