Nanocontact printing of Au nanoarray onto atomically stepped ultrasmooth polymer sheets

Large area Au nanoparticle arrays of dots or meshes were produced onto 0.3-nm-high stepped ultrasmooth poly(methyl methacrylate) (PMMA) sheets by applying a nanocontact-printing technique using a Au-film-coated pillar or mesh molds. The ultrasmooth PMMA sheets were fabricated by thermal nanoimprinting using the atomically stepped sapphire templates. The partial Au ultrathin layer near the protruding area of the mold was adhered onto the PMMA sheet under imprinting conditions (loading of 0.4-2 MPa at 80 °C for 300 s).