Formation of SiO2 Air-Gap Patterns Through scCO2 Infusion of NIL Patterned PHEMA

Using templates generated by nanoimprint lithography, we report the fabrication of SiO2 patterns (∼450 nm) line widths over large active surface areas (14.5 cm2). The process involves the patterning of poly(2-hydroxyethyl methacrylate) (PHEMA) using polycarbonate molds followed by tetrachlorosilane (TCS) vapor cross-linking and supercritical carbon dioxide (scCO2) assisted tetraethylorthosilicate (TEOS) infusion. Uniform SiO2 lines were observed over an area 14.5 cm2, which suggests that this process can be readily scaled.