Micro/nano glass press molding using silicon carbide molds fabricated by silicon lost molding

Silicon carbide (SiC) molds for micro/nano glass press molding at high temperature were fabricated from a silicon mold. The silicon molds with the features of micro-optics were fabricated by photolithography and etching and then SiC was deposited on the silicon mold. After the SiC surface was polished to a mirror surface, a SiC ceramic block was bonded with the SiC film using a nickel interlayer at 900 °C. Finally, the silicon mold was etched away using the mixture of nitric acid and hydrofluoric acid. The surface roughness of the SiC mold is 1.2 nm Ra, which is almost identical with that of the silicon mold. This suggests that this process is promising to make the SiC mold for optical uses. Glass press molding was preliminarily performed at 400 °C using the SiC mold coated with diamond-like carbon (DLC). Although some parts of the SiC film were peeled off due to poor SiC-SiC bonding quality, the features on the SiC mold were well transferred to the glass.