Scanning probe lithography for nanoimprinting mould fabrication

Abstract

We propose a rational fabrication method for nanoimprinting moulds by scanning probelithography. By wet chemical etching, different kinds of moulds are realized on Si(110) andSi(100) surfaces according to the Si crystalline orientation. The structures have line widthsof about 200 nm with a high aspect ratio. By reactive ion etching, moulds with patterns freefrom the limitation of Si crystalline orientation are also obtained. With closed-loop scancontrol of a scanning probe microscope, the length of patterned lines is more than100 µm by integrating several steps of patterning. The fabrication process is optimized in order toproduce a mould pattern with a line width about 10 nm. The structures on the mould arefurther duplicated into PMMA resists through the nanoimprinting process. The method ofcombining scanning probe lithography with wet chemical etching or reactive ion etching(RIE) provides a resistless route for the fabrication of nanoimprinting moulds.