Mold Pattern Fabrication by Nanoscratching
Jun Shimizu*, Libo Zhou*, Takeyuki Yamamoto*,
Hirotaka Ojima*, Teppei Onuki*, and Han Huang**
*Department of Intelligent Systems Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi 316-8511, Japan
**School of Mechanical & Mining Engineering, The University of Queensland, Brisbane, QLD 4072, Australia
MEMS technologies for various nano/micro-devices often requires special facilities and complicated,multistage processes. The fabrication cost is thus extremely high. Consequently, alternative solutions have been sought, and NanoImprint Lithography (NIL) is one of the potential solutions. To date, the nano/micromolds for NIL are mainly fabricated using photolithography or focused ion beams. However, such beam methods generally make use of special instruments and require a long time to draw precise patterns. Thus, this study aims to fabricate nanoscale structures on monocrystalline silicon substrates using nanoscratching, which can potentially be used to fabricate nano/micro-molds for NIL. This paper discusses how various nano/micro-scale structures such as lineand-space, single-layer, and multiple-layer structures were fabricated on a silicon substrate using nanoscratching by an atomic force microscope equipped with a sharp probe made of monocrystalline diamond. Subsequent chemical etching was also conducted on the fabricated groove patterns to enlarge the depth of the fabricated groove patterns. The results confirmed that the groove was deepened several times, with only a slight increase in its width. A nanoimprint experiment was also carried out, and the line-and-space patterns were duplicated successfully on a polycarbonate resin film.
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