Diamond nanopatterns fabricated by room-temperature nanoimprinting technology with diamond molds using polysiloxane

Fabrication of diamond nanopatterns in room-temperature (RT) nanoimprint lithography (NIL) with chemical vapor deposited (CVD) diamond molds using polysiloxane as RT-imprint resist material was investigated. The diamond molds of a convex lattice with 1 μm line-width and 5 μm pitch, and a cylinder dot with 200 nm diameter and 1 μm pitch which has a height of 1 μm using RT-NIL process were fabricated with Bi₄Ti₃O₁₂ octylate (oxide) mask in electron beam lithography technology. The maximum radio frequency (RF) oxygen plasma-etching selectivity (diamond/polysiloxane) of 19 was obtained under the conditions of RF power of 100 W, oxygen gas flow rate of 10 sccm and background gas pressure of 30 Pa. It was found that the optimum imprinting pressure and its depth obtained after the press duration of 10 min were 0.8 MPa and about 0.5 μm, respectively. The resulting diamond nanopatterns of a concave lattice with 1 μm line-width and 5 μm pitch, and a concave cylinder dot with 200 nm diameter and 1 μm pitch which have a height of 1 μm after RF oxygen plasma-etching (100W, 10 sccm, 30 Pa, 40 min) were fabricated with diamond mold RT-NIL using polysiloxane.