Performance and characteristics of SiO2 imprint mould fabricated by liquid-phase deposition

Mould fabrication, which is the key factor determining the resolution in nanoimprint lithography, was investigated in this study. Instead of the traditional methods such as electron-beam lithography and ion-beam lithography, a newly-proposed method was selected to fabricate the imprint mould; the plasma ashing technique and liquid-phase deposition (LPD) were used to fabricate the fine patterns in a silicon dioxide (SiO2) mould. The SiO2 mould was pressed into polymethylmethacrylate (PMMA) on a silicon substrate with 4.4 MPa at 190 ∘C. All of the transferred patterns on PMMA had a minimum accuracy of 94.0% with respect to the shape and size of the SiO2 mould. We confirmed that the deposited SiO2 mould was able to imprint nanometer scale patterns with a minimum resolution of 98.9 nm. The adhesion value of 29.4 N and hardness of 8.896 GPa, which were obtained from the as-fabricated mould, remained the same or were slightly increased after imprinting several times. The distinguished characteristics of the LPD- SiO2 mould for nanoimprint lithography were confirmed in this study.