Liquid crystal device with 50 nm nanogroove structure fabricated by nanoimprint lithography

We have investigated the alignment of nematic liquid crystals (NLCs) using 50 nm ultrafine nanogrooves fabricated by electron-beam (EB) lithography and nanoimprint lithography. To improve the wettability of NLCs, silicon dioxide was sputtered onto the NLCs after nanogroove fabrication. The azimuthal and polar anchoring energies obtained were 9.4×10−5 J/m2 and 3.6×10−4 J/m2, respectively. From the electro-optical characteristic of a twisted nematic (TN) liquid crystal (LC) cell, the contrast ratio of the TN cell was found to be 44:1, which is a relatively low value because of the misalignment of the EB exposure. However, a steeper and common threshold voltage was obtained for the TN LC cell.

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