Fabrication of Less than 20-nm-Diameter Nanodot Arrays Using Inorganic Electron Beam Resist and Post Exposure Bake
Jun Taniguchi*, Tetsuro Manabe*, and Kiyoshi Ishikawa**
*Department of Applied Electronics, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
**Tokyo Ohka Kogyo Co., Ltd., 1590 Tabata, Samukawa, Koza, Kanagawa 253-0114, Japan
Next-generation NanoImprint Lithography (NIL) includes photolithography and high-voltage-acceleration (>50 kV) Electron-Beam Lithography (EBL) both of which are expensive, which is why Low-Acceleration-Voltage (LAV) EBL has attracted attention. We fabricated nanodot arrays with a diameter of 20 nm or less combining inorganic resist and LAV EBL. Using Post-Exposure Bake (PEB), we reduced dot-array pattern size and conducted Ultra-Violet (UV) NIL using these nanodot molds. The results we obtained using nanodot arrays 10 nm in diameter fabricated by EBL at an acceleration voltage of 4 kV with PEB yielded a checkerboard design 10 nm in diameter spaced at 20 nm intervals using 10 kV EB. This density corresponds to nanodot-arrays of 1 Tb/in2.
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