Nano-scale optical elements by fine patterning of self-assembled monolayers

2004 Fiscal Year Final Research Report Summary

• Project/Area Number: 14550229
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Intelligent mechanics/Mechanical systems
• Research Institution: Tokyo National College of Technology (2004); The University of Tokyo (2002-2003)
• Principal Investigator: FUKUDA Katsumi Tokyo National College of Technology, Prof., 機械工学科, 教授 (20134471)
• Co-Investigator(Kenkyū-buntansha): SHIIMOYAMA Isao The Univ. of Tokyo, Prof., 大学院・情報理工学系研究科, 教授 (60154332) ; MATSUMOTO Kiyoshi The Univ. of Tokyo, Associate Prof., 大学院・情報理工学系研究科, 助教授 (10282675) ; HOSHINO Kazunori The Univ. of Tokyo, Assistant Prof., 大学院・情報理工学系研究科, 講師 (30361546) ; ICHIKAWA Yasumasa The Univ. of Tokyo, Research Assistant, 大学院・情報理工学系研究科, 助手 (40134473)
• Project Period (FY): 2002 – 2004
• Keywords: self-assembled / monolayers / surface active / patterning / micro contact printing / hydrophilic / hydrophobic / nano-scale optical elements

Research Abstract

This project is on a fabrication method of nano-scale optical elements using micro contact printing (uCP). Alkyl silane molecules were coated on poly(dimethylsyloxane) (PDMS) stamps with nano- to micro-patterns, and transferred the molecules onto a glass wafer to form a self-assembled monolayer (SAM). Then, the molecules were labeled by fluorescent molecules to enhance optical properties. We used PDMS as a material of the stamps. The patterns of the stamps were transferred from silicon molds, which were fabricated with isotropic etching or electron beam (EB) direct lithography.
Firstly, stamps with micro-scale lines and spaces were used to confirm the feasibility of SAM patterning. We coated Aminopropyltriethoxysilane (APTES), which has amino group at its terminal, on the PDMS stamps, and pressed the stamp onto glass wafer. The patterned APTES were labeled by the fluorescent dye molecules (FITC), and observed with fluorescent microscope. The pattern was evaluated by comparing the line width of the stamps and the patterned APTES. For suitable patterning, the pressing time and pressure were found to be 15 seconds and 20 grams, respectively.
Secondly, nano-scale optical elements were fabricated. The FITC itself was used as an optical element. Combining the nano-scale patterning of APTES and the FITC labeling, we successfully achieved to fabricate nano-scale optical element. Using PDMS stamps of an illustration, which was drawn with sub-micron lines, APTES was patterned on a glass wafer. The FITC were bound to the patterned APTES. We successfully observed that the fluorescent molecules were surely patterned along the APTES with nano-order resolution, and confirmed that the fluorescent molecules work as nano-scale optical elements.