Easy Orientation of Diblock Copolymers on Self-Assembled Monolayers Using UV Irradiation

• DOI: 10.1021/ma9021357
• Publication Date: 2009-11-16T13:54:01Z
• Authors: Pang-Hung Liu; Pascal Thébault; Patrick Guenoun; Jean Daillant
• Keywords: Soft Condensed Matter (cond-mat.soft); FOS: Physical sciences; 02 engineering and technology; Condensed Matter - Soft Condensed Matter; 0210 nano-technology; 01 natural sciences; 0104 chemical sciences

3 figures, 1 table<br/>A simple method based on UV/ozone treatment is proposed to control the surface energy of dense grafted silane layers for orientating block copolymer mesophases. Our method allows one to tune the surface energy down to a fraction of a mN/m. We show that related to the surface, perpendicular orientation of a lamellar phase of a PS-PMMA diblock copolymer (neutral surface) is obtained for a critical surface energy of 23.9-25.7 mN/m. Perpendicular cylinders are obtained for 24.6 mN/m and parallel cylinders for 26.8 mN/m.<br/>