Selective-Filling Mold for Residual-Layer-Free Patterning of 3D Microstructures

Abstract

We demonstrate a novel selective-filling mold containing physicochemically heterogeneous surfaces to achieve residual-layer-free patterning. Fabricated by femtolaser machining, the mold has hydrophilic surfaces in the concavity and hydrophobic surfaces on the protrusion. The experiments show that, after ink coating, the ink can wet and spread in concavity while dewets and splitted on protrusion, thus isolated ink filaments were finally formed in the concavity and separated by the dry protrusions. Without forming a residual layer, this technique offers an alternative method to fabricate isolated three-dimensional (3D) microstructures. It can be also used for large-area roll-to-roll fabrication of flexible electronics.

Keywords:

• Flexible electronics
• Microtransfer molding (µTM)
• Patterning without residual layer
• Physicochemically heterogeneous surfaces
• Selective filling

ACKNOWLEDGMENT

This work was supported by National Basic Research Program of China (Grant No. 2009CB724202) and the Major Special Projects of Ministry of Science and Technology of China (Grant No. 2011ZX04014-071). The authors gratefully acknowledge Dr. M. Egilmez for the kindly discussion.