Fabrication of nano-structures using inverse-μCP technique with a flat PDMS stamp

Here, a new technology for uniform nano-patterning in a wide area is introduced. A μCP technique is applied in the opposite way of a traditional method. Using a flat PDMS stamp, sub-mm scale dot features of alkanethiol SAM are patterned onto rigid tips of micro Si structures, which deforms much less than those of PDMS structures. In order to minimize the diffusion of SAM ink in μCp process, the position of a stamp and a substrate is reversely changed, i.e., the Si substrate with micro structures is stamped onto the flat PDMS stamp which is placed on the bottom. Consequently, millions of nano dot features are uniformly patterned on the top of Si structures in a wide area (12 mm × 12 mm). As one application, millions of uniform nano-needles array is fabricated in a large area using a nano-scale metal mask fabricated by inverse-μCP. Besides, this inverse-μCP technique will show another possibility to the nano-fabrication for bio-MEMS technology.