Three-dimensional metal patterning over nanostructures by reversal imprint

Reversal imprint is used to pattern three-dimensional (3D) metal structures over substrates with complex topography. Metal films are deposited onto SU-8 polymer layers on glass molds, lithographically patterned, and transferred to Si or SU-8 substrates with nanosctructured surfaces by reversal imprint at 5MPa, 80°C, and 1s of UV exposure. The transfer of metal patterns of 50∕20nm thick Au∕Ti and 0.5μm thick Al as well as 3D Al structures have been demonstrated.