Interferometrically defined 3D photoresist scaffolds are formed through a series of three successive two-beam
interference exposures, a post exposure bake and development. Heating the resist scaffold in a reducing atmosphere to >
1000 °C, results in the conversion of the resist structure into a carbon scaffold through pyrolysis, resulting in a 3D sp3-
bonded glassy carbon scaffold which maintains the same in-plane morphology as the resist despite significant shrinkage.
The carbon scaffolds are readily modified using a variety of deposition methods such as electrochemical, sputtering and
CVD/ALD. Remarkably, sputtering metal into scaffolds with ~ 5 unit cells tall results in conformal coating of the
scaffold with the metal. When the metal is a transition metal such as nickel, the scaffold can be re-annealed, during
which time the carbon diffuses through the nickel, emerging on the exterior of the nickel as sp2-bonded carbon, termed
3D graphene. This paper details the fabrication, characterization and some potential applications for these structures.
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