“…To overcome the remaining difficulties, we have proposed and demonstrated the creation of well-defined 3D structures by the combination of dry and wet etching processes, and the growth of epitaxial films on the side and facet surfaces of atomically constructed 3D Si templates. ,− The key advantage is a complete shift of the material growth direction from the normal c -axis on a 2D planar substrate toward flexible omnidirectional axes on a 3D patterned substrate with arbitrarily oriented planes. Reconstructed 3D Si surfaces support the epitaxial growth of target materials without misalignment or deformation, similar to the growth of thin films on 2D planar surfaces. ,,, …”