A new tool allows atomic 3D printing
A new tool now rests in the 3D printing toolbox. The electron beam in a scanning transmission electron microscope has been exquisitely controlled with specially programmed electronics to tunnel into non-crystalline material and construct 3D features that are in perfect alignment with the underlying substrate (i.e., epitaxial). The result is designer materials with desirable structures, such as microchips, or materials with unique properties. Essentially, any shape can be created by exposing patterned areas to higher numbers of electrons than non-patterned areas, resulting in epitaxial 3D features down to 1-2 nanometers — less that the width of a strand of DNA.
Electron microscopes with atomically focused beams, even from older instruments, can easily be transformed from characterization tools to nanoscale fabrication platforms, complementing macroscopic 3D printing. This nanoscale fabrication tool could be used to make integrated circuits and non-equilibrium systems such as strategically concentrated impurities in crystals that lead to unique properties.
3D printing has revolutionized the way we can make and design materials. Now a team led by scientists at Oak Ridge National Laboratory has added another tool to the 3D printing toolbox.