February 8, 2021
1:00-2:00 p.m.
James Gimzewski
UCLA
ABSTRACT: APM will enable a paradigm shift in 21st century manufacturing practices in which every single atom in an electronic chip, device or machine can be placed in an exact and predefined position in three-dimensions. The first stage toward APM requires absolute control over the structure and chemistry of the SPM tip, which serves as the physical workpiece for manufacture. However, previous theoretical and experimental works on atom by atom and molecule by molecule fabrication of precise structures are limited to essentially two-dimensions. In the present work computational efforts, specifically identified reactants have been designed as a first stage and used to selectively extract atoms from the SPM tip, re-shaping it to a predefined crystalline form. Mechanosynthetic APM has utilized chemical systems where thermodynamics drives a series of reactions forward. Defects and randomness in the tip structure will thus be eliminated, allowing the tip to be used in subsequent atomic-scale assembly through the vertical manipulation of molecular feedstocks. Computational modelling has enabled fundamental developments in both tip and surface chemistry to produce surface-bound reactants for re-shaping matter with atomic precision in three dimensions.