Jul 19, 2012
Atomic-scale wires lined up on silicon
Scientists from Zyvex Asia, the A*STAR Institute of Materials Research and Engineering (IMRE) and Zyvex Labs have worked together to develop fabrication technology for realizing manufacturing on the atomic scale. Using a customized ultrahigh-vacuum STM, which was developed in-house and equipped with advanced drift-control, the team has demonstrated the reproducible fabrication of continuous sub-1 nm dangling bond wires and aligned them with atomic precision at room temperature.
As shown in the figure, the sequential controlled patterning of two sub-1 nm dangling bond (DB) wires was performed with atomic precision. The researchers discovered that an optimum set of patterning parameters exists, which enables operators to obtain near-perfect silicon DB lines and align them with near atomic precision in a highly controllable manner.
The group's results indicate that the pattern quality is only weakly dependent on the STM tip apex geometry when the patterning parameters are within the optimum parameter space. This may relax the requirements for atomically reproducible tip apices, which are notoriously difficult to fabricate.
The researchers presented their results in the journal Nanotechnology.
About the author
The study was conducted in a research collaboration involving teams from Zyvex Asia Pte Ltd, A*STAR Institute of Materials Research and Engineering (IMRE) in Singapore and Zyvex Labs LLC in the US, with the goal of developing a novel atomic precision manufacturing technology to build atomically precise products atom by atom. This work was supported by funding from Zyvex Labs LLC (USA) and A*STAR (Singapore). Dr Shi Chen conducted the patterning experiments and is now a research fellow at NTU, Singapore. Dr Hai Xu served as the Zyvex Asia team leader, he built the UHV STM systems, and he has many years of experience in surface science. Dr K E Johnson Goh is the principal investigator for atom technology in IMRE, and has been involved in STM-based device fabrication for more than 10 years. Dr Lerwen Liu is the project manager of Zyvex Asia. Dr John Randall is the president of Zyvex Labs.