Autonomous Atom Assembly

NIST logo with cobalt atoms on a copper surface produced in the NIST Nanoscale Physics Facility.
The ripples in the background are due to electrons in the fluid-like layer at the copper surface bouncing off the
cobalt atoms, much like the patterns produced when pebbles are dropped in a pond.

The ability to use an STM to move and position atoms with lattice site precision provides us with a quantum workbench to study the effects of quantum confinement and the electronic structure of perfect nanostructures. So far, atomic manipulation has been performed manually, or with rudimentary computer assistance. We are working to extend this capability significantly by developing an Autonomous Atom Assembler (AAA). An autonomous atom assembler is an instrument capable of assembling a desired nanostructure from an unknown random collection of atoms without human intervention. Our instrument is based on our low temperature STM system, with hardware and software extensions. In operation, a dilute coverage of adsorbate atoms is deposited on a clean, flat substrate. The AAA then instructs the STM to image the random adsorbate pattern, identifies the position of each adsorbate atom relative to the substrate lattice, and plans a series of moves to place the available atoms at positions specified in a previously entered diagram. The plan minimizes construction time, follows a set of extensible rules, and allows for error correction. The AAA then instructs the STM to execute the plan and, upon completion, provide an image of the final assembled nanostructure. In our initial trials, Co atoms were deposited at sub-monolayer coverage on a Cu(111) at 7K in UHV and subsequent STM measurements were performed at a 4.3 K sample temperature. We are now in the process of testing the AAA on simple confinement structures consisting of tens of atoms. We plan to extend it to large numbers of atoms, large confinement structures, and arrays of nanostructures that differ only slightly to allow a combinatorial approach to nanostructure characterization. For insight into exactly how atoms move on the surface, see Atom Dynamics in Atom Manipulation.

Nanoscale Physics Facility 


Joseph A. Stroscio 
Robert J. Celotta 
Steven R. Blankenship
Frank M. Hess 


Stephen Balakirsky  - NIST(MEL)


Aaron Fein  - NIST (PL)


John Cugini - NIST (retired)
Alberto Lacaze - NIST (retired)

Supported in part by the Office of Naval Research

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Online: July 2004
Last Updated: February 2008

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