How did Donald Eigler use xenon atoms to spell IBM?

In 1990, Donald Eigler demonstrated the precision of the scanning tunneling microscope by using it to manipulate individual atoms. While the instrument is primarily used for imaging, Eigler utilized the strong electric field between the probe tip and a sample surface to move atoms.

By applying a slight bias voltage to the probe tip, he caused specific xenon atoms to adhere to the tip, allowing him to move them across a nickel surface and release them at precise locations. Through this process, he arranged 35 xenon atoms to spell out the logo of his company, IBM. This achievement served as a landmark demonstration of the ability to construct well-defined nanostructures at the atomic level.12