Newly developed nanowelding techniques are being used in the world’s smallest construction site, located in a Swiss laboratory.

The researchers behind the techniques say they can be used to assemble electronic components at smaller scales than have ever been possible.

One technique, called "nanorobotic" spot welding, uses molten copper to join up objects in the same way that a human electrician might use solder.
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"We position a 50-nanometre-wide carbon nanotube filled with copper inside a nanorobotic manipulator, and run a small voltage through it to melt the copper," explains [Lixin] Dong [of the Institute of Robotics and Intelligent Systems, Zurich, Switzerland]. In experiments the researchers positioned the manipulator so the melting metal connected one carbon nanotube to another.

Nano-scalpels for cutting living cells have already been made.  The scalpels, measuring 10 nanometres by 20 nanometres, are only a few nanometres in thickness.

h/t: Faith-Science News