While molecular-size components such as diodes and resistors built from individual atoms have been demonstrated in laboratories worldwide, their exceedingly small size creates some fundamental problems. One is how to solder these tiny components into circuits. Now the National Institute of Standards and Technology (NIST) is offering a patented solution: a molecular soldering iron for researchers who are assembling electronics one atom at a time. "We patented this process because we knew of the need for something like a molecular soldering iron from U.S. researchers," said NIST researcher Chris Zangmeister, who said that NIST is "cooperating with universities and companies like Hewlett-Packard" on the project. The process, co-developed by Zangmeister and fellow NIST researcher Roger van Zee, connects molecular components with copper by selectively coating only the ends that need to be soldered. A layer of molecular components is first assembled with all their ends pointing upward from the substrate. The dangling ends get coated, so that future devices can be soldered into a second layer in a multilayered-chip construction similar to the way silicon chips are built.