Electronic components with the size of an atom are nothing new, but until now they only existed in the laboratory. But now a new center for single atom electronics could shorten the long journey into the factories.
The electronics industry left the micrometer range behind ages ago and is now producing nanometer-size electronic components. But because there is no such thing as “too small”, now we regularly hear the world’s laboratories talking about “the smallest ODER in the world” made of just a few magnetic atoms or the “first atomic transistor in the world”. The latter example shows how protracted research in these scale ranges can be. It comes from the year 2004. That is when Professor Dr. Thomas Schimmel from the Karlsruhe Research Centre introduced a single-atom transistor consisting of a single atom of silver.
The component works like a switch that opens and closes an electric circuit. On two metal electrodes, between which a tiny gap interrupts the electric circuit, silver is discharged until a single silver atom connects the two poles. The circuit closes and current flows. If controlled by a third, independent electrode, the atom can now be opened and closed. Applying an external control voltage would make it possible to switch the current between the electrodes on and off like a “big” transistor. In the final analysis, all computer and information technology is based on this simple mechanism.
Because the “bridge atom” is the only moving part in the single-atom transistor, it could in principle be used at extremely high frequencies. In addition, just a few millivolts are needed for operation, which would reduce energy consumption considerably. Finally, it was hoped at the time that single-atom electronics would lead to the development of custom quantum electronic systems (quantum system engineering) at room temperature.
Single-atom electronics for manufacturing
Now, thirteen years later, this basic research is supposed to culminate in industrial prototypes and marketable products. To that end, the Karlsruhe Institute for Technology (KIT) and ETH Zurich are building a joint center for single-atom electronics and photonics. The venture was made possible by an endowment from the Swiss Werner Siemens Foundation worth 10.5 million euros.
Research focuses on integrated circuits whose components function at the level of single atoms but can also be integrated into existing industrial CMOS technology. In the next step, scientists will develop new components for the logic and memory modules based on the prototypes. That will be followed by the first simple chips in a new generation of atomic-scale components. That will make it possible to reduce sizes by a factor of 100 to 1,000 and energy consumption by the same order of magnitude compared to today’s metal-oxide semiconductors (CMOS).