Molecules can be designed with high precision. This makes their properties tunable for use in next-generation computing, sensing, optical systems, and quantum technologies. However, integrating molecules into functional devices at useful volumes has remained difficult. Conventional semiconductor manufacturing, the set of industrial steps used to produce computer chips, relies on harsh chemicals and processes that readily damage molecular layers and reduce device performance.
Researchers at MIT developed a scalable fabrication approach that avoids this damage. They first create the main device parts with ordinary semiconductor methods. Only afterward do they introduce the molecules. Nanoscale surface forces then cause the structure to reshape itself and form the completed device. The process was shown to work by producing more than one thousand devices that contain molecular layers thinner than one nanometer.
How the assembly occurs
The researchers first built a scaffold containing two metal electrodes separated by a precisely controlled gap. They then deposited the molecular layer onto the electrode surfaces. As the liquid that carried the molecules evaporated, capillary forces gently drew the electrodes together. Capillary forces are the attractions that pull liquids into narrow spaces, the same effect that helps plants draw water upward through their stems. Once the electrodes contacted the molecules, van der Waals forces held them in a stable position. Van der Waals forces are weak attractions that act between nearby surfaces or molecules.
The resulting electrical contacts remained intact and free of damage. On average 96 percent of the fabricated devices functioned correctly, and the devices continued to operate after tens of thousands of electrical cycles. The same method also produced interconnected arrays of molecular memory elements, demonstrating that the approach can support circuit-level systems rather than isolated components. The technique is expected to extend to other nanoscale materials and device designs, opening a practical route to more complex molecular electronics.
This research is published in Nature Nanotechnology.