Diodes, also known as rectifiers, are a basic component of modern electronics. As we work to create smaller, more powerful and more energy-efficient electronic devices, reducing the size of diodes is a major objective. Recently, a research team from the University of Georgia developed the world’s smallest diode using a single DNA molecule. This diode is so small that it cannot be seen by conventional microscopes.
A diode is an electrical device that allows current to move through it in one direction much more easily than the other. No diode prevents 100% of current flow in one direction while allowing unlimited current in the other direction—in reality, a diode will always allow some current in both the “forward” and “backward” directions. The larger the imbalance favoring the “forward” direction, however, the better diode we have. Diodes are responsible for controlling the current in many common electronic components. Millions of diodes are embedded in a single silicon chip, and to increase the processing power of these chips, the diodes need to be made smaller.
Following a prediction originally made in 1965 by Intel co-founder Gordon Moore, now known as Moore’s law, scientists and engineers have been able to make smaller and smaller computer hardware by doubling the number of electronic components in a silicon chip every 18 months. These improvements in computing power are approaching the physical limits of silicon, however; when silicon components are too small, they will become unstable and their performance unpredictable.
