Researcher Develops New Nanowire Architecture Improving Miniaturization

EPFL researcher Valerio Piazza works in the Laboratory of Semiconductor Materials and focuses his research on semiconductors at a nanoscale. He specifically focuses on nanowires and nanostructures built using semiconducting materials. The goal of the research is to improve transistors beyond the current saturation point.

Transistors are critical components for modern devices ranging from cars to smartphones and kitchen appliances, among other items. The miniaturization of transistors is reaching the limit due to designs that are near saturation. Major challenges, according to Piazza, are in processing power related to overcoming the saturation point.

He believes we can overcome current saturation using nanowires and other types of nanostructures. Current improvements are coming from advancements in microfabrication methods allowing engineers to develop compact and sophisticated electronic devices. As the size of transistors is reduced, more can be fitted on a circuit improving its processing power.

How small electronic devices can go is limited by the size of the transistor. Piazza has worked to develop new types of transistors based on nanowires to be used in quantum computers. Quantum computers rely on fundamental elements known as a qubit, the smallest unit of memory. That submicron level is where Piazza focuses his research.

The wires being created in the lab are made of atoms from groups III and V of the periodic table, including gallium, aluminum, indium, nitrogen, phosphorus, and arsenic. Transistors used in devices today measure around 10nm, and the horizontal nanowires created in the lab are the same size but promise improved electrical performance depending on crystal quality. The method used by the researcher etches nanoconductors on a substrate surface to create different patterns allowing the testing of various structures for performance. The research is currently focusing on identifying factors that could improve the process.