Elisa Riedo (left) and doctoral student Xiangyu Liu (right) fabricate high-quality 2D chips using the thermal scanning probe lithography process they invented. Photo: NYU Tandon.An international team of researchers has reported a breakthrough in fabricating atom-thin processors. Their discovery could have far-reaching impacts on nanoscale chip production and in labs across the globe where scientists are exploring two-dimensional (2D) materials for ever-smaller and faster semiconductors.
The researchers, headed by Elisa Riedo, professor of chemical and biomolecular engineering at New York University (NYU) Tandon School of Engineering, outlined their research results in a paper in Nature Electronics.
They demonstrated that lithography using a probe heated above 100°C outperformed standard methods for fabricating metal electrodes on 2D semiconductors such as molybdenum disulfide (MoS2). Such transitional metals are among the materials that scientists believe may supplant silicon to create atomically small chips. The team's new fabrication method – called thermal scanning probe lithography (t-SPL) – offers a number of advantages over today's electron beam lithography (EBL).
First, thermal lithography significantly improves the quality of the 2D transistors by offsetting the Schottky barrier, which hampers the flow of electrons at the intersection of the metal electrodes and 2D substrate. Unlike EBL, thermal lithography also allows chip designers to easily image the 2D semiconductor and then pattern the electrodes where desired.
In addition, t-SPL fabrication systems promise significant initial savings, as well as lower operational costs: They dramatically reduce power consumption by operating in ambient conditions, eliminating the need to produce high-energy electrons and to generate an ultra-high vacuum. Finally, this thermal fabrication method can be easily scaled up for industrial production by using parallel thermal probes.
Riedo expressed hope that t-SPL will take most fabrication out of scarce clean rooms – where researchers must compete for time on the expensive equipment – and into individual laboratories, where they might rapidly advance materials science and chip design. The precedent of 3D printers is an apt analogy: someday these t-SPL tools with sub-10nm resolution, running on standard 120-volt power in ambient conditions, could become similarly ubiquitous in research labs.
This story is adapted from material from NYU Tandon School of Engineering, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.