Silicon microchips and 2D materials together at last

"In the future, most microchips will exploit some of the many outstanding electronic and thermal properties of these materials."Mario Lanza, KAUST

Two-dimensional (2D) materials are expected to revolutionize the semiconductor industry. However, despite multiple studies that have reported prototype devices with promising properties for sensing and driving electrical current, the technology-readiness level of these devices is still very low. This is because the studies have mostly used synthesis and processing methods that are incompatible with industry, created the large devices on unfunctional substrates, and presented poor variability and yield.

Now, a team of scientists at King Abdullah University of Science and Technology (KAUST) in Saudi Arabia, led by Mario Lanza, associate professor of materials science and engineering, has successfully integrated 2D materials on silicon microchips, and achieved excellent integration density, electronic performance and yield. The scientists report their advance in a paper in Nature.

"In the future, most microchips will exploit some of the many outstanding electronic and thermal properties of these materials," said Lanza.

In particular, Lanza’s team combined a 2D insulating material called multilayer hexagonal boron nitride (about 6nm thick) with microchips containing silicon transistors of complementary metal-oxide-semiconductor (CMOS) technology. This type of transistor technology is present in every electronic product we use today, including phones, computers, automobiles, medical machines and household appliances.

The resulting hybrid 2D/CMOS microchips exhibit high durability and special electronic properties that allow the fabrication of artificial neural networks with very low power consumption. This is because they can successfully compute spiking neural networks – electrical stresses applied over a very short time – which are a key component of current artificial intelligence systems. Most current devices are not suitable for implementing this type of neural network, spurring an effort to find new approaches.

This research has attracted the interest of leading semiconductor companies such as Taiwan Semiconductor Manufacturing Corporation (TSMC) and Advanced Semiconductor Materials Lithography (ASML) and could help other companies reduce processing costs and energy. Most companies in the field of microchip manufacturing and artificial intelligence are aiming to create new hardware that reduces data processing time and energy consumption, but have not yet found a suitable device.

IBM has already attempted to integrate graphene into transistors for radio-frequency applications, but these devices were not able to store or process information. This is in contrast to the 2D/CMOS devices created by Lanza's team, which measure only 260nm and could be made much smaller if more advanced microchips were available.

This story is adapted from material from KAUST, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.