2D Materials for the Next Generation of Data Processing
In Nature Communications, RWTH professor Max Lemme and colleagues outline the most promising applications of two-dimensional (2D) materials.
"More Moore" and "More than Moore": these are the terms used to describe two of the most important research projects in the semiconductor industry. More Moore is an expression for the efforts to extend "Moore's Law", i.e. the continuous striving to make transistors smaller and to integrate more, smaller and faster transistors on each chip of the next production node. More than Moore instead points to the combination of digital and non-digital functions on the same chip, a trend also known as "CMOS+X" that is becoming increasingly important with the advent of 5G connectivity and applications like the Internet of Things and autonomous driving.
For both of these research projects, 2D materials are an extremely promising platform. Their ultimate thinness, for example, makes them prime candidates to replace silicon as the channel material for nanosheet transistors in future technology nodes, which would enable continued dimensional scaling. In addition, devices based on 2D materials integrate well in principle with standard CMOS technology and can therefore be used to extend the capabilities of silicon chips with additional functions, such as in sensors, photonics or memristive devices for neuromorphic computing. To this end, RWTH scientists Max C. Lemme and Christoph Stampfer with Deji Akinwande (University of Texas, Austin, USA) and Cedric Huyghebaert (IMEC, Belgium) have now published a commentary in Nature Communications.
Huge Potential
"2D materials have the potential to become the X-factor in future integrated electronics," says Professor Max Lemme, head of the Chair of Electronic Devices at RWTH Aachen University and spokesperson for the Aachen Graphene & 2D Materials Center. "I expect that they will initially enter the market in niche applications for specific sensors, as the requirements for manufacturing technologies could be lower. But I also believe that 2D materials will play an important role in photonic integrated circuits and in future neuromorphic computing applications. Here we are still in the early stages, but the initial results are already very promising."
In fact, more than a dozen 2D materials have already been discovered that exhibit programmable switching resistance - the fundamental property for building devices (memristors) - that can be used to mimic the behavior of synapses and neurons. While many fundamental aspects remain to be understood, the first memristors based on 2D materials have demonstrated competitive performance as well as a wide range of desirable other features, such as nonclonability and high-frequency switching for communication systems. In fact, such memristors are being studied in depth in the Cluster4Future project "NeuroSys", which started in January 2022.
Another future field in which 2D materials can play an important role is quantum technologies. "There is consistent evidence that 2D materials have great potential for quantum computing as well as quantum communication and novel quantum sensing," says Professor Christoph Stampfer, head of the "2D Materials and Quantum Devices Group" at RWTH Aachen University and co-author of the commentary. "Speaking of quantum computing, 2D materials are now eight to 12 years ahead of other platforms such as silicon - spin qubits based on 2D materials, for example, are within reach but have not yet been demonstrated. However, the flexibility offered by the 2D platform could offer great advantages in the medium to long term and allow us to overcome some of the obstacles encountered by other platforms, such as coupling spins with photons."
The commentary was published as open access in Nature Communications: