Big data revolutions have disrupted the power of advanced electronics, prompting engineers to rethink almost every aspect of the microchip. With large data sets to store, search and analyze at an increasing (A ferroelectric transistor that stores and computes in large quantities) level of complexity, these devices will be smaller, faster and more energy efficient to keep up with data production.
Ferroelectric field-effect transistors (FE-FETs) are among the most interesting solutions to this challenge. Like silicon-based transistors, FE-FETs are light switches that turn on and off at incredible speeds to communicate the 1s and 0s that computers use to do their work.
But FE-FETs have another function that conventional transistors don’t have: their ferroelectric properties allow them to retain electrical charge.
This property allows them to serve as non-volatile memory devices as well as computing devices. Being able to store and process data, FE-FETs are the subject of much research and development. A successful FE-FET design will reduce the threshold and threshold power consumption of traditional devices, whileA increasing speed.
Researchers from the School of Engineering and Applied Science at the University of Pennsylvania have developed a new FE-FET that shows record-breaking performance in math and memory.
Research recently published in Nature Nanotechnology by Deep Jariwala, Associate Professor in the Department of Electrical and Systems Engineering (ESE), and Kwan-Ho Kim, Ph.D. student in his laboratory, began to design.
They collaborated with Penn Engineering faculty members Troy Olsson, also an assistant professor at ESE, and Eric Stach, the Robert D. Bent Professor of Engineering in the Department of Science and Engineering (MSE) and Director of the Laboratory for Research on Structure. Of Matter (LRSM).
The transistor consists of a two-dimensional semiconductor called molybdenum disulfide (MoS2) and a ferroelectric material called aluminum scandium nitride (AlScN), showing for the first time that these two materials can be successfully combined to form transistors and ladders good for industrial production.
“Because we developed these devices that combine ferroelectric coatings and 2D semiconductors, they both work very well,” Jariwala says. “You can use them for collection and storage – individually and efficiently.”
The Penn Engineering team’s devices are notable for their unprecedented thinness, allowing each device to function in a small surface area. In addition, small devices can be produced in large quantities for industrial platforms.
“With our semiconductor, MoS2, at only 0.7 nanometers, we’re not sure it can survive the charge that our electrode material, AlScN, will put into it,” Kim said. “To our surprise, not only are they both alive, but the current rate allows the semiconductor to carry records as well.”
The bigger the device can be now, the faster it can work for the device. At the bottom of the resistance, fast memory space speed.
This combination of MoS2 and AlScN is a real breakthrough in transistor technology. FE-FETs from other research groups have continued to cling to the loss of ferroelectric properties as the devices shrink to approach scales suitable for industry.
Until this study, the reduction of the FE-FET led to a significant reduction of the “memory window”. This means that as engineers reduce the size of the transistor, the device develops an unreliable memory, mixing 1s and 0s and vice versa, compromising its overall performance.
Jarawala’s laboratory and its collaborators have achieved a design that enables large memory windows in small devices. With AlScN at 20 nanometers and MoS2 at 0.7 nanometers, the FE-FET stores data for quick access.
Olsson says, “The key is our light source, AlScN. Unlike most ferroelectric materials, it retains its unique properties even when thin. In a recent paper by my team, we showed that it can maintain its unique ferroelectric property even at a small thickness: 5 nanometers.
The Penn Engineering team’s next steps are focusing on this little bit to create devices that operate at low voltages to match the manufacturing of high-end consumer devices.
“Our FE-FET is very promising,” says Jariwala. “With further development, these flexible devices can have any place and any technology you can think of, especially those that are assisted by AI and consume, produce and it is processing big data – through insights and communications and more.”
Source: University of Pennsylvania School of Engineering and Applied Science
