In the relentless pursuit of energy-efficient semiconductor devices, a team of researchers led by C.R. Allemang from Sandia National Laboratories in Albuquerque, NM, has turned to an innovative technology that could reshape the future of computing and energy consumption. Their focus? Tunnel field-effect transistors (TFETs), a promising alternative to conventional transistors that could significantly enhance energy efficiency.
The end of Dennard scaling, which once allowed computing power to increase without additional energy costs, has left the industry scrambling for solutions. TFETs, which operate through quantum tunneling rather than thermionic emission, offer a potential path to sub-60 mV/dec subthreshold swing (SS), enabling low-voltage operation and reduced power consumption. However, traditional lateral TFETs have struggled with adequate on-state current and a broad SS operation window, limiting their practical applications.
Allemang and his team advocate for a new approach: areal TFETs. These devices use face-to-face tunnel junctions, offering step-function current turn-on characteristics and allowing the on-state current to scale with device area rather than width. “Areal TFETs represent a paradigm shift in tunnel transistor design,” Allemang explains. “By leveraging atomically thin layers and efficient band-to-band tunneling, we can overcome the limitations of traditional TFETs and unlock new levels of energy efficiency.”
The team’s research, published in the journal “Materials for Quantum Technology” (translated to English as “Materials for Quantum Technology”), highlights recent advancements in integrating 2D materials into tunneling structures. These materials facilitate efficient tunneling while addressing challenges of gate field screening. The review also discusses the prospects of epitaxial areal TFETs comprising III–V compound semiconductors and group-IV semiconductors, based on recent experimental progress.
The implications for the energy sector are substantial. As computing demands continue to grow, so does the need for energy-efficient technologies. TFETs could play a crucial role in reducing the power consumption of data centers, which are responsible for a significant portion of global energy use. “The potential impact of TFETs on the energy sector cannot be overstated,” says Allemang. “By enabling low-voltage operation and reduced power consumption, these devices could help us meet the growing demand for computing power while minimizing energy use.”
The research also delves into ongoing challenges in material synthesis, interface engineering, device fabrication, and integration pathways. Despite these hurdles, the team remains optimistic about the future of TFETs. “While there are still challenges to overcome, the progress we’ve seen in recent years is encouraging,” Allemang notes. “With continued research and development, TFETs could become a key technology in the quest for energy-efficient computing.”
As the industry continues to search for solutions to the end of Dennard scaling, the work of Allemang and his team offers a promising path forward. By exploring new materials and device configurations, they are paving the way for a future where energy-efficient computing is not just a possibility, but a reality.