High performance low-power transistor

Advancements in Transistor Technology

Challenges and Innovations

Advancements in transistor technology are essential as shrinking sizes present challenges to integrated circuits. Innovating with new operating principles is key to improving circuit performance.

Hot Carrier Transistors

Transistors leveraging excess carrier kinetic energy, known as hot carrier transistors, could enhance speed and functionality, though traditional generation methods have constrained their performance.

Breakthrough in Hot Carrier Generation

Introduction of SEHC

A research team, spearheaded by Prof. Liu Chi, Prof. Sun Dongming, and Prof. Cheng Huiming at the chinese Academy of Sciences' institute of Metal Research (IMR), has introduced a groundbreaking hot carrier generation mechanism known as stimulated emission of heated carriers (SEHC).

Development of HOET

The researchers have developed a novel hot-emitter transistor (HOET) that achieves an exceptionally low sub-threshold swing below 1 mV/dec and a peak-to-valley current ratio surpassing 100. This advancement presents a prototype for low-power, multifunctionl devices suited for the post-Moore's Law era.

Publication

The study was released in Nature.

Role of Low-Dimensional Materials

Graphene and Other Materials

Owing to their atomic-scale thickness and superior electrical and optical properties, low-dimensional materials such as graphene can effortlessly combine with other materials to form heterostructures. These configurations enable a diverse range of energy band combinations, paving the way for innovative hot carrier transistors.

Development of Innovative HOET

Researchers from IMR developed an innovative hot-emitter transistor by pairing graphene with germanium, introducing a new hot carrier generation process. The transistor is built with two graphene/germanium Schottky junctions in tandem.

Performance and Potential

As the device runs, germanium infuses high-energy carriers into the graphene base, which then diffuse to the emitter, inducing a notable current increase due to the preheated carriers. The system achieves a sub-threshold swing under 1 mV/dec, surpassing the conventional Boltzmann limit of 60 mV/dec.

The transistor also exhibits a peak-to-valley current ratio surpassing 100 at ambient temperatures, highlighting its capability for multi-valued logic computations.

Conclusion

According to Liu, this work expands the frontier of transistor research by adding a novel hot carrier transistor, which shows substantial promise for application in future high-performance and low-power multifunctional devices.

Source