Unleashing Power: How Hot Carrier Transistors Are Revolutionizing Efficiency Beyond Moore’s Law!

hot carrier transistors efficiency Moore’s Law

New Hot Carrier Transistors Break Efficiency Barriers Beyond Moore’s Law

Introduction of Graphene-Germanium Hot-Emitter Transistor

Researchers have pioneered an advanced graphene-germanium hot-emitter transistor, leveraging a groundbreaking hot carrier generation method that delivers unparalleled performance. This innovation sets the stage for the development of low-power, high-efficiency multifunctional devices.

As transistors, the essential elements of integrated circuits, become ever smaller, they face increasing challenges. To elevate circuit performance, it has become crucial to devise transistors based on novel operating principles.

Hot carrier transistors, which exploit the kinetic energy of charge carriers, present a promising avenue for boosting both speed and functionality. Yet, traditional approaches to generating hot carriers have limited their potential.

A research team headed by Professors Chi Liu, Dongming Sun, and Huiming Cheng from the Institute of Metal Research (IMR) at the Chinese Academy of Sciences has introduced a new hot carrier generation concept, termed “stimulated emission of heated carriers (SEHC).” Their innovation, the hot-emitter transistor (HOET), achieves an extraordinarily low sub-threshold swing of less than 1 mV/dec and a peak-to-valley current ratio greater than 100. This breakthrough offers a prototype for post-Moore era low-power multifunctional devices.

This groundbreaking research has been featured in Nature.

hot carrier transistors efficiency Moore’s Law: The Role of Low-Dimensional Materials

Low-dimensional materials like graphene, with their atomic-level thickness, exceptional electrical and optical properties, and defect-free surfaces, lend themselves to forming hetero-structures with other materials. These hetero-structures enable a wide range of energy band configurations, providing fertile ground for the creation of novel hot carrier transistors.

At IMR, researchers developed a hot-emitter transistor by integrating graphene with germanium, which led to a novel hot carrier generation mechanism. This transistor features two interconnected graphene/germanium Schottky junctions. When in operation, germanium injects high-energy carriers into the graphene layer, where they diffuse towards the emitter.

The result is a marked rise in current, thanks to the preheated carriers present in the emitter. This design achieves a sub-threshold swing of less than 1 mV/dec, far surpassing the conventional Boltzmann limit of 60 mV/dec. Additionally, the transistor exhibits a peak-to-valley current ratio exceeding 100 at ambient temperatures, showcasing the potential for multi-valued logic computing.

“This work represents a significant breakthrough in transistor research, introducing a new member to the hot carrier transistor family and promising broad applications for future high-performance, low-power multifunctional devices,” commented Liu.

Reference

“A hot-emitter transistor based on stimulated emission of heated carriers” by Chi Liu, Xin-Zhe Wang, Cong Shen, Lai-Peng Ma, Xu-Qi Yang, Yue Kong, Wei Ma, Yan Liang, Shun Feng, Xiao-Yue Wang, Yu-Ning Wei, Xi Zhu, Bo Li, Chang-Ze Li, Shi-Chao Dong, Li-Ning Zhang, Wen-Cai Ren, Dong-Ming Sun, and Hui-Ming Cheng, published on August 14, 2024, in Nature.
DOI: 10.1038/s41586-024-07785-3

This study was conducted in collaboration with Ren Wencai’s team from IMR and Zhang Lining’s team from Peking University.