A hot-emitter transistor based on stimulated emission of heated carriers.
Dongming SunXin-Zhe WangCong ShenLai-Peng MaXu-Qi YangYue KongWei MaYan LiangShun FengXiao-Yue WangYu-Ning WeiXi ZhuBo LiChang-Ze LiShi-Chao DongLi-Ning ZhangWen-Cai RenDong-Ming SunHui-Ming ChengPublished in: Nature (2024)
Hot-carrier transistors are a class of devices that leverage the excess kinetic energy of carriers. Unlike regular transistors, which rely on steady-state carrier transport, hot-carrier transistors modulate carriers to high-energy states, resulting in enhanced device speed and functionality. These characteristics are essential for applications that demand rapid switching and high-frequency operations, such as advanced telecommunications and cutting-edge computing technologies 1-5 . However, the traditional mechanisms of hot-carrier generation are either carrier injection 6-11 or acceleration 12,13 , which limit device performance in terms of power consumption and negative differential resistance 14-17 . Mixed-dimensional devices, which combine bulk and low-dimensional materials, can offer different mechanisms for hot-carrier generation by leveraging the diverse potential barriers formed by energy-band combinations 18-21 . Here we report a hot-emitter transistor based on double mixed-dimensional graphene/germanium Schottky junctions that uses stimulated emission of heated carriers to achieve a subthreshold swing lower than 1 millivolt per decade beyond the Boltzmann limit and a negative differential resistance with a peak-to-valley current ratio greater than 100 at room temperature. Multi-valued logic with a high inverter gain and reconfigurable logic states are further demonstrated. This work reports a multifunctional hot-emitter transistor with significant potential for low-power and negative-differential-resistance applications, marking a promising advancement for the post-Moore era.