摘要
二维半导体具有原子级薄的体厚度和表面无悬挂键的特点,是实现下一代晶体管微缩的重要候选材料之一.超短沟道的二维水平结构晶体管已通过多种方法成功制备,但通常需要复杂的设备和高精度的制造工艺,并且难以微缩至亚10 nm或亚5 nm的沟道长度.垂直晶体管是一种电流自上而下输运的新型器件结构,其中器件的栅极长度或者沟道长度取决于半导体的厚度而非光刻精度.因此,二维半导体在垂直晶体管中展现出了独特的应用前景.本文综述了基于二维半导体构建垂直晶体管的进展,包括二维垂直晶体管的基本结构、工作机制与器件性能等.
With transistor channel length scaled to sub-10 nm,silicon(Si)-based semiconductor scaling technology has gradually shown more and more challenges.The most notable one is the poor electrostatic control of the gate electric field on the silicon channel with increased power consumption and short-channel effect.On the other hand,two-dimensional semiconductors feather dangling-bonds-free surface,and the carriers are confined in their atomically thin channels,exhibiting excellent electronic performances at atomic-thin body thickness,which is expected to further scale the size of transistors.Two-dimensional semiconductor transistors with short channels have been successfully fabricated by various methods,but usually require complex equipment and high-energy fabrication processes,and become increasingly difficult in the sub-10 nm or sub-5 nm region.Vertical field-effect transistors(VEFTs),in which the channel material is sandwiched between source-drain electrodes,are expected to achieve ultra-short channel-length devices.Vertical transistors have naturally shorter channel lengths,are defined only by the thickness of the semiconductor material,and thus can deliver large drive currents that were previously unachievable using conventional planar device structures.In order to achieve effective gate modulation and current switching performance,traditional organic vertical transistors use mesh-like conductive materials such as metal nanowires and carbon nanotubes as the bottom electrode,through which the gate electric field can penetrate.Although the porous electrode as the bottom electrode reduces the shielding effect of the gate electric field and improves the gate control of the device,its rough surface hinders the construction of ultrashort-channel vertical transistors.On the other hand,from a performance perspective,VFETs based on perforated electrodes cannot fully unlock the potential that vertical transistors may offer.In recent years,with the emergence of graphene,a new type of graphene-based vertical transistor has b
作者
乐志凯
刘潇
李运鑫
刘丽婷
刘渊
Zhikai Le;Xiao Liu;Yunxin Li;Liting Liu;Yuan Liu(School of Physics and Electronics,Hunan University,Changsha 410082,China)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2023年第22期2901-2910,共10页
Chinese Science Bulletin
基金
国家自然科学基金(U22A2074,51991341)资助。
关键词
二维半导体
垂直晶体管
器件结构
器件性能
two-dimensional semiconductor
vertical transistor
device structure
device performance
