Ultrashort Channel Length Black Phosphorus Field-Effect Transistors.
This paper reports high-performance top-gated black phosphorus (BP) field-effect transistors with channel lengths down to 20 nm fabricated using a facile angle evaporation process. By controlling the evaporation angle, the channel length of the transistors can be reproducibly controlled to be anywhere between 20 and 70 nm. The as-fabricated 20 nm top-gated BP transistors exhibit respectable on-state current (174 μA/μm) and transconductance (70 μS/μm) at a VDS of 0.1 V. Due to the use of two-dimensional BP as the channel material, the transistors exhibit relatively small short channel effects, preserving a decent on-off current ratio of 10(2) even at an extremely small channel length of 20 nm. Additionally, unlike the unencapsulated BP devices, which are known to be chemically unstable in ambient conditions, the top-gated BP transistors passivated by the Al2O3 gate dielectric layer remain stable without noticeable degradation in device performance after being stored in ambient conditions for more than 1 week. This work demonstrates the great promise of atomically thin BP for applications in ultimately scaled transistors.
Electrical and Computer Engineering, Michigan State University , East Lansing, Michigan 48824, United States.
Jinshui
J
Miao
Electrical and Computer Engineering, Michigan State University , East Lansing, Michigan 48824, United States.
Suoming
S
Zhang
Electrical and Computer Engineering, Michigan State University , East Lansing, Michigan 48824, United States.
Le
L
Cai
Electrical and Computer Engineering, Michigan State University , East Lansing, Michigan 48824, United States.
Martin
M
Scherr
Electrical and Computer Engineering, Michigan State University , East Lansing, Michigan 48824, United States.
Chuan
C
Wang
2D semiconductors; black phosphorus; device scaling; field-effect transistors; ultrashort channel length