TY - JOUR
T1 - Impact of strong quantum confinement on the performance of a highly asymmetric device structure
T2 - Monte Carlo particle-based simulation of a focused-ion-beam MOSFET
AU - Knezevic, Irena
AU - Vasileska, Dragica
AU - Ferry, David K.
N1 - Funding Information:
Manuscript received December 17, 2001; revised February 11, 2002. This work was supported in part by the Semiconductor Research Corporation, the Office of Naval Research, under Contract N000149910318 and the National Science Foundation under NSF-CAREER ECS-9875051. The review of this paper was arranged by Editor C.-Y. Lu.
PY - 2002/6
Y1 - 2002/6
N2 - A highly asymmetric 250 nm n-channel MOSFET, with a 70-nm p + -implant placed at the source end of the channel (achievable by focused-ion-beam (FIB) implantation, so the device is named FIBMOS), has been simulated using a two-dimensional (2-D) coupled Monte Carlo-Poisson solver, in which quantum confinement effects have been taken into account by incorporating an effective potential scheme into the particle simulator. Although the device is a long-channel one, its performance is dictated by the highly doped p+-implant at the source end of the channel, and it is crucial to properly account for the quantum-confinement effects in transport, especially at the implant/oxide interface. We show that parameters such as threshold voltage and device transconductance are extremely sensitive to the proper treatment of quantization effects. On the other hand, the built-in electric field, due to the pronounced asymmetry caused by the presence of the p +-implant, drastically influences the carrier transport, and consequently, the device output characteristics, in particular the magnitude of the velocity overshoot effect and the low-field electron mobility.
AB - A highly asymmetric 250 nm n-channel MOSFET, with a 70-nm p + -implant placed at the source end of the channel (achievable by focused-ion-beam (FIB) implantation, so the device is named FIBMOS), has been simulated using a two-dimensional (2-D) coupled Monte Carlo-Poisson solver, in which quantum confinement effects have been taken into account by incorporating an effective potential scheme into the particle simulator. Although the device is a long-channel one, its performance is dictated by the highly doped p+-implant at the source end of the channel, and it is crucial to properly account for the quantum-confinement effects in transport, especially at the implant/oxide interface. We show that parameters such as threshold voltage and device transconductance are extremely sensitive to the proper treatment of quantization effects. On the other hand, the built-in electric field, due to the pronounced asymmetry caused by the presence of the p +-implant, drastically influences the carrier transport, and consequently, the device output characteristics, in particular the magnitude of the velocity overshoot effect and the low-field electron mobility.
KW - Asymmetric device structures
KW - FIBMOS device
KW - Monte Carlo simulation
KW - Quantization
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U2 - 10.1109/TED.2002.1003723
DO - 10.1109/TED.2002.1003723
M3 - Article
AN - SCOPUS:0036610454
SN - 0018-9383
VL - 49
SP - 1019
EP - 1026
JO - IEEE Transactions on Electron Devices
JF - IEEE Transactions on Electron Devices
IS - 6
ER -