Rapid NEGF-based calculation of ballistic current in ultra-short DG MOSFETs for circuit simulation

• Autorzy: Hosenfeld F. , Horst F.. , Graef M. , Farokhnejad A. , Kloes A. , Iniguez B. , Lime F.
• Języki publikacji: EN

Abstrakty

EN

Shrinking gate length in conventional MOSFETs leads to increasing short channel effects like source-to-drain (SD) tunneling. Compact modeling designers are challenged to model these quantum mechanical effects. The complexity lies in the set-up between time efficiency, physical model relation and analytical equations. Multi-scale simulation bridges the gap between compact models, its fast and efficient calculation of the device terminal voltages, and numerical device models which consider the effects of nanoscale devices. These numerical models iterate between Poisson- and Schroedinger equation which significantly slows down the simulation performance. The physicsbased consideration of quantum effects like the SD tunneling makes the non-equilibrium Green’s function (NEGF) to a stateof-the-art method for the simulation of devices in the sub 10 nm region. This work introduces a semi-analytical NEGF model for ultra-short DG MOSFETs. Applying the closed-form potential solution of a classical compact model, the model turns the NEGF from an iterative numerical solution into a straightforward calculation. The applied mathematical approximations speed up the calculation time of the 1D NEGF. The model results for the ballistic channel current in DG-MOSFETs are compared with numerical NanoMOS TCAD [1] simulation data. Shown is the accurate potential calculation as well as the good agreement of the current characteristic for temperatures down to 75 K for channel lengths from 6 nm to 20 nm and channel thickness from 1.5 nm to 3 nm.

Słowa kluczowe

EN

ultra-short Double-Gate MOSFET; nonequilibrium Green's function; NEGF; ballistic transport; source-to-drain tunneling; ultra-thin body; UTB; compact model; multi-scale simulation

PL

ultra-short Double-Gate MOSFET; nierównowagowe funkcje Greena; NEGF; transport balistyczny; tunelowanie źródło-dren; model kompaktowy; symulacja wieloskalowa

• Wydawca: Lodz University of Technology. Department of Microelectronics and Computer Science
• Czasopismo: International Journal of Microelectronics and Computer Science
• Rocznik: 2016
• Tom: Vol. 7, nr 2
• Strony: 65--72
• Opis fizyczny: Bibliogr. 20 poz., il. kolor., wykr.

Twórcy

autor

Hosenfeld F.

• University Rovira i Virgili, Tarragona
• Research Group Nanoelectronics / Device Modeling at the Competence Center for Nanotechnology and Photonics, Technische Hochschule Mittelhessen, Giessen, German

autor

Horst F..

• University Rovira i Virgili, Tarragona
• Research Group Nanoelectronics / Device Modeling at the Competence Center for Nanotechnology and Photonics, Technische Hochschule Mittelhessen, Giessen, German

autor

Graef M.

• University Rovira i Virgili, Tarragona
• Research Group Nanoelectronics / Device Modeling at the Competence Center for Nanotechnology and Photonics, Technische Hochschule Mittelhessen, Giessen, German

autor

Farokhnejad A.

• University Rovira i Virgili, Tarragona
• Technische Hochschule Mittelhessen, Giessen, Germany

autor

Kloes A.

• Technische Hochschule Mittelhessen, Giessen, Germany

autor

Iniguez B.

• University Rovira i Virgili, Tarragona

autor

Lime F.

• University Rovira i Virgili, Tarragona

Bibliografia

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