Showing posts with label short-channel effects. Show all posts
Showing posts with label short-channel effects. Show all posts

Oct 25, 2020

[paper] Compact Modeling of Organic TFT

Jakob Pruefer, Jakob Leise, Ghader Darbandy, Aristeidis Nikolaou, Hagen Klauk, James W. Borchert, Benjamín Iñíguez, Fellow, IEEE, Thomas Gneiting, Member, IEEE
and Alexander Kloes, Senior Member, IEEE
Compact Modeling of Short-Channel Effects in Staggered Organic Thin-Film Transistors
IEEE Transactions on Electron Devices, vol. 67, no. 11, pp. 5082-5090, Nov. 2020
DOI: 10.1109/TED.2020.3021368.

Abstract:This article introduces analytical compact models of short-channel effects in staggered organic thinfilm transistors (TFTs). The effects of subthreshold-swing degradation, threshold-voltage roll-off, and drain-induced barrier lowering (DIBL) on the static current–voltage characteristics of staggered TFTs are extracted from an analytical potential solution of the 2-D problem of the staggered geometry. This solution is derived by using the Schwarz–Christoffel transformation that leads to a complex mapping function linking the staggered geometry to an equivalent in another coordinate system for which an analytical potential solution exists. The commercial TCAD is used to verify the compact models. Finally, the closed-form and physics-based equations are incorporated into an existing compact current model and verified by measurements on staggered organic TFTs with channel lengths as small as 0.4 µm fabricated on flexible plastic substrates by stencil lithography.
Fig:(a) Schematic cross section and (b) simplified geometry 
of the staggered organic TFTs for the TCAD simulations.

Acknowledgement: This work was supported in part by the German Federal Ministry of Education and Research under Grant 13FH015IX6 Strukturnahe Modellierung organischer flexibler KurzkanalTFTs (Structure-Oriented Modeling of Organic FLEXible short-channel TFTs) (SOMOFLEX), in part by the EU H2020 Marie Sklodowska-Curie actions (MSCA) Research and Innovation Staff Exchange (RISE) Project Design Oriented ModellINg for flexible electrOnics (DOMINO) under Grant 645760, and in part by the German Research Foundation (DFG) under Grant KL 1042/9-2 (SPP FFlexCom). 

Jun 22, 2020

[paper] “Extrinsic” Compact Model of the MOSFET Drain Current

V. O. Turin, R. S. Shkarlat, G. I. Zebrev, B. Iñiguez and M. S. Shur
The “Extrinsic” Compact Model of the MOSFET Drain Current Based on a New Interpolation Expression for the Transition Between Linear and Saturation Regimes with a Monotonic Decrease of the Differential Conductance to a Nonzero Value
2020 4th IEEE EDTM, Penang, Malaysia
2020, pp. 1-4
doi: 10.1109/EDTM47692.2020.9117810

Abstract: Previously, we proposed a new interpolation expression to bridge the transition between the linear and the saturation regimes of “intrinsic” MOSFET. This approach, in contrast to the traditional one, gives a monotonic decrease of the differential conductance from the maximum value in the linear regime to the minimum value in the saturation regime. Later, we proposed a linear approximation for an “extrinsic” MOSFET drain current dependence on the “extrinsic” drain bias in the saturation regime for not very high drain bias when nonlinear effects can be neglected. To obtain this approximation, an equation for the output differential resistance of the “extrinsic” MOSFET in saturation regime was obtained, that is similar to the result known from the theory of the common source MOSFET amplifier with source degeneration. In this paper, we combine these two results and present an “extrinsic” compact model for a short-channel MOSFET above threshold drain current with proper account of the differential conductance in the saturation regime.