[paper] Compact Modeling of Parasitic FET capacitance

Sharma, S. M., Singh, A., Dasgupta, S., & Kartikeyan, M. V. 

A review on the compact modeling of parasitic capacitance: 

from basic to advanced FETs. 

Journal of Computational Electronics

DOI: 10.1007/s10825-020-01515-4

Abstract: This paper presents a review on the development of parasitic-capacitance modeling for metal–oxide–semiconductor feldefect transistors (MOSFETs), covering models developed for the simple parallel-plate capacitance and the nonplanar and coplanar plate capacitances required for the intrinsic and extrinsic part of such devices. A comparative study of various extrinsic capacitance models with respect to a reference model is used to analyze the benefts of the various approaches. Capacitance models for basic MOSFETs and advance multigate FETs with two-dimensional (2D) and three-dimensional (3D) structures are reviewed. It is found that the elliptical feld lines between the gate electrodes and source/drain region are modeled very well, while deviations of ±2% in the orthogonal plate capacitance are observed when the gate electrode thickness is varied from 5 to 20nm.

Fig: The 3D structure of a FinFET

Acknowledgements: The authors would like to thank the Department of Electronics and Communication Engineering, IIT Roorkee, for their valuable support in carrying out this research work.

[paper] RESURF Model and Electrical Characteristics of Finger-Type STI Drain Extended MOS Transistors

RESURF Model and Electrical Characteristics of Finger-Type STI Drain Extended MOS Transistors
H. C. Tsai, R. H. Liou and C. Lien
IEEE Transactions on Electron Devices
vol. 63, no. 12, pp. 4603-4609, Dec. 2016

Abstract: Finger-type shallow trench isolation (finger STI) drain extended MOS transistors are fabricated and its electrical characteristics is studied. Polyplate on a finger STI served as a reduced surface field is adopted to enhance breakdown voltage (BV) by reducing the effective doping concentration of the drain extension (DE) finger. The conformal mapping method, which relates the reduction of the doping concentration to the width (z_o) of the DE finger, the gap (z_d) between the polyplate and the DE finger, and the STI depth (y_s), is used to estimate the reduction of the doping concentration theoretically. Based on this reduced doping concentration, a BV model is derived. The predictions of this model agree very well with the experimental data.

Keywords: Conformal mapping, Doping, Electric breakdown, MOS devices, Semiconductor process modeling, Silicon, Transistors, Drain extended MOS (DEMOS), Lateral double Diffused MOS (LDMOS), poly field plate, reduced surface field (RESURF)

doi: 10.1109/TED.2016.2605504
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