Direct determination of threshold condition in DG-MOSFETs from the gm/ID curve

Abstract In this work we apply the current-based threshold voltage definition (equality between the drift and diffusion components of drain current) to intrinsic symmetric double-gate MOSFETs. We show that the half maximum point of the gm/ID (transconductance-to-current ratio) curve in the linear region corresponds exactly to the condition IDdrift = IDdiff when mobility variation is neglected. Numerical simulations show that the threshold voltages determined from the gm/ID curve and from the IDdrift = IDdiff condition differ by about ϕt/2 (one half of the thermal voltage) when considering realistic mobility variations. Simulation results show that the threshold voltages determined with the gm/ID procedure are close to those obtained with the Y (= I D / g m ) function method for a considerable range of silicon film thicknesses, channel lengths, and temperature values. The current-based procedure has also been successfully applied experimentally to a FinFET over a wide temperature range.

[1]  Paul Losleben,et al.  Advanced Research in VLSI , 1987 .

[2]  O. Faynot,et al.  Multiple gate devices: advantages and challenges , 2005 .

[3]  O. Faynot,et al.  A simple parameter extraction method for ultra-thin oxide MOSFETs , 1995 .

[4]  C. Sah,et al.  Effects of diffusion current on characteristics of metal-oxide (insulator)-semiconductor transistors☆ , 1966 .

[5]  Y. Taur,et al.  A continuous, analytic drain-current model for DG MOSFETs , 2004 .

[6]  J. Wang,et al.  Threshold Voltage of Ultrathin Gate-Insulator MOSFETs , 2009 .

[7]  Juan Muci,et al.  Understanding threshold voltage in undoped-body MOSFETs: An appraisal of various criteria , 2006, Microelectron. Reliab..

[8]  Carlos Galup-Montoro,et al.  An MOS transistor model for analog circuit design , 1998, IEEE J. Solid State Circuits.

[9]  Yu-Jung Huang,et al.  Reliability and routability consideration for MCM placement , 2002, Microelectron. Reliab..

[10]  Carlos Galup-Montoro,et al.  Derivation of the unified charge control model and parameter extraction procedure , 1999 .

[11]  Gerard Ghibaudo,et al.  New method for the extraction of MOSFET parameters , 1988 .

[12]  Carver A. Mead,et al.  A Physical Charge-Controlled Model for MOS Transistors , 1987 .

[13]  Juin J. Liou,et al.  A review of recent MOSFET threshold voltage extraction methods , 2002, Microelectron. Reliab..

[14]  Carlos Galup-Montoro,et al.  Unambiguous extraction of threshold voltage based on the ACM model , 2004 .

[15]  Yuan Taur,et al.  Analytic solutions of charge and capacitance in symmetric and asymmetric double-gate MOSFETs , 2001 .

[16]  Christian Enz,et al.  A Design Oriented Charge-based Current Model for Symmetric DG MOSFET and its Correlation with the EKV Formalism , 2005 .

[17]  Marcelo Antonio Pavanello,et al.  Cryogenic operation of FinFETs aiming at analog applications , 2009 .

[18]  F. Balestra,et al.  Double-gate silicon-on-insulator transistor with volume inversion: A new device with greatly enhanced performance , 1987, IEEE Electron Device Letters.

[19]  Antonios Bazigos,et al.  Determining MOSFET Parameters in Moderate Inversion , 2007, 2007 IEEE Design and Diagnostics of Electronic Circuits and Systems.