A Surface-Field-Based Model for Nanowire MOSFETs With Spatial Variations of Doping Profiles

Abstract

We report a novel method to solve the nonlinear 1-D Poisson's equation for the gate-all-around (GAA) nanowire MOSFETs with nonuniform doping profiles. An algebraic relation between the electric field and potential is identified to develop a surface-field-based compact model. Drain current is derived from the oxide-interface boundary condition to avoid the complicated surface-potential approach. As verified by the TCAD simulations, this analytic model is capable of continuously covering all operating regions of GAA nanowire MOSFETs with slowly varying doping profiles.Index Terms-Gate-all-around (GAA) nanowire MOSFET, Poisson's equation, spatial variations, surface-field-based model.

Explicit continuous charge-based compact model of surrounding gate MOSFET (SRGMOSFET) with smooth transition between partially-depleted to fully-depleted operation

“…Surrounding-gate MOSFETs (SRGMOSFETs) has been widely studied as the structure of logic devices to replace the conventional planar MOSFETs in improving the control over the short-channel effects [1][2][3][4]. For more than a decade, SRGMOSFET compact modeling has been an active research area and various types of compact models were reported [5][6][7][8][9][10][11][12][13][14][15][16][17][18]. In its early development, the compact models were obtained for the undoped case by solving the one-dimensional (1D) Poisson's equation that contains only the mobile-charge term [5][6][7][8][9][10][11][12][13][14][15][16][17][18].…”

“…For more than a decade, SRGMOSFET compact modeling has been an active research area and various types of compact models were reported [5][6][7][8][9][10][11][12][13][14][15][16][17][18]. In its early development, the compact models were obtained for the undoped case by solving the one-dimensional (1D) Poisson's equation that contains only the mobile-charge term [5][6][7][8][9][10][11][12][13][14][15][16][17][18]. However, due to the unintentional doping, the highly-doped body of SRGMOSFET has resulted in an increase of its threshold voltage.…”

“…However, due to the unintentional doping, the highly-doped body of SRGMOSFET has resulted in an increase of its threshold voltage. In order to incorporate this effect, various approximations were proposed to describe the nonlinear interaction between the mobile and the depletion charges [10,13,15,19,20]. Some models have adopted the physical intuition approximation.…”

Cylindrical gate all around Schottky barrier MOSFET with insulated shallow extensions at source/drain for removal of ambipolarity: a novel approach

“…Device performance with miniaturization is the vital goal of the microelectronics community. Cylindrical gate all around (CGAA) MOSFET with the reduced gate length of 22 nm is an ultimate solution [1][2][3] . CGAA provides excellent electrostatic gate control over the channel and drastically reduces short channel effects (SCEs) and hot carriers effects (HCEs) [4] .…”

Ambipolarity reduction in DMG asymmetric vacuum dielectric Schottky Barrier GAA MOSFET to improve hot carrier reliability

“…In recent years, MOSFET dimensions has drastically reduced approaching to nanoscale regime with steeply increased short channels effects [1][2][3][4]. At nanoscale the junction depletion width (p-n) at SourceChannel (S-C) and Channel-Drain (C-D) junctions can not be neglected as it degrades the ON current due to increased S-C and C-D resistance [5][6][7][8] and is actively involved in MOSFET device performance.…”