A Comprehensive Graphene FET Model for Circuit Design

Abstract

During the last years, Graphene based Field Effect Transistors (GFET) have shown outstanding RF performance; therefore, they have attracted considerable attention from the electronic devices and circuits communities. At the same time, analytical models that predict the electrical characteristics of GFETs have evolved rapidly. These models, however, have a complexity level that can only be handled with the help of a circuit simulator. On the other hand, analog circuit designers require simple models that enable them to carry out fast hand calculations, i.e., to create circuits using small-signal hybrid-{\pi} models, calculate figures of merit, estimate gains, pole-zero positions, etc. This paper presents a comprehensive GFET model that is simple enough for being used in hand-calculations during circuit design and at the same time it is accurate enough to capture the electrical characteristics of the devices in the operating regions of interest. Closed analytical expressions are provided for the drain current ID, small-signal transconductance gain gm, output resistance ro, and parasitic Vgs and Cgd. In addition, figures of merit such as intrinsic voltage gain AV, transconductance efficiency gm/ID, and transit frequency fT are presented. The proposed model has been compared to a complete analytical model and also to measured data available in current literature. The results show that the proposed model follows closely to both the complete analytical model and the measured data; therefore, it can be successfully applied in the design of GFET analog circuits.Comment: 9 pages,11 figure

Prior knowledge input neural network method for GFET description

“…(1). As a fundamental formula, its numerator comes from the well-known Shichman-Hodges model [25], while the denominator comes from [26], which simply represents the special bipolar character of GFETs.…”

Overview of carbon-based circuits and systems

“…1(b). The potential use of this device in ICs has prompted the interest of a number of researchers for finding out electrical models which can be used for circuit design and simulation [12], [14], [18], [19]. Among others, the model proposed by Frégonèse et al at the University of Bordeaux [12] provides an accurate description of the device operation, including its main non-ideal and second-order phenomena, and can be coded in SPICE or Verilog-A for circuit simulation.…”

“…Among others, the model proposed by Frégonèse et al at the University of Bordeaux [12] provides an accurate description of the device operation, including its main non-ideal and second-order phenomena, and can be coded in SPICE or Verilog-A for circuit simulation. Based on this model, the drain-source current of a G-FET can be expressed as [14]:…”

“…These methods are running in parallel with the development of SPICE models to accurately simulate CNT-FET/G-FET circuits and to systematize their analysis and design by following a top-down/bottom-up approach [6]- [14].…”

Modelling of a sensor for gas adsorption on P and Ga doped GNRFET

“…The expression for the Transconductance g m obtained by [12] g m = GS | V DS , const (2) where I d is drain current, V GS is gate to source voltage and V DS is drain to source voltage. The transconductance g m drops at large V GSi biasing voltages, mainly due to saturation voltage V SAT .…”