The dependence of the high-frequency performance of graphene field-effect transistors on channel transport properties
Artikel i vetenskaplig tidskrift, 2020

This paper addresses the high-frequency performance limitations of graphene field-effect transistors (GFETs) caused by material imperfections. To understand these limitations, we performed a comprehensive study of the relationship between the quality of graphene and surrounding materials and the high-frequency performance of GFETs fabricated on a silicon chip. We measured the transit frequency (fT) and the maximum frequency of oscillation (fmax) for a set of GFETs across the chip, and as a measure of the material quality, we chose low-field carrier mobility. The low-field mobility varied across the chip from 600 cm2/Vs to 2000 cm2/Vs, while the fT and fmax frequencies varied from 20 GHz to 37 GHz. The relationship between these frequencies and the low-field mobility was observed experimentally and explained using a methodology based on a small-signal equivalent circuit model with parameters extracted from the drain resistance model and the charge-carrier velocity saturation model. Sensitivity analysis clarified the effects of equivalent-circuit parameters on the fT and fmax frequencies. To improve the GFET high-frequency performance, the transconductance was the most critical parameter, which could be improved by increasing the charge-carrier saturation velocity by selecting adjacent dielectric materials with optical phonon energies higher than that of SiO2.

transconductance.

microwave electronics

high frequency

maximum frequency of oscillation

transit frequency

graphene

field-effect transistors

contact resistances

Författare

Muhammad Asad

Chalmers, Mikroteknologi och nanovetenskap (MC2), Terahertz- och millimetervågsteknik

Marlene Bonmann

Chalmers, Mikroteknologi och nanovetenskap (MC2), Terahertz- och millimetervågsteknik

Xinxin Yang

Chalmers, Mikroteknologi och nanovetenskap (MC2), Terahertz- och millimetervågsteknik

Andrei Vorobiev

Chalmers, Mikroteknologi och nanovetenskap (MC2), Terahertz- och millimetervågsteknik

Kjell Jeppson

Chalmers, Mikroteknologi och nanovetenskap (MC2), Terahertz- och millimetervågsteknik

Jan Stake

Chalmers, Mikroteknologi och nanovetenskap (MC2), Terahertz- och millimetervågsteknik

et. al.

IEEE Journal of the Electron Devices Society

2168-6734 (ISSN)

Vol. 8 457-464

Infrastruktur

Kollberglaboratoriet

Ämneskategorier

Teknisk mekanik

Elektroteknik och elektronik

DOI

10.1109/JEDS.2020.2988630

Mer information

Senast uppdaterat

2020-07-15