Files in this item

FilesDescriptionFormat

application/pdf

application/pdfDorgan_Vincent.pdf (1MB)
(no description provided)PDF

Description

Title:Mobility and Saturation Velocity in Graphene on Silicon Dioxide
Author(s):Dorgan, Vincent E.
Advisor(s):Pop, Eric
Department / Program:Electrical & Computer Eng
Discipline:Electrical & Computer Engr
Degree Granting Institution:University of Illinois at Urbana-Champaign
Degree:M.S.
Genre:Thesis
Subject(s):graphene
mobility
high-field
Abstract:Transport properties of exfoliated graphene samples on SiO2 are examined from four-probe electrical measurements combined with electrical and thermal modeling. Data are analyzed with practical models including gated carriers, thermal generation, “puddle” charge, and Joule heating. Graphene mobility is characterized as a function of carrier density at temperatures from 300 to 500 K. In addition, electron drift velocity is obtained at high electric fields up to 2 V/μm, at both 80 K and 300 K. Mobility displays a peak vs. carrier density and decreases with rising temperature above 300 K. The drift velocity approaches saturation at fields >1 V/μm, shows an inverse dependence on carrier density (~n^-1/2), and decreases slightly with temperature. Saturation velocity is >3×10^7 cm/s at low carrier density, and remains greater than in Si up to 1.2×10^13 cm^-2 density. Transport appears primarily limited by the SiO2 substrate, but results suggest intrinsic graphene saturation velocity could be more than twice that observed here.
Issue Date:2010-08-20
URI:http://hdl.handle.net/2142/16801
Rights Information:Copyright 2010 Vincent E. Dorgan
Date Available in IDEALS:2010-08-20
Date Deposited:2010-08


This item appears in the following Collection(s)

Item Statistics