Terahertz characterization of single-walled carbon nanotube and graphene on-substrate thin films

Min Liang, Ziran Wu, Liwei Chen, Li Song, P. Ajayan, Hao Xin

Research output: Contribution to journalArticle

37 Citations (Scopus)

Abstract

In this paper, single-walled carbon nanotube (SWNT) thin films with thicknesses on the order of hundreds nanometers on glass substrates and a graphene thin film (2-3 layers) on a glass substrate are characterized via terahertz time-domain spectroscopy. The substrate permittivity is first characterized. The thin film is then treated as a surface boundary condition between the substrate and air. Using the uniform field approximation, the surface conductivities of these films are extracted. To improve accuracy, precise thickness of the sample substrate is calculated through an iteration process in both dielectric constant extraction and surface conductivity extraction. Uncertainty analysis of the measured thin-film properties is performed. The SWNT results show consistent surface conductivities for samples on different substrates and with different film thicknesses. The measured graphene terahertz conductivity is comparable to the values reported in the literature at dc and optical frequency. This characterization method has been successfully applied as a means to evaluate metallic content of SWNT samples to verify a metallic SWNT removing process using high-power microwave irradiation.

Original languageEnglish (US)
Article number5944999
Pages (from-to)2719-2725
Number of pages7
JournalIEEE Transactions on Microwave Theory and Techniques
Volume59
Issue number10 PART 2
DOIs
StatePublished - 2011

Fingerprint

Single-walled carbon nanotubes (SWCN)
Graphene
graphene
carbon nanotubes
Thin films
Substrates
thin films
conductivity
Permittivity
permittivity
Glass
Microwave irradiation
Uncertainty analysis
glass
iteration
Film thickness
film thickness
Boundary conditions
Spectroscopy
boundary conditions

Keywords

  • Graphene
  • Single-walled carbon nanotube (SWNT)
  • Surface conductivity
  • Terahertz
  • Time-domain spectroscopy (TDS)

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Condensed Matter Physics
  • Radiation

Cite this

Terahertz characterization of single-walled carbon nanotube and graphene on-substrate thin films. / Liang, Min; Wu, Ziran; Chen, Liwei; Song, Li; Ajayan, P.; Xin, Hao.

In: IEEE Transactions on Microwave Theory and Techniques, Vol. 59, No. 10 PART 2, 5944999, 2011, p. 2719-2725.

Research output: Contribution to journalArticle

Liang, Min ; Wu, Ziran ; Chen, Liwei ; Song, Li ; Ajayan, P. ; Xin, Hao. / Terahertz characterization of single-walled carbon nanotube and graphene on-substrate thin films. In: IEEE Transactions on Microwave Theory and Techniques. 2011 ; Vol. 59, No. 10 PART 2. pp. 2719-2725.
@article{d439fc1ba8344cbc8d3b47092cbc304f,
title = "Terahertz characterization of single-walled carbon nanotube and graphene on-substrate thin films",
abstract = "In this paper, single-walled carbon nanotube (SWNT) thin films with thicknesses on the order of hundreds nanometers on glass substrates and a graphene thin film (2-3 layers) on a glass substrate are characterized via terahertz time-domain spectroscopy. The substrate permittivity is first characterized. The thin film is then treated as a surface boundary condition between the substrate and air. Using the uniform field approximation, the surface conductivities of these films are extracted. To improve accuracy, precise thickness of the sample substrate is calculated through an iteration process in both dielectric constant extraction and surface conductivity extraction. Uncertainty analysis of the measured thin-film properties is performed. The SWNT results show consistent surface conductivities for samples on different substrates and with different film thicknesses. The measured graphene terahertz conductivity is comparable to the values reported in the literature at dc and optical frequency. This characterization method has been successfully applied as a means to evaluate metallic content of SWNT samples to verify a metallic SWNT removing process using high-power microwave irradiation.",
keywords = "Graphene, Single-walled carbon nanotube (SWNT), Surface conductivity, Terahertz, Time-domain spectroscopy (TDS)",
author = "Min Liang and Ziran Wu and Liwei Chen and Li Song and P. Ajayan and Hao Xin",
year = "2011",
doi = "10.1109/TMTT.2011.2160197",
language = "English (US)",
volume = "59",
pages = "2719--2725",
journal = "IEEE Transactions on Microwave Theory and Techniques",
issn = "0018-9480",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "10 PART 2",

}

TY - JOUR

T1 - Terahertz characterization of single-walled carbon nanotube and graphene on-substrate thin films

AU - Liang, Min

AU - Wu, Ziran

AU - Chen, Liwei

AU - Song, Li

AU - Ajayan, P.

AU - Xin, Hao

PY - 2011

Y1 - 2011

N2 - In this paper, single-walled carbon nanotube (SWNT) thin films with thicknesses on the order of hundreds nanometers on glass substrates and a graphene thin film (2-3 layers) on a glass substrate are characterized via terahertz time-domain spectroscopy. The substrate permittivity is first characterized. The thin film is then treated as a surface boundary condition between the substrate and air. Using the uniform field approximation, the surface conductivities of these films are extracted. To improve accuracy, precise thickness of the sample substrate is calculated through an iteration process in both dielectric constant extraction and surface conductivity extraction. Uncertainty analysis of the measured thin-film properties is performed. The SWNT results show consistent surface conductivities for samples on different substrates and with different film thicknesses. The measured graphene terahertz conductivity is comparable to the values reported in the literature at dc and optical frequency. This characterization method has been successfully applied as a means to evaluate metallic content of SWNT samples to verify a metallic SWNT removing process using high-power microwave irradiation.

AB - In this paper, single-walled carbon nanotube (SWNT) thin films with thicknesses on the order of hundreds nanometers on glass substrates and a graphene thin film (2-3 layers) on a glass substrate are characterized via terahertz time-domain spectroscopy. The substrate permittivity is first characterized. The thin film is then treated as a surface boundary condition between the substrate and air. Using the uniform field approximation, the surface conductivities of these films are extracted. To improve accuracy, precise thickness of the sample substrate is calculated through an iteration process in both dielectric constant extraction and surface conductivity extraction. Uncertainty analysis of the measured thin-film properties is performed. The SWNT results show consistent surface conductivities for samples on different substrates and with different film thicknesses. The measured graphene terahertz conductivity is comparable to the values reported in the literature at dc and optical frequency. This characterization method has been successfully applied as a means to evaluate metallic content of SWNT samples to verify a metallic SWNT removing process using high-power microwave irradiation.

KW - Graphene

KW - Single-walled carbon nanotube (SWNT)

KW - Surface conductivity

KW - Terahertz

KW - Time-domain spectroscopy (TDS)

UR - http://www.scopus.com/inward/record.url?scp=84860364398&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84860364398&partnerID=8YFLogxK

U2 - 10.1109/TMTT.2011.2160197

DO - 10.1109/TMTT.2011.2160197

M3 - Article

VL - 59

SP - 2719

EP - 2725

JO - IEEE Transactions on Microwave Theory and Techniques

JF - IEEE Transactions on Microwave Theory and Techniques

SN - 0018-9480

IS - 10 PART 2

M1 - 5944999

ER -