Ultraviolet/ozone treatment to reduce metal-graphene contact resistance

Li, Wei; Liang, Yiran; Yu, Dongli; Peng, Lian‐Mao; Pernstich, Kurt P.; Shen, Tian; Walker, Angela R. Hight; Cheng, Guangjun; Hacker, Christina A.; Richter, Curt A.; Li, Qiliang; Gundlach, David J.; Liang, Xuelei

doi:10.1063/1.4804643

Cited by 121 publications

(110 citation statements)

References 29 publications

(23 reference statements)

Supporting

Mentioning

105

Contrasting

Order By: Relevance

“…Recently, contact resistances of 500 Ohm· µm were reported for graphene/nickel contacts [28], while special treatment procedures can reduce this value down to 100-200 Ohm· µm [29,30]. These values correspond to the recharging frequency of the order of 10 13 s −1 for L = 1 µm and d = 50 nm, which allows the device operation in the THz range.…”

Section: Results: Output Current Responsivity and Tuningmentioning

confidence: 99%

Graphene nanoelectromechanical resonators for the detection of modulated terahertz radiation

Svintsov¹,

Leiman²,

Ryzhii³

et al. 2014

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Abstract. We propose and analyze the detector of modulated terahertz (THz) radiation based on the graphene field-effect transistor with mechanically floating gate made of graphene as well. The THz component of incoming radiation induces resonant excitation of plasma oscillations in graphene layers (GLs). The rectified component of the ponderomotive force between GLs invokes resonant mechanical swinging of top GL, resulting in the drain current oscillations. To estimate the device responsivity, we solve the hydrodynamic equations for the electrons and holes in graphene governing the plasma-wave response, and the equation describing the graphene membrane oscillations. The combined plasma-mechanical resonance raises the current amplitude by up to four orders of magnitude. The use of graphene as a material for the elastic gate and conductive channel allows the voltage tuning of both resonant frequencies in a wide range.

show abstract

Section: Results: Output Current Responsivity and Tuningmentioning

confidence: 99%

Graphene nanoelectromechanical resonators for the detection of modulated terahertz radiation

Svintsov¹,

Leiman²,

Ryzhii³

et al. 2014

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

show abstract

“…1,2 Particularly in the case of radio frequency devices and ultra low power sensor applications, ohmic contacts with resistivity in the range of 0.2-1 kΩµm are desirable. 3 Contact resistivity values as low as 200-500 Ωµm have been reported on exfoliated graphene and devices of small dimensions~100 nm).…”

Section: Introductionmentioning

confidence: 99%

Making consistent contacts to graphene: effect of architecture and growth induced defects

et al. 2016

View full text Add to dashboard Cite

The effect of contact architecture, graphene defect density and metal-semiconductor work function difference on resistivity of metal-graphene contacts have been investigated. An architecture with metal on the bottom of graphene is found to yield resistivities that are lower, by a factor of 4, and most consistent as compared to metal on top of graphene. Growth defects in graphene film were found to further reduce resistivity by a factor of 2. Using a combination of method and metal used, the contact resistivity of graphene has been decreased by a factor of 10 to 1200 ± 250 Ωµm using Palladium as the contact metal. While the improved consistency is due to the metal being able to contact uncontaminanted graphene in the metal on the bottom architecture, lower contact resistivities observed on defective graphene with the same metal is attributed to the increased number of modes of quantum transport in the channel.

show abstract

“…Throughout the years of graphene research, researchers have discovered various methods to reduce the contact resistance, including workfunction engineering [29,30], ultraviolet ozone treatment [31,32], alteration of the device geometry [33,34], and improvement of the surface roughness of graphene [35]. However, these methods are all approaches to strengthen the metal adhesion to the graphene sheet while the device is in a top-contact structure, which is still limited by the weak van der Waals forces at the metal-graphene interface.…”

Section: Introductionmentioning

confidence: 99%

Approaches to Reduce the Contact Resistance by the Formation of Covalent Contacts in Graphene Thin Film Transistors

Han

Yeo

2017

Appl. Sci. Converg. Technol.

View full text Add to dashboard Cite

Graphene, with a carrier mobility achieving up to 140,000 cm 2 /Vs at room temperature, makes it an ideal material for application in semiconductor devices. However, when the metal comes in contact with the graphene sheet, an energy barrier forms at the metal-graphene interface, resulting in a drastic reduction of the carrier mobility of graphene. In this review, the various methods of forming metal-graphene covalent contacts to lower the contact resistance are discussed. Furthermore, the graphene sheet in the area of metal contact can be cut in certain patterns, also discussed in this review, which provides a more efficient approach to forming covalent contacts, ultimately reducing the contact resistance for the realization of high-performance graphene devices.

show abstract

Ultraviolet/ozone treatment to reduce metal-graphene contact resistance

Cited by 121 publications

References 29 publications

Graphene nanoelectromechanical resonators for the detection of modulated terahertz radiation

Graphene nanoelectromechanical resonators for the detection of modulated terahertz radiation

Making consistent contacts to graphene: effect of architecture and growth induced defects

Approaches to Reduce the Contact Resistance by the Formation of Covalent Contacts in Graphene Thin Film Transistors

Contact Info

Product

Resources

About