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Title: Chemical-free n-type and p-type multilayer-graphene transistors

Authors:
;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1283420
Grant/Contract Number:
SC0012704
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Applied Physics Letters
Additional Journal Information:
Journal Volume: 109; Journal Issue: 5; Related Information: CHORUS Timestamp: 2016-12-26 03:20:15; Journal ID: ISSN 0003-6951
Publisher:
American Institute of Physics
Country of Publication:
United States
Language:
English

Citation Formats

Dissanayake, D. M. N. M., and Eisaman, M. D.. Chemical-free n-type and p-type multilayer-graphene transistors. United States: N. p., 2016. Web. doi:10.1063/1.4960530.
Dissanayake, D. M. N. M., & Eisaman, M. D.. Chemical-free n-type and p-type multilayer-graphene transistors. United States. doi:10.1063/1.4960530.
Dissanayake, D. M. N. M., and Eisaman, M. D.. 2016. "Chemical-free n-type and p-type multilayer-graphene transistors". United States. doi:10.1063/1.4960530.
@article{osti_1283420,
title = {Chemical-free n-type and p-type multilayer-graphene transistors},
author = {Dissanayake, D. M. N. M. and Eisaman, M. D.},
abstractNote = {},
doi = {10.1063/1.4960530},
journal = {Applied Physics Letters},
number = 5,
volume = 109,
place = {United States},
year = 2016,
month = 8
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1063/1.4960530

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  • A single-step doping method to fabricate n- and p-type multilayer graphene (MG) top-gate field effect transistors (GFETs) is demonstrated. The transistors are fabricated on soda-lime glass substrates, with the n-type doping of MG caused by the sodium in the substrate without the addition of external chemicals. Placing a hydrogen silsesquioxane (HSQ) barrier layer between the MG and the substrate blocks the n-doping, resulting in p-type doping of the MG above regions patterned with HSQ. The HSQ is deposited in a single fabrication step using electron beam lithography, allowing the patterning of arbitrary sub-micron spatial patterns of n- and p-type doping.more » When a MG channel is deposited partially on the barrier and partially on the glass substrate, a p-type and n-type doping profile is created, which is used for fabricating complementary transistors pairs. Unlike chemically doped GFETs in which the external dopants are typically introduced from the top, these substrate doped GFETs allow for a top gate which gives a stronger electrostatic coupling to the channel, reducing the operating gate bias. Overall, this method enables scalable fabrication of n- and p-type complementary top-gated GFETs with high spatial resolution for graphene microelectronic applications.« less
  • In this paper, high-performance multilayer WSe 2 field-effect transistor (FET) devices with carrier type control are demonstrated via thickness modulation and a remote oxygen plasma surface treatment. Carrier type control in multilayer WSe 2 FET devices with Cr/Au contacts is initially demonstrated by modulating the WSe 2 thickness. The carrier type evolves with increasing WSe 2 channel thickness, being p-type, ambipolar, and n-type at thicknesses <3, ~4, and >5 nm, respectively. The thickness-dependent carrier type is attributed to changes in the bandgap of WSe 2 as a function of the thickness and the carrier band offsets relative to the metalmore » contacts. Furthermore, we present a strong hole carrier doping effect via remote oxygen plasma treatment. It non-degenerately converts n-type characteristics into p-type and enhances field-effect hole mobility by three orders of magnitude. Finally, this work demonstrates progress towards the realization of high-performance multilayer WSe 2 FETs with carrier type control, potentially extendable to other transition metal dichalcogenides, for future electronic and optoelectronic applications.« less
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  • Quasi-free-standing epitaxial graphene grown on wide band gap semiconductor SiC demonstrates high carrier mobility and good material uniformity, which make it promising for graphene-based electronic devices. In this work, quasi-free-standing bilayer epitaxial graphene is prepared and its transistors with gate lengths of 100 nm and 200 nm are fabricated and characterized. The 100 nm gate length graphene transistor shows improved DC and RF performances including a maximum current density I{sub ds} of 4.2 A/mm, and a peak transconductance g{sub m} of 2880 mS/mm. Intrinsic current-gain cutoff frequency f{sub T} of 407 GHz is obtained. The exciting DC and RF performances obtained in the quasi-free-standingmore » bilayer epitaxial graphene transistor show the great application potential of this material system.« less
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