RETRACTED ARTICLE: Large-Area Semiconducting Graphene Nanomesh Tailored by Interferometric Lithography
Authors: Seyedhamidreza Alaie
Sanjay Krishna
Noel Mayur Dawson
Javad Ghasemi
Alireza Kazemi
Xiang He
Steven R J Brueck
Francesca Cavallo
Terefe G Habteyes
Journal: Scientific Reports (2015)
Discipline: Multidisciplinary
Keywords: Graphene nanostructures; interferometric lithography; semiconducting graphene nanomesh; quantum confinement effects; lithographic technologies
Affiliations: Center for High Technology Materials, University of New Mexico, NM 87106, USA., 1] Center for High Technology Materials, University of New Mexico, NM 87106, USA [2] Department of Mechanical Engineering, University of New Mexico, NM 87131, USA., 1] Center for High Technology Materials, University of New Mexico, NM 87106, USA [2] Nanoscience and Microsystems Engineering, University of New Mexico, NM 87131, USA.

Abstract:  Graphene nanostructures are attracting a great deal of interest because of newly emerging properties originating from quantum confinement effects. We report on using interferometric lithography to fabricate uniform, chip-scale, semiconducting graphene nanomesh (GNM) with sub-10 nm neck widths (smallest edge-to-edge distance between two nanoholes). This approach is based on fast, low-cost, and high-yield lithographic technologies and demonstrates the feasibility of cost-effective development of large-scale semiconducting graphene sheets and devices. The GNM is estimated to have a room temperature energy bandgap of ~30 meV. Raman studies showed that the G band of the GNM experiences a blue shift and broadening compared to pristine graphene, a change which was attributed to quantum confinement and localization effects. A single-layer GNM field effect transistor exhibited promising drive current of ~3.9 μA/μm and ON/OFF current ratios of ~35 at room temperature. The ON/OFF current ratio of the GNM-device displayed distinct temperature dependence with about 24-fold enhancement at 77 K. 

Retracted: Yes

PubPeer comments:
 2021 retraction. https: www.nature.com articles s41598-021-84101-3 Retraction of: Scientific Reports https: doi.org 10.1038 srep11463, published online 01 July 2015 The Editors have retracted this article following an investigation by the University of New Mexico which established that: Figure 2A and 2G contain data points that cannot be substantiated; Figure 3A-F and the corresponding histogram data contain images in which contrast has been adjusted or other nonlinear image enhancements made, resulting in images that have smaller feature sizes than were actually present; The image shown in Figure S3E does not originate from the same sample as other panels in this figure; Figure S3E appears to also have been manipulated in a manner similar to Figure 3; The Raman spectral data in Figures. 4A-C are shifted along the X-axis to produce a systematic shift of the G-band with stated feature size. The spectral data shown in Figure 4C which depict a shift in the G-band peaks irrespective of location on the structures cannot be substantiated; Figures 5B and 5C, as well as the red curve in Figure 5D cannot be substantiated; In Table I, rows  Min Neck Width (nm) ,  ON OFF Ratio ,  Mobility (cm2 V.s) , and  Band gap (meV) in the column  Interferometric Litho cannot be substantiated; Figure 6 and Figure S5 cannot be substantiated. Sanjay Krishna, Francesca Cavallo and Steven R. J. Brueck agreed with the retraction and its wording. Alireza Kazemi and Terefe G. Habteyes did not respond to the correspondence about the retraction. The Editors were not able to obtain current email addresses for Xiang He, Seyedhamidreza Alaie, Javad Ghasemi, and Noel Mayur Dawson. ,