The correlation of epitaxial graphene properties and morphology of SiC (0001)

Guo, Yu‐Guo; Guo, Liwei; Huang, Jiao; Yang, Rong; Jia, Yue; Lin, Jingjing; Lü, Wei; Li, Z. L.; Chen, X. L.

doi:10.1063/1.4863796

Cited by 12 publications

(5 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure a,b shows the highly magnified AFM images of the surface morphology of MLG/SiC after the AlN film release and the back surface of the AlN films after release. Clear stripes with an average spacing of about 100–200 nm can be seen at the surface of the MLG/SiC substrate after the AlN film release (Figure a), which are the steps and terraces of the MLG/SiC after graphitization before the growth of the AlN films . Similar steps and terraces at the back surface of the AlN films after release are shown in Figure b, which indicate that those features inherit from the surface of the MLG/SiC substrate as the widths of terraces are the same and there is no nanocrack in the AlN films.…”

Section: Resultsmentioning

confidence: 74%

Growth Model of van der Waals Epitaxy of Films: A Case of AlN Films on Multilayer Graphene/SiC

Cao²,

Li³

et al. 2017

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

"Volmer-Weber" island nucleation and step-flow growth model are the classical processes of the conventional epitaxy of films. However, a growth model of van der Waals epitaxy (vdWE) of films is still not very well-documented. Here, we present an example of vdWE of AlN films on multilayer graphene (MLG)/SiC by hydride vapor phase epitaxy at a high temperature of 1100 °C and reveal the orientation relationship of AlN, MLG, and SiC as (0001)[1-100]||(0001)[1-100]||(0001)[11-20], which suggests that the vdWE heterointerface is not an usual covalent bond and no excessive strain during the growth process owing to the incommensurate in-plane lattices. Remarkably, zigzag cracks are formed because of the anisotropy of strain after the films are cooled down to room temperature, indicating that the growth model of vdWE is different from that of conventional epitaxy. It is a layer-by-layer epitaxy, and a planar substrate without a miscut angle is essential for obtaining single-crystalline films. Additionally, the films can be transferred to foreign substrates by direct mechanical exfoliation without any stressor layer. An ultraviolet photosensor device illustrates an example of III-nitride heterogeneous integration application. Our work demonstrates an excellent step toward the vdWE of varieties of compound films on 2D materials for the applications of transferrable heterogeneous integration in future.

show abstract

Section: Resultsmentioning

confidence: 74%

Growth Model of van der Waals Epitaxy of Films: A Case of AlN Films on Multilayer Graphene/SiC

Cao²,

Li³

et al. 2017

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…The role of SiC morphology on transport properties of graphene grown by silicon sublimation was discussed by several groups. [47][48][49] It has been reported that SiC step edge density, 50 step height, 51 and step bunching 52,53 give rise to graphene's resistance. The step edge resistivity in monolayer graphene was evaluated by scanning potentiometry in a scanning tunneling microscope 51 and later associated with the abrupt variation in potential and doping due to detachment of graphene from the substrate as it passes over a step.…”

Section: Introductionmentioning

confidence: 99%

Step-edge-induced resistance anisotropy in quasi-free-standing bilayer chemical vapor deposition graphene on SiC

Ciuk

Çakmakyapan

Özbay

et al. 2014

Journal of Applied Physics

View full text Add to dashboard Cite

The transport properties of quasi-free-standing (QFS) bilayer graphene on SiC depend on a range of scattering mechanisms. Most of them are isotropic in nature. However, the SiC substrate morphology marked by a distinctive pattern of the terraces gives rise to an anisotropy in graphene's sheet resistance, which may be considered an additional scattering mechanism. At a technological level, the growth-preceding in situ etching of the SiC surface promotes step bunching which results in macro steps ∼ 10? nm in height. In this report, we study the qualitative and quantitative effects of SiC steps edges on the resistance of epitaxial graphene grown by chemical vapor deposition. We experimentally determine the value of step edge resistivity in hydrogen-intercalated QFS-bilayer graphene to be ∼ 190? Ωμ m for step height hS? =? 10? nm and provide proof that it cannot originate from mechanical deformation of graphene but is likely to arise from lowered carrier concentration in the step area. Our results are confronted with the previously reported values of the step edge resistivity in monolayer graphene over SiC atomic steps. In our analysis, we focus on large-scale, statistical properties to foster the scalable technology of industrial graphene for electronics and sensor applications. © 2014 AIP Publishing LLC

show abstract

“…The Raman spectra of BLG with the monolayer concentration of deposited F4-TCNQ molecules clearly exhibit the strong Raman peaks corresponding to F4-TCNQ molecules along with the characteristic peaks of graphene (G, 2D, and D peaks) and 6H–SiC (0001). − The peaks centered at around 1276, 1397, 1449, 1645, 2218, and 2897 cm –1 are associated with F4-TCNQ molecules. , In particular, the peaks centered at 1449 cm –1 and 1645 cm –1 correspond to the exocyclic CC stretch and endocyclic (or ring) CC stretch of F4-TCNQ, respectively. The peak centered at 2218 cm –1 is assigned to the stretching mode of the CN triple bond of F4-TCNQ molecules.…”

Section: Resultsmentioning

confidence: 98%

F4-TCNQ on Epitaxial Bi-Layer Graphene: Concentration- and Orientation-Dependent Charge Transfer at the Interface

et al. 2022

View full text Add to dashboard Cite

Bi-layer epitaxial graphene (BLG) on 6H–SiC(0001) (EG/SiC) was grown and modified by thermal deposition of the molecular electron acceptor tetrafluoro-tetra cyano quinodimethane (F4-TCNQ). The surface-modified system, F4-TCNQ/EG/SiC, was studied by X-ray photoelectron spectroscopy (XPS) and angle-resolved polarized Raman spectroscopy (ARPRS). XPS results indicate that bonding of deposited F4-TCNQ molecules depends on their concentration. Although bonding through the cyano groups is present at all concentrations, charge transfer from graphene to fluorine is evident only at sub-monolayer concentrations. The corresponding change in bond character is coupled with a change in molecular orientation. Raman spectroscopy not only provides results consistent with the findings from the XPS study but also reveals a significant degree of molecular stacking above the monolayer concentration. Thus, both the variation of the acceptor concentration and the number of graphene layers provide further handles to manipulate charge and doping that may be useful in device applications.

show abstract

The correlation of epitaxial graphene properties and morphology of SiC (0001)

Cited by 12 publications

References 46 publications

Growth Model of van der Waals Epitaxy of Films: A Case of AlN Films on Multilayer Graphene/SiC

Growth Model of van der Waals Epitaxy of Films: A Case of AlN Films on Multilayer Graphene/SiC

Step-edge-induced resistance anisotropy in quasi-free-standing bilayer chemical vapor deposition graphene on SiC

F4-TCNQ on Epitaxial Bi-Layer Graphene: Concentration- and Orientation-Dependent Charge Transfer at the Interface

Contact Info

Product

Resources

About