A catalytic alloy approach for graphene on epitaxial SiC on silicon wafers
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Citations
Production and processing of graphene and related materials
Ultrathin epitaxial graphite: 2D electron gas properties and a route toward graphene-based nanoelectronics
Graphene growth on silicon carbide: A review
Sustainable life cycles of natural-precursor-derived nanocarbons
Sustainable life cycles of natural-precursor-derived nanocarbons
References
Growth of 3C―SiC on 150-mm Si(100) substrates by alternating supply epitaxy at 1000 °C
Evolution of epitaxial graphene layers on 3C SiC/Si (111) as a function of annealing temperature in UHV
Structural coherency of epitaxial graphene on 3C–SiC(111) epilayers on Si(111)
Large area quasi-free standing monolayer graphene on 3C-SiC(111)
Orientation-dependent stress relaxation in hetero-epitaxial 3C-SiC films
Related Papers (5)
Measurement of the Elastic Properties and Intrinsic Strength of Monolayer Graphene
Frequently Asked Questions (15)
Q2. How many contacts were used in the analysis chamber?
Sheet resistance measurements were taken using four electrical contacts in a van der Pauw configuration on the corners of AU51 1 cm2 samples.
Q3. What is the reason why SiC(100) graphene is better than SiC(?
The reason why the SiC (100) template leads in their case to an even better graphene quality than SiC(111) could be related to the combination of a considerably higher tensile stress and higher surface defectivity of the latter epitaxial SiC as discussed in their previous work.
Q4. What was the base pressure in the analysis chamber?
The base pressure in the analysis chamber was below 1.0 10 8 Torr. Data analysis was performed with the CasaXPS software and a Shirley baseline with Kratos library relative sensitivity factors.
Q5. What was the ion milling technique used to remove Ga ion damage?
Subsequent Ar1 ion milling was conducted in a Fiscione NanoMill™ to remove Ga ion damage and provide a high resolution transmission electron microscope (HRTEM) foil.
Q6. What is the resistance of graphene on SiC(100)?
This sheet resistance corresponds to a resistivity of about 2 10 8 X m for the graphene, as low as bulk Au metal; (b) sheet resistance measured on the ;23 nm Ni/Cu alloy as a reference.
Q7. What is the RMS of graphene prepared with Ni?
Note that the graphene prepared with Ni/Cu indicates a 50% decrease in RMS as compared to the use of Ni alone as a catalyst, and that the graphene roughness does not seem dependent on the orientation of the starting substrate.
Q8. What is the main advantage of the graphene graphitization process?
This allows for a fast precipitation and graphitization of C released through the Ni silicidation reaction, leading to an extraordinary improvement in the uniformity and quality of the graphene obtained through Ni/Cu.
Q9. How much is the resistance of graphene on SiC?
By averaging measurements taken on five samples fabricated with the same graphitization procedure over separate runs, the authors can conclude that the sheet resistance of their bilayer graphene prepared on a SiC(100) layer with Ni/Cu is around 24.8 X/square 6 0.7 from sample-to-sample variation.
Q10. What is the Raman spectrum for graphene?
3. Example of Raman spectrum (graphene D, G, and 2D bands region) from graphene on SiC(100) prepared with ;8 nm Ni and ;15 nm Cu. Additionally to the low D over G band intensity, indicative of a good quality graphene, note that the 2D over G intensity ratio higher than 1 is indicative of a few-layer graphene.
Q11. What is the resistance of graphene to the underlying substrate?
preliminary results indicate that the adhesion of graphene to the underlying substrate could be an order of magnitude higher than the adhesion of a graphene layer grown ex situ and transferred onto a SiO2 layer on silicon.
Q12. How does the resistance of graphene be translated into a value?
for benchmarking purposes, it is meaningful to translate the sheet resistance of the bilayer graphene into a corresponding resistivity value by using the 0.9 nm thickness revealed by TEM.
Q13. What is the TEM thickness of the graphene?
Note that as TEM observation is extremely challenging, because of shadowing induced by the topography of the sample surface (;15 nm RMS, Table I) and the necessity for 20–30 nm thick metal layer deposition on the top of thesample (and thus of the graphene) for TEM preparation, it is not surprising that the nanolayer is not clearly visible along the whole cross-sectional image.
Q14. What is the ID/IG ratio of graphene on SiC(100)?
In fact, the ID/IG ratio of graphene on SiC (100) decreases from ;2 for 5 nm Ni catalyst alone to;0.8 when the Cu catalyst layer is added.
Q15. What is the adhesion value of graphene on SiC?
these preliminary measurements show that it is unlikely that the tested samples in Fig. 7(a) contained any interface with adhesion energies as low as 0.45 J/m2, which is the adhesion value reported in the literature for a monolayer graphene transferred onto a SiO2 layer.