Continuous Growth of Highly Reproducible Single-Layer Graphene Deposition on Cu Foil by Indigenously Developed LPCVD Setup

Abstract

Continuous growth of high-quality single-layer graphene (SLG) is highly desirable in several electronic and optoelectronic applications. To fulfill such requirements, we proposed a low-cost, highly reproducible high-quality SLG synthesized by indigenously developed low-pressure chemical vapor deposition (LPCVD) setup. The quality of SLG is examined by Raman spectroscopy, where we have probed the I 2D / I G ratio for continuous 30 runs to assess the reproducibility and quality of single-layer using proposed indigenous LPCVD setup for device fabrication. The highest I 2D / I G ratio of SLG (5.82) was found with full width at half maximum values of 2D peak and G peak of ∼30.10 cm −1 and ∼20.86 cm –1 , respectively. Further, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy have been performed to study the quality of SLG. Thickness measurement of graphene with graphene grain size is calculated from atomic force microscopy studies, and the average grain size is found to be 1–3 μm. Moreover, I – V characteristics have also been investigated by the two-probe method to ensure the quality of SLG. The lowest resistance of the SLG (∼387 Ω) was found at room temperature. Thus, this new indigenously developed low-cost setup provides a novel alternative method to produce highly reproducible metrology-grade continuous SLG on Cu substrate for next-generation quantum devices.

Partial Pressure Assisted Growth of Single-Layer Graphene Grown by Low-Pressure Chemical Vapor Deposition: Implications for High-Performance Graphene FET Devices

“…Here, the flow of hydrogen gas was maintained at a flow rate of 50 ± 1 sccm through the use of a mass flow meter, and flow of argon gas was maintained by a rotameter, as mentioned in our previously reported paper. 20 After controlling the desirable pressure inside the tube, heating was performed at a rate of 3° min –1 up to the temperature of 1050 °C. Hydrogen gas helps to reduce the thin oxide layer present on the copper surface, and argon acts as a carrier gas to activate the catalytic copper substrate.…”

“…Further, the quartz tube was evacuated to 1 Torr to maintain low pressure inside the quartz reactor, and finally, the mixture of hydrogen and argon gases was incorporated through one side of the tube. Here, the flow of hydrogen gas was maintained at a flow rate of 50 ± 1 sccm through the use of a mass flow meter, and flow of argon gas was maintained by a rotameter, as mentioned in our previously reported paper . After controlling the desirable pressure inside the tube, heating was performed at a rate of 3° min –1 up to the temperature of 1050 °C.…”

“… 13 − 15 Other metals also lead to formation of graphene, but multiple-layer formation or uniformity is the major issue with other catalysts. 13 − 20 CVD graphene is polycrystalline in nature because of coalescence of graphene nuclei formation and growth of these nuclei during synthesis by CVD. Coalescence of graphene grains results in formation of grain boundaries that act as scattering sites for charge carriers and degrade the quality of graphene.…”

“…Due to the self-limiting behavior of copper (Cu) and the less solubility of carbon in a copper substrate (<0.001 atom %), graphene growth is limited only to the surface of the copper substrate, which insists growth of uniform single-layer graphene (SLG). Hence, several research groups used copper as a catalyst to get SLG during the growth of graphene. − Other metals also lead to formation of graphene, but multiple-layer formation or uniformity is the major issue with other catalysts. − CVD graphene is polycrystalline in nature because of coalescence of graphene nuclei formation and growth of these nuclei during synthesis by CVD. Coalescence of graphene grains results in formation of grain boundaries that act as scattering sites for charge carriers and degrade the quality of graphene.…”

Electronically triggered tunable terahertz signal observed in LPCVD grown single layer graphene

“…23 As per the literature survey, low pressure chemical vapour deposition (LPCVD) is the most favourable method for high-quality, large area, and continuous growth of SLG which has been explored in this work. [24][25][26] In the present investigations, SLG has been synthesized using a low-cost and indigenously developed LPCVD setup. Furthermore, optical microscopy, field emission scanning electron microscopy and Raman spectroscopy techniques have been used to study the surface and structural morphologies of SLG.…”