Heterogeneous Solid Carbon Source‐Assisted Growth of High‐Quality Graphene via CVD at Low Temperatures

Abstract

Polycyclic aromatic hydrocarbons (PAH) have been widely used as solid carbon sources for the synthesis of graphene at low temperatures. The inevitable formation of structural defects, however, has significantly limited the quality of the synthesized graphene. This article describes a low‐temperature chemical vapor deposition method that effectively mitigates defect formation in graphene by heterogeneous solid carbon sources containing a mixture of aromatic and aliphatic carbon on a Cu substrate. The addition of small amount of aliphatic carbon sources to the PAH significantly decreases the defect density of graphene synthesized at 400 ≤ T ≤ 600 °C by incorporating small aliphatic carbon fragments into defect sites. The carrier mobility of graphene grown using this heterogeneous solid carbon source is more than five times that of graphene synthesized using only PAH. Two mechanisms are also proposed by which vacancies can be generated during graphene growth using PAH sources on Cu, defect generation due to the disordered packing and the geometric limitation of PAH molecules. This low‐temperature method of synthesizing graphene reduces the degree of defect density using heterogeneous solid carbon sources promises to provide wide utility in electronics applications.

Review of the synthesis, transfer, characterization and growth mechanisms of single and multilayer graphene

“…Besides the aforementioned solid carbon precursors, coronene 30 and polycyclic aromatic hydrocarbon 31 demonstrated their potential in the synthesis of high-quality graphene, with a very weak or negligible D peak observed.…”

Graphene-based synthetic antiferromagnets and ferrimagnets

“…Regarding compatibility with device fabrication processes such as complementary metal-oxide-semiconductor (CMOS), the high CVD Gr growth temperature here used (i.e., 1300 K) exceed the thermal budget of CMOS manufacturing, being high enough to produce issues by diffusion or melting. Alternative graphene-growth methods such as plasma assisted 52 , CVD reactors 14 , or polycyclic aromatic hydrocarbons precursors 53 , 54 enable a significant reduction of graphene-growth temperatures (700–900 K). Alternatively, in past years an increasing number of solutions have been proposed for heterogeneous Gr-Si integration, employing the clean transfer of Gr grown on other supports directly onto SiO 2 /Si or silicon-on-insulator substrates 55 , 56 .…”

Near room temperature chemical vapor deposition of graphene with diluted methane and molten gallium catalyst

“…4b ). Moreover, the higher mobility of graphene grown by the Ga based CVD method is also compared with the CVD graphene grown on Cu and Fe foils 15 – 21 . One notes that the mobility value of graphene grown at low temperatures of 100 °C was not reported previously.…”

“…Microwave and/or plasma assisted CVD is also a possible way to activate the source decomposition at 400~600 °C 18 , 19 . Introduction of nuclei seeds such as coronene 20 and polycyclic aromatic hydrocarbon 21 seems to reduce the growth temperature blow 300 °C. However, the quality of such low-temperature synthesized graphene generally need further improvement.…”