A Quantitative Study of CVD Graphene on Synthesis Parameters and Sheet Resistance

A Study on the Dynamic Tunning Range of CVD Graphene at Microwave Frequency: Determination, Prediction and Application

“…The measured results of the orthogonal experiment is shown in Figure 4, the tunning range of GSS composed of graphene sheets measured by waveguide method in group_4 is the largest, which varies from 430−1840 Ω/sq. Combining our previous work [26], it can be seen that the demands for growth parameters are consistent when pursuing the lowest static sheet resistance and the biggest tunning range of graphene. This can be understood by the best flatness and integrity of graphene sample grown under the parameter of group_4 as shown in Figure 5a.…”

“…The dynamic tunning range of graphene is measured through the waveguide method, as shown in Figure 2a, which is a kind of noncontact measurement method. It should be noted that the dynamic tunning range is unable to be measured by the commonly used four-probe method [17,26] because the conductive part (graphene) is wrapped by its transfer substrate. The waveguide used for measuring the dynamic sheet resistance of graphene is WR90 (8.2-12.4 GHz) and the vector network analyzer used is purchased from Agilent Co. Ltd., Santa Clara, CA, USA, (ZNB-40, 10-40 GHz).…”

“…Polynomial fitting with fitting order equaling 4 is selected after comparing with other fitting functions. The values of q i,j after optimization are shown in Table 3, and the value of q 0 is 2.8767 × 107, the optimization process can be found in [26]. The physical significance of the model can be understood from the following aspects.…”

“…The tunning range of graphene not only provides the basis for the simulation and design of these works but also serves as an important basis for experimental feasibility, but the tunning range of graphene in these works shows apparent differences, which causes doubts in researchers' minds and is not conducive to the further application of graphene in microwave devices. In our previous work [26], the relationship between growth parameters and static sheet resistance of graphene was simply introduced. Many researchers are also committed to the study of the synthesis and also the physicochemical properties of graphene [27,28].…”