Graphene CVD Growth And Simulation Of Graphene Reconfigurable Antenna

In recent years,as graphene has been successfully prepared,its excellent electrical,optical,and mechanical properties have also been widely studied.These properties have made graphene a research hotspot in many fields.With the rapid development of modern information technology,the importance of antennas in the communication field has become more prominent.Applying the excellent and unique physical properties of graphene to antenna design and preparation can effectively improve the performance of the antenna and promote the development of the wireless communication field.This thesis mainly conducts innovative research on the chemical vapor deposition（CVD）growth of graphene materials and the design of a new type of graphene reconfigurable antenna:（1）According to the theoretical calculation formula of graphene conductivity and relative permittivity,combined with computer programming,the conductivity and permittivity tunability of graphene are calculated,and the influence of chemical potential and frequency on the electromagnetic parameters of graphene is explored,and provide a data basis for the modeling of the graphene material in the antenna.From the perspective of graphene material growth,chemical vapor deposition is used to synthesize graphene films,and the influence of various parameters of the chemical vapor deposition process on the synthesis of graphene films is studied.Finally,we choose 300 min growth time,12min polishing time,and 1 sccm CH₄ flow rate.Single-layer,double-layer,and multi-layer graphene films are grown using a copper foil box as a substrate using chemical vapor deposition.Then,the graphene grown by chemical vapor deposition was subjected to PMMA wet transfer,and the transferred graphene was characterized by metallographic microscope and Raman spectroscopy.Under suitable growth parameters,a single-layer graphene film with a size of about 100μm can be obtained.（2）Using the physical properties of single-layer graphene with adjustable conductivity,graphene is applied to the design of microstrip dipole antennas,and a graphene-based material reconfigurable frequency antenna and pattern reconfigurable antenna are designed.The designed frequency reconfigurable antenna is located in the terahertz frequency band,and the graphene layer is located between the antenna radiator and the silicon substrate.Changing the chemical potential applied on the graphene can make the resonant frequency dynamic and reproducible in the range of 2.12～2.19 THz.Structure.The designed directional pattern reconfigurable antenna is located in the microwave frequency band.Graphene is used as the reflector and director of the antenna.The resonant frequency of the antenna is about 25 GHz.By adjusting the graphene chemical potential,the peak gain of the antenna can be changed from 3.5 d Bi to 5.56 d Bi.The front-to-rear ratio varies from 1.59 d B to 7.62 d B,and the gain and front-to-rear ratio increase significantly.The results effectively verified the feasibility of graphene materials used in frequency reconfigurable and directional reconfigurable antennas.