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Since the discovery of graphene, two-dimensional (2D) materials have attracted intensive interests in the past 15 years and there has been a growing interest in exploring new materials beyond graphene, such as silicene, germanene, etc. Numerous papers have been published to demonstrate their extraordinary electronic, optical, biological, and thermal properties which render broad applications in various fields. However, the absence of band gap in graphene and silicene prohibits their uses in digital applications. This dissertation reviews recent progress on band gap opening based on mono- and bi- layer silicene and presents a new silicon atomic structure which exhibits a 0.17 eV bandgap. In addition, a feasible approach was first demonstrated and proposed to potentially achieve the industrial-scale production of our simulated structure. More broadly, this approach suggests a new path for growing any materials on different substrates without forming chemical bond between the interaction layers.Although the gapless character of graphene prohibits its use in digital applications, it is not a concern for Radio Frequency (RF) applications. This work also investigated the impact of defects to RF electronic properties of the 2D materials. Chemical vapor deposited Graphene (CVDG) was selected as an example and was measured using scanning microwave microscopy (SMM). In order to analyze the result, a numerical model of SMM was first developed using Electromagnetic Professional (EMPro). From the results, both conductivity and permittivity of defective graphene exhibit the frequency-dependency properties. Additionally, the model we proposed in this work can precisely characterize the correlation between conductivity and permittivity of any materials in nanoscale at RF level. |
