Growth of two-dimensional TMDCs and MXene novel structures for high performance transistor applications

The properties of two-dimensional (2D) materials exhibit a high potential for the design of low-power, low-loss and high-performance active and passive devices aiming for next-generation electronics and photonics applications. However, there are still critical challenges to grow such 2D materials and fabricate their devices. In recent years, the two-dimensional transition metal dichalcogenides (TMDCs) have gained widespread interest due to their extraordinary electronic and optical properties. Molybdenum disulfide (MoS2) is currently seen as a promising "beyond-graphene" material for applications in two-dimensional next-generation electronics. Former studies have shown that glass usage during the growth process can improve the flake quality and surface uniformity. For device fabrication, these grown samples must be transferred onto Si/SiO2 substrate. To understand the effect of this additional step, temperature-dependent µ-Raman and photoluminescence measurements are performed in the range of 83 to 483 K. Peak positions of the first-order Raman modes are analyzed, thermal coefficients of the as-grown and transferred samples are calculated and then compared. Herein, also, an experimental investigation of Raman spectra of WS2 single layers grown on Si/SiO2 substrates is carried out within the range of 83 K to 483 K in order to demonstrate their sustainability under harsh conditions. The second part of this thesis is focused on Mo2C (molybdenum carbide), which is a member of the two-dimensional new chemical compound family called MXenes. Mo2C has drawn significant attention due to its potential applications in energy storage and sensing. Large surface coverage is a must for large area applications such as supercapacitors. In this study, flakes are produced with the chemical vapor deposition (CVD) method to obtain large surface coverage. Systematic set of experiments are performed in order to reveal the optimum growth parameters. Finally, the grown samples are characterized by optical microscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), and µ-Raman spectroscopy techniques.