SUMMARY

Introduction of novel semi-conducting materials with their unique material properties has opened the avenues for significant improvement in many electronic systems. For example, gallium oxide, with its ultra-wide bandgap, can help achieve higher breakdown voltages and switching efficiency, which makes it a promising candidate for next generation of RF and power electronics. Similarly, the carbon nanotubes (CNTs) with their superior electrical, thermal, and mechanical properties can help build low-power, transparent, flexible and wearable electronics. This work aims to study the transport characteristics of gallium oxide FETs and CNT network-based FETs. First, transport characteristics of a random CNT network-based FET were studied. Randomness of CNT networks is used to develop physically unclonable functions (PUFs). PUFs can enable a hardware based cryptographic technique to prevent unauthorized access of electronic devices. A new multi-gated CNT-FET design has been proposed, which can further enhance randomness and security of the PUF. In addition, this work has investigated the electro-thermal transport in β-Ga2O3 FETs using a combination of modeling and metrology techniques. Low thermal conductivity of β-Ga2O3 leads to self-heating in its FETs and heat dissipation poses a significant challenge for viability of these devices. Accurate prediction of the electrical and thermal characteristics of these devices is needed for efficient thermal management and device design. A TCAD device model and 3-D diffusive transport model has been developed to investigate the transport characteristics of these FETs. Ultrafast thermal imaging of the FETs has been performed using a thermoreflectance imaging system to understand the temperature rise at short time scales at different operating voltages. The device level passive thermal management techniques has also been investigated. Phonon BTE is used ballistic-diffusive thermal transport in β-Ga2O3 thin films and FETs.