Publications

In the modern age of gas sensing technologies for broad applications such as internet of things, the capability to make selective, small form factor, and highly responsive sensors for applications such as wearable devices and cell phones could revolutionize the fields of gas sensing systems and fabrications. This thesis aims at developing a millimeter-sized and microwatt-powered sensor prototype using graphene field effect transistors (FETs) by exploring various DC and AC modulation techniques to realize the critical gas sensing features of selectivity and fast recovery speed at room...

Over the past decade, there has been rapidly growing interest in wearable and implantable devices for a wide range of biomedical applications. For many applications involving prolonged contact with the body, devices that are compliant and can comfortably conform to and move with the patient are highly preferred. These flexible substrates (i.e. clothing, bandages, meshes, catheters, etc) can be instrumented to measure various physiological markers, such as temperature, pH, and oxygenation levels, to better inform clinical care. In this dissertation, I will discuss two examples of...

The potential widespread usages of ultrasonic transducer technology have inspired the development of microelectromechanical systems (MEMS)-based devices. The research presented in this dissertation focuses on enhancing the performance of piezoelectric micromachined ultrasonic transducers (PMUTs) by devising innovative design structures, analytically deriving models to understand and optimize performance, and using these findings to demonstrate PMUT-based systems with increased capabilities. The ring-shaped PMUT is firstly introduced as a high-performance PMUT architecture, which is...