Dissertation Defense

Graphene Transistor Based Nanoelectronic and Nanophotonic Applications

Che-Hung LiuPhD Candidate

Over the past few decades, electronics and photonics have been intensively and widely studied then applied due to their significant/tremendous impacts on every aspect of our daily life. Importantly, as the technology advanced and moving forward, the development of these applications not only relies on fundamental understanding but also requires novel materials with unique properties as well as new device architecture design in order to achieve even higher performance with more diverse functionalities. In this regards, nanoscale electronics and photonics exploiting nanomaterials' extraordinary characteristics is envisioned as a promising approach. Especially, low dimensional materials inherit properties that are conceptually different from those of bulk materials in all aspects. Therefore, the capability to tailor these nanomaterials and their unique properties is essential to achieve unconventional applications with revolutionary impacts. Here, our aim is to develop novel nanoelectronics and nanophotonics by exploiting the characteristics of purely two-dimensional (2D) monolayer graphene, where its remarkable electrical, optical properties have been widely and intensively studied since the first discovery in 2004. Firstly, we design the dual-gate graphene ambipolar transistor design that can operate as either common mode or differential mode amplifier, meanwhile, achieve high noise rejection amplification. Secondly, we propose the graphene-SOI heterojunction photodetector design to improve device on-off operation speed as well as strengthen the photo-gating effect, moreover, we fabricate these single pixels into matrix arrangement to achieve image array readout. Lastly, we demonstrate all-graphene transparent heterojunction photodetectors with high responsivity for proof-of-concept direct light-field ranging applications.

Sponsored by


Faculty Host

Prof. Zhaohui Zhang