Ultra-Wideband Capacitive Micromachined Ultrasonic Transducers (CMUTs) and Through-Wafer Interconnects for Applications in Immersion and Air
Citation
Adelegan, O. J. (2020). Ultra-wideband capacitive micromachined ultrasonic transducers (CMUTs) and through-wafer interconnects for applications in immersion and air [Doctoral dissertation, North Carolina State University].
- Capacitive Micromachined Ultrasonic Transducers (CMUTs)
- Ultra-Wideband
- Immersion and Air Applications
- Acoustic Angiography
- Through-Wafer Interconnects
- 2D CMUT Arrays
- Silicon-Through-Glass-Vias (Si-TGV)
- Copper-Through-Glass-Via (Cu-TGV) Interconnects
- Sacrificial Release Process
Brief
This dissertation explores the design and fabrication of ultra-wideband capacitive micromachined ultrasonic transducers (CMUTs) for use in immersion and air, along with methods for their integration with supporting electronics.
Summary
This 2020 dissertation, "Ultra-Wideband Capacitive Micromachined Ultrasonic Transducers (CMUTs) and Through-Wafer Interconnects for Applications in Immersion and Air," by Oluwafemi Joel Adelegan, explores the use of capacitive micromachined ultrasonic transducer (CMUT) technology in developing ultrasound devices. The dissertation focuses on the creation of CMUTs with wide-band capabilities for use in both immersion and air.
The dissertation is divided into seven chapters. Chapter 1 introduces the motivation for the research, emphasizing the need for transducers with broad bandwidth capabilities in various ultrasound applications. The second chapter focuses on the development of high-frequency ultra-wideband 1D CMUT arrays for acoustic angiography, which requires transducers capable of transmitting at low frequencies and detecting scattered echoes at higher harmonics. Chapter 3 discusses the design and implementation of wideband CMUTs specifically for airborne applications. Chapter 4 and 5 detail the process of fabricating 2D CMUT arrays on insulating substrates. Chapter 4 focuses on arrays using copper-through-glass-via interconnects, while Chapter 5 focuses on arrays with silicon-through-glass-via interconnects. Chapter 6 outlines the fabrication of an 8-element annular CMUT array on a 2D CMUT canvas, showcasing the flexibility of CMUT technology in creating diverse array geometries. Lastly, chapter 7 concludes the dissertation, summarizing the research contributions and offering suggestions for future research directions.