Liwei Lin (Advisor)

Research Advised by Professor Liwei Lin

Lin Group:  List of Projects | List of Researchers

Selective Encapsulations of MEMS: Micro Channels, Needles, Resonators and Electromechanical Filters

Liwei Lin
Albert P. Pisano
Roger T. Howe
Van P. Carey
1993
Surface and combined surface/bulk micromachining techniques are developed for selectively encapsulated micro devices including micro flow channels, micro hypodermic needles, hermetically sealed lateral micro resonators and electromechanical filters. As part of...

Water-Powered Microfluidic Devices for Diagnostic and Drug Delivery Systems

Yu-Chuan Su
Liwei Lin
Albert P. Pisano
Luke P. Lee
2003
This dissertation presents the development of water-powered microfluidic devices, including actuators, pumps, pressure-sensitive valves, and flow discretizers, by integrating osmosis, capillarity, microfabrication, and polymer processing technologies at the microscale. By harvesting and coordinating the mechanical actuations driven by chemical potentials and interfacial forces, these water-powered devices can transport flows in pre-...

Electromagnetic Effects in MEMS Application: Actuators, Relay and Packaging

Andrew Cao
Liwei Lin
Albert P. Pisano
Luke P. Lee
2004
Two electromagnetic effects are utilized in MEMS applications: electromagnetic Lorentz force for bi-directional actuator/relay operations, and electromagnetic induction heating for MEMS bonding and packaging processes. As a proof-of-concept demonstration, a liquid-metal wetted contact process is developed to reduce the contact resistance in MEMS relay applications. Electromagnetic Lorenz force...

MEMS Microbial Fuel Cells and Photosynthetic Electrochemical Cells

Kien-Bang Lam
Liwei Lin
Albert P. Pisano
Kevin E. Healy
2005
In this dissertation, we present three MEMS (Micro-electro-mechanical Systems) biological electrochemical cells: (1) a microbial fuel cell (μMFC) utilizing glucose as the bio-fuel and live baker’s yeast as the bio-catalyst; (2) a photosynthetic electrochemical cell (μPEC1) based on unicellular bacteria Anabaena as the biological photo-electrical converter; and (3) a second photosynthetic electrochemical cell (μPEC2)...

Silicon Processed Microstructures Using Self-Aligned Plastic Deformation

Jongbaeg Kim
Liwei Lin
Albert P. Pisano
Luke P. Lee
2004

Two self-aligend plastic deformation processes are devleoped to fabricate silicon microstructures, including angular vertical comb-drives, scanning micromirrors, variable capacitors, and two-axial actuators based on global-furnace and localized-Joule heating methods. As a proof-of-concept demonstration, an ultrasonic packaging procedure that generates local plastic deformation of metallic bonding materials is also established for MEMS packaging applications.

Plastic defomation of silicon occurs at elevated temperature when silicon is stresses to a level higher than the reduced yield...

Piezoelectric Aluminum Nitride Vibrating RF MEMS for Radio Front-End Technology

Gianluca Piazza
Albert P. Pisano
Roger T. Howe
Liwei Lin
Kristofer S.J. Pister
2005
The demand of consumer electronics for RF filters and frequency reference elements has focused attention on the reduction of size, power consumption and price and pushed current research interests towards the manufacturing of a single-chip, integrated RF solution. Vibrating contour-mode MEMS resonators constitute the most promising technology for ultimately realizing this vision. This dissertation presents analytical and experimental results on a new class...

Localized Synthesis, Assembly and Integration of Silicon Nanowires

Ongi Englander
Liwei Lin
Albert P. Pisano
Oscar D. Dubon
2005
Localized synthesis, assembly and integration of one-dimensional silicon nanowires with MEMS structures is demonstrated and characterized in terms of local synthesis processes, electric-field assisted self-assembly, and a proof-of-concept nanoelectromechanical system (NEMS) demonstration. Emphasis is placed on the ease of integration, process control strategies, characterization techniques and the pursuit of integrated devices. A top-down followed by a...

Functional Gas Sensing Nanomaterials: A Panoramic View

Ritu Malik
Vijay K. Tomer
Yogendra Kumar Mishra
Liwei Lin
2020

The alarming rise of indoor pollution and the need to combat the associated negative effects have promoted increasing attention in modernizing the chemical sensing technologies by newly designed materials with rich and tunable functionalities at atomic or molecular levels. With the appealing physical, chemical, optical, and electronic properties for various potential applications, the state-of-art gas-sensing nanomaterials and their future perspectives are well-documented and summarized in this paper. Specifically, the key performance attributes are addressed in detail such as the...

A Multimodal Self-heating Flexible Seat Sensor for Heathcare Monitoring

Peisheng He
Yande Peng
Liwei Lin
2021

We report a self-healable, flexible, and multimodal sweat sensor based on laser-induced graphene electrodes for healthcare monitoring application. A transfer printing and laser engraving process has been developed to conduct a high-throughput patterning process of various materials on a self-healable substrate. The prototype device is capable of simultaneous detection of pH, uric acid, and tyrosine, which are important indicators for skin and metabolic disorders. Furthermore, this work has made advancements as compared with the state-of-art works: (1) maintaining sensitivity under large...

A Single Chip Directional Loudspeadker Based on PMUTS

Zhichun Shao
Sedat Pala
Yue Liang
Yande Peng
Liwei Lin
2021

This paper reports a highly directional air-coupled parametric loudspeaker using a single chip of piezoelectric micromachined ultrasonic transducers (pMUTs). Compared with the state-of-art technologies, three distinctive advancements have been achieved: (1) a micromachined parametric array based on CMOS-compatible bimorph AlN pMUTs; (2) generation of highly directional audible sound with a half power beam width less than 5 degrees; and (3) generation of multiple audible frequency using a single chip with 246 pMUT elements in a footprint of 13mm by 13mm. As such, the proposed AlN pMUT...