Publications

Nanomaterials Processing Toward Large-scale Flexible/Stretchable Electronics

Toshitake Takahashi
Ali Javey
Tsu-Jae King Liu
Liwei Lin
2013

In recent years, there has been tremendous progress in large-scale mechanically flexible electronics, where electrical components are fabricated on non-crystalline substrates such as plastics and glass. These devices are currently serving as the basis for various applications such as flat-panel displays, smart cards, and wearable electronics.

In this thesis, a promising approach using chemically synthesized nanomaterials is explored to overcome various obstacles current technology faces in this field. Here, we use chemically synthesized semiconducting nanowires (...

Microfluidic Modules for Enabling Point-of-Care Biopsy-based Cancer Diagnostics

Debkishore Mitra
Luke P. Lee
Shuvo Roy
Lee W. Riley
2013

The analyses of patient tumor biopsy samples and biopsy-based diagnostics have emerged as important tools for cancer diagnostics. However, the techniques employed currently are restricted to centralized laboratories as they are time-consuming, manual labor intensive and vary considerably in their effectiveness amongst institutions and countries. Point of Care testing (POCT) for cancer with the capacity for multiplexed detection of numerous biomarkers in biopsy samples in a rapid, precise and portable manner is emerging as an area with enormous potential to disseminate universal...

Copper Oxide by Thermal Oxidation for Electrochemical Cells and Gas Sensors

Kevin Limkrailassiri
Liwei Lin
Costas Grigoropoulos
Roya Maboudian
2013

Advances in electrolytic and gas sensing technologies continue to be driven by careful selection and engineering of materials. Copper oxides—both cuprous oxide, Cu2O, and cupric oxide, CuO—are abundant, environmentally friendly, and highly versatile. An attractive feature unique to both copper oxides is the ease of synthesis through a one-step thermal oxidation of copper foil in ambient environment, yielding various oxide compositions and morphologies according to the oxidation temperature and time. There are many possible applications for the copper oxide...

Harsh Environment Silicon Carbide UV Sensor and Junction Field-Effect Transistor

Wei-Cheng Lien
Albert P. Pisano
Tsu-Jae King Liu
Elad Alon
2013

A harsh environment can be defined by one or more of the following: High temperature, high shock, high radiation, erosive flow, and corrosive media. Among all the harsh environment applications, high temperature applications have drawn lots of attention due to the emerging activity in automotive, turbine engine, space exploration and deep-well drilling telemetry. Silicon carbide has become the candidate for these harsh environment applications because of its wide bandgap, excellent chemical and thermal stability, and high breakdown electric field strength. This dissertation details...

High-Resolution μECoG: Design, Fabrication, and Applications

Peter Ledochowitsch
Michel M. Maharbiz
Jose M. Carmena
Robert T. Knight
Christoph E. Schreiner
2013

Since the early 1950s, electrocorticography (ECoG), the measurement of electrical po- tentials on the surface of the brain has become an invaluable tool in neurosurgery for the localization of epileptic foci before resection. The ECoG electrodes used in clinical practice are made in an archaic serial process that involves hand-soldering wires to a stiff, coarse grid of electrodes with a spatial resolution >1 cm, and a tangle of transcranial wires. In this thesis we report a modern microfabrication process based on photolithographic pat- terning of...

Aluminum Nitride Sensors for Harsh Environments

Fabian Goericke
Albert P. Pisano
Tsu-Jae King Liu
Liwei Lin
2013

Harsh environment applications include high temperature, pressure and mechanical shock. Aluminum nitride is a strong ceramic material with very good high temperature survivability. It also has piezoelectric properties that can be used for sensing applications and it can be deposited with good control as thin polycrystalline film for the fabrication of micro-electromechanical systems. In this dissertation, optimized deposition parameters for aluminum nitride films and characterization techniques for film stress gradients are investigated. Furthermore, two diff...

Microfluidic Reactors for the Controlled Synthesis of Nanoparticles

E. Yegan Erdem
Albert P. Pisano
Fiona M. Doyle
Liwei Lin
Tsu-Jae King Liu
2013

Nanoparticles have attracted a lot of attention in the past few decades due to their unique, size-dependent properties. In order to use these nanoparticles in devices or sensors effectively, it is important to maintain uniform properties throughout the system; therefore nanoparticles need to have uniform sizes or monodisperse. In order to achieve monodispersity, an extreme control over the reaction conditions is required during their synthesis. These reaction conditions such as temperature, concentration of reagents, residence times, etc. affect the...

Engineering Collective Behaviors

Daniel Cohen
Michel M. Maharbiz
Tejal Desai
Evan Variano
2013

Much of the world consists of many small things, animate or inanimate, interacting with each other to produce something larger than, and different from themselves. Comprising murders of crows, armies of ants, schools of fish, dunes of sand, and various organs in your body, the collective behaviors of these systems embody a different approach to engineering than we currently employ. This thesis explores three examples where principles from collective behaviors are deployed as engineering tools. The first example presents how the collective phenomenon of ‘percolation’ can be leveraged...

A Study of Mass Transport Towards the Design and Characterization of an Artificial Kidney

Peter Soler
Dorian Liepmann
Susan Miller
David B. Graves
Mohammad Mofrad
2014

This dissertation focuses on the design, fabrication, and study necessary for a renal cell device that mimics the bioreactor component of a bioartificial kidney. The motivation behind the project is to further the development toward an implantable bioartificial human kidney that will improve the quality of life for end stage renal disease (ESRD) patients. The bioartificial kidney system contains two units: i) a hemofilter based upon nanoporous silicon membranes, and ii) a bioreactor composed of kidney proximal tubule (PT) cells. The Roy group has pioneered work in membranes that have...

Thermal Ground Plane for Chip-Level Electronics Cooling

Hongyun So
Albert P. Pisano
Liwei Lin
Tsu-Jae King Liu
2014

The three-dimensional thermal ground plane was developed in response to the needs of high-power density electronics applications in which heat must be removed as close to the chip surface as possible. The novel design for this planar cooling device was proposed with three key innovations in the evaporator, wick, and reservoir layer, which provided enhanced and reliable cooling performance without wick dryout and back flows. For the evaporator and reservoir layer, a combination of a tapered channel and a triple-spike microstructure was designed to break up the pinned meniscus at the...