Materials, Manufacturing, and Modeling

All faculty in IMG focus on the development or end-use of microelectromechanical systems (MEMS). Underpinning these efforts are fundamental research thrusts in materials synthesis and analysis; multiscale manufacturing; micro/nanofabrication and process integration; solid-state physics; and system simulation, modeling, design, and optimization.

Single-Input Control of Large Microrobot Swarms using Serial Addressing for Microassembly and Biomedical Applications

This collaborative research project will create a practical control scheme for large swarms of microrobots. These robots are typically no more than a few millimeters in length, and rely on an external power source and control signal. Currently, it is possible to steer the swarm as a whole to a single destination (or perhaps, to a desired average location). However, realizing the full potential benefits of microrobot swarms will require the ability to simultaneously send independent commands, either to individual robots or to small subgroups.

Magnetic Thick Films for Integrated Microwave Devices

This project is under DARPA's Magnetic Miniaturized and Monolithically Integrated Components (M3IC) program in the DARPA Microsystems Technology Office.

The objective of this effort is to develop thick-film magnetic materials that can be fabricated on semiconductor integrated circuits to enable highly miniaturized microwave components such as circulators and isolators operating in the 10 to 110 GHz frequency regime. These nonlinear, non-reciprocal components are critical for next generation radios, radar, and sensing systems for defense, consumer, automotive, and healthcare applications.

Large-area Manufacturing of Integrated Devices with Nanocomposite Magnetic Cores

As predicted by Moore's "law", the past few decades have seen massive reductions in the size of integrated circuits, enabling the portable, handheld devices now in everyday use. However, the components that power these devices have not experienced a similar size reduction. For example, the power adapter of a laptop computer is only modestly smaller than that two decades ago, and the printed circuit board inside a smart phone must dedicate between 20% and 40% of the board area for power conversion and management. To date, efforts towards miniaturization have been limited by both materials and manufacturing challenges. To address this gap, this research will study nanomanufacturing processes to facilitate the scalable synthesis of high quality magnetic nanoparticles and nanocomposite core materials and the fabrication of compact power inductors and transformers through assembly of these nanomaterials in a manner that is compatible with current manufacturing processes, such as silicon wafer or printed circuit board fabrication. This compatibility will enable fully integrated and compact system-on-chip or system-in-package power solutions. This research will be accomplished by fostering collaboration among disciplines including materials science, chemical engineering and electrical engineering. It will foster diversity in the profession by involving high school and undergraduate students in research activities and by broadening participation through the inclusion and engagement of women and underrepresented groups.

High Temperature Optical Sapphire Pressure Sensors for Harsh Environments

The primary objective of this research is to develop a high-bandwidth pressure sensor to provide benchmark, time-resolved, dynamic pressure data in high-temperature combustion environments. Specifically, these sensors will be designed to be embedded within a system and provide remote interrogation which will enable pressure to be measured in situ and on line under extreme conditions. Ultimately, this sensing technology will lead to better understanding and increased efficiency of complex power generation systems. In order to achieve this objective, research in sapphire laser micromachining and thermocompression bonding via spark plasma sintering technology will be conducted to enable fabrication of a fiber optic lever pressure sensor that uses a sapphire optical fiber for transduction of the pressure-induced diaphragm deflection. The proposed project will result in instrumentation-grade, high-temperature sensors that enable flush mounted measurements without sensor cooling. Furthermore, the use of optical techniques enables “passive” device operation, with electronics located remotely from the sensor. After fabrication and packaging, the pressure sensor will be rigorously characterized in acoustic plane wave tubes under both ambient and high-temperature conditions to determine its performance as a quantitative measurement device.

A Flush-Mount Piezoelectric MEMS Microphone for Aeroacoustic Flight Testing Applications

In their effort to locate, understand and mitigate the impact of noise sources on an aircraft, aeroacousticiansare in need of a high performance, low cost microphone to combat the increasing noise restrictions on commercial aircraft. Existing commercial sensors, even with their relatively high cost, in some cases constrain the quality and type of measurement that may be achieved. One such constraint is that the physical size and characteristics of the sensors limit the optimal locations in which the sensors may be placed. Previous generations of MEMS aeroacoustic microphones have failed to address the need for a sensor that can be packaged and installed with a smooth front surface to be used for boundary layer measurements in a fuselage array at cruise conditions. Additionally, these microphones must meet demanding requirements, including the sensing of high sound pressure levels (>160 dB) with low distortion (<3%) and high sensitivity stability (with respect to moisture and freezing) over temperatures from -60°F to 150°F. This work addresses the limitations of existing MEMS piezoelectric microphones used in aeroacoustic applications by incorporating through-silicon vias(TSVs) into the fabrication to eliminate the use of wirebondsthat affect the flow field and create an overall flush-mount microphone package.

Directed Nanoparticle Assembly by Electrophoretic Deposition

This industry-sponsored project is funded by the MIST Center. The specific details of this project are confidential.

 

The Multi-functional Integrated System Technology (MIST) Center is an NSF Industry/University Cooperative Research Center (I/UCRC) led by the University of Florida and the University of Central Florida. Our mission is to facilitate integration of novel materials, processes, devices, and circuits into multi-functional systems through research partnerships between university, industry, and government stakeholders. With ~30 faculty participants from 6 different departments, the MIST Center serves as an early-stage research sandbox for developing next-generation smart systems in the Internet of Things era.

High-Performance CoPt Micromagnets

This industry-sponsored project is funded by the MIST Center.  The specific details of this project are confidential.

 

The Multi-functional Integrated System Technology (MIST) Center is an NSF Industry/University Cooperative Research Center (I/UCRC) led by the University of Florida and the University of Central Florida. Our mission is to facilitate integration of novel materials, processes, devices, and circuits into multi-functional systems through research partnerships between university, industry, and government stakeholders. With ~30 faculty participants from 6 different departments, the MIST Center serves as an early-stage research sandbox for developing next-generation smart systems in the Internet of Things era.

Processes for Manufacturing High-Performance Magnetic Materials in Electronic Systems

The objective of this research is to develop new manufacturing processes for the magnetic components used in modern electronic systems. The goal is improve the manufacturability, performance, and energy efficiency of power supplies and communication devices, while simultaneously reducing their size and weight. A novel process is used to combine the properties of two different magnetic materials by embedding magnetic particles of one type of material inside of a second material. The result is a new, hybrid magnetic material that exhibits improved material properties compared to existing materials. In the long run, these new magnetic materials are aimed to enable next-generation mobile electronics, communication systems, robotics, and medical devices. The project will strengthen an industry/university research partnership between the University of Florida and Electron Energy Corporation via technical exchange and a graduate student summer internship. The project also aims to broaden participation and retention of female and minority students in STEM career fields.

Ultrashort Pulsed Laser Micromachining of Sapphire Sensors for High Temperature Environments

 

As engineers seek to design more efficient gas turbines, they require a detailed understanding of fundamental thermal-fluid phenomena, as well as active control methods, in high-temperature environments. The high-temperature requirement is based on the increasing turbine inlet temperatures, which have risen to 1500 C, in combined cycle systems in order to improve turbine peak power and efficiency. The limited survivability of silicon-based MEMS sensors in high-temperature and harsh environments has caused researchers to investigate other materials for high-temperature MEMS-based sensors; more specifically sapphire.

 

Sapphire’s material properties make its entry into the world of high temperature sensors promising, but it also renders most traditional MEMS manufacturing methods impractical. Sapphire’s chemical inertness does not allow for effective dry or wet etching; consequently, a more effective method of machining the material is necessary. One potential solution is to use laser ablation, or material removal by vaporization due to localized heat input, to pattern the material. Femtosecond and picosecond pulsed lasers have shown the ability to reduce or eliminate the thermal damage issues of longer pulsed lasers. These lasers are classified as ultrashort pulse width because the duration of the pulse is so short that it does not allow for thermal conduction into the crystal lattice of the material.

Photoresponsive Polymers for Autonomous Structural Materials with Controlled Toughening and Healing

Our research goal is to develop photoresponsive shape memory polymers (SMPs) that incorporate cinnamic acid and cinnamylidene acetic acid which are able to undergo efficient photoreversible reactions when exposed to alternating wavelengths of light. The hope is that this reversible reaction will be used to actively cleave and reform covalent crosslinks to mitigate the propagation of damage though local fracture, achieve shape recovery for crack closure, and to ultimately reform crosslinks across the crack face to recover the strength of the original material.  Our current results have shown that we can produce 1200% increased toughness, recover the plastic deformation of the specimen following loading to return it back to its original dimensions and subsequently achieve 96% healing efficiency without the reformation of crosslinks in the polymer.  This work was featured live on CNN and various other news outlets.

This approach is novel in that using adaptation of the local stiffness to mitigate the propagation of damage followed by healing has not been studied in the literature; therefore this work has the potential to make significant advances in the design of autonomous structures and in the development of greater post-treatment measures concerning fractured areas. The effort from this research will ultimately provide methods to create materials that function and respond to damage; mimicking what some biological systems naturally do.