The University of Texas at Austin
Welcome to the MicroElectromagnetics Device Group
On-going research and teaching performed under the supervision of Dr. Dean P. Neikirk, Dept. of Electrical and Computer Engineering
last update: 01/12/07
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The University of Texas at AustinWelcome to the MicroElectromagnetics Device GroupOn-going research and teaching performed under the supervision of Dr. Dean P. Neikirk, Dept. of Electrical and Computer Engineeringlast update: 01/12/07 |
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| unique | days | time | room |
|---|---|---|---|
| 17425 | MWF | 09:00 - 10:00 | ENS 109 |
| unique | days | time | room |
|---|---|---|---|
| 16770 | MWF | 09:00 - 10:00 | ENS 109 |
| unique | days | time | room |
|---|---|---|---|
| 15765 | MWF | 10:00 - 11:00 | CPE 2.210 |
In several of these cases we have focused on electromagnetically coupled “resonant sensing tags,” ranging from passive RF tags for detection of damage in the civil infrastructure to micromachined fluidic chips that support chemical sensing. For use in chemical detection applications, “bead-based” chips have been developed that should allow compact, low-cost mulit-analyte chemical detection in a wireless tag. For civil structural health monitoring, a modification of existing electronic article surveillance (EAS) technology should produce extremely low cost devices capable of wireless transmission of information about the state of the underlying structure. In each case study we focus on the thread connecting one device to the next, and use this to illustrate how our direct collaboration with the end user (be they civil engineers, mechanical engineers, or chemists) dictates the final sensor configuration. Further details are discussed below. To construct these new structures we make extensive use of integrated circuit fabrication and micromachining techniques. We have developed and fabricated a wide range of sensors, including optically interrogated pressure sensors using micromachined Fabry-Perot cavities, and microminiature inductive proximity sensors. We have investigated the application of MEMS technology in such novel environments as mechanical bearings and fluid seals. As mentioned above, we are also working on an "electronic taste chip" for use in chemical and biological agent detection systems. The development of smart sensors capable of discrimination of multiple analytes has become increasingly important for real time diagnosis in medical applications; the electronic taste chips that have been developed should allow compact, low-cost multi-analyte chemical detection. Our sensor platform combines optical detection with microfluidics, novel photochemical sensing schemes, and molecular engineering of receptor sites. This work has been supported by the National Institutes of Health, as well as the Beckman Institute and the US Army Research Office. Another area of research for our group is the development of sensors for "structural health monitoring," including work on new passive RF tags for detection of damage in buildings and bridges that have been subjected to extreme conditions. We are investigating the use of simple, low cost wireless sensors to identifying material degradation in large civil structures (bridges and buildings) before actual failure of the structure. For example, the detection of corrosion in steel-reinforced concrete would be one application. For civil structural health monitoring, a modification of existing electronic article surveillance (EAS) and radio frequency identification (RFID) technology should produce extremely low cost devices capable of wireless transmission of information about the state of the underlying structure. The National Science Foundation and the Texas Advanced Technology Program have been key sponsors of this research. We are also interested in the electromagnetic design of rfid tags, and their modification to serve as sensors. The electromagnetic observability of RFID tags, and the implications of that observability on security and personal privacy, are areas under consideration. Our group has done extensive work on monolithic microwave, millimeter-wave, and terahertz (aka far infrared (FIR), submillimeter-wave, etc.) devices, in particular on planar antennas, FIR detectors, and microbolometers. Our original work focused on monolithic focal plane detector arrays to allow high resolution terahertz imaging. A primary focus in our current work is the design of micromachined infrared microbolometer detectors that exhibit enhanced spectral selectivity; with the goal of producing "color vision" in the infrared using multi-mode antenna arrays. The Microelectromagnetic Devices Group also combines knowledge of solid-state devices, IC fabrication, and electromagnetics, to help us understand high-speed signal propagation in integrated circuits, IC packages, and high-performance printed wiring boards. To explore high-speed and high-frequency signal behavior our group has developed a number of new models of lossy transmission lines and interconnects. To verify our models we also perform dc-to-microwave measurements on devices and interconnects. We are particularly interested in the impact of finite metal conductivity on interconnect characteristics, as well as the effect of substrate conductivity (e.g., semiconductor substrates) on signal propagation. Our models focus on the prediction of inductive and resistive effects, from dc resistance and internal inductance to skin-depth and proximity effect-dominated behavior, in both the frequency and time domains. We have done a variety of studies on planar inductors, including the effect of semiconductor substrate resistivity on integrated inductor behavior. A full understanding of these phenomena allow even complex propagation characteristics to be predicted in a simple manner, facilitating the design of devices such as coplanar waveguide phase shifters and delay lines. Similarly, constructing new devices and circuits that operate at extremely high frequencies requires the same combination of knowledge. In this context we have also investigated devices based on quantum interference effects. Our group developed several quantum transport models which were used to design heterostructure devices and, using the molecular beam epitaxial crystal growth technique, these devices were fabricated. These devices contained layers that are only a few atomic planes thick, causing very strong quantum interference. Originally these resonant tunneling devices (the QWITT diode, or quantum-well injection transit time diode) were investigated for use as high frequency oscillators, and were later studied for possible use as memory devices.
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If you have comments about this page, or would like further information, please contact Professor Neikirk at
neikirk@mail.utexas.eduThis page was last updated on January 12, 2007 .