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.
Mark Sheplak's Research Group
The goal of this research is to develop a MEMS-based Five-hole Probe(5HP) that is able to measure the localized velocity vector (both the velocity magnitude and direction) and the static and dynamic pressure, in steady and/or unsteady flow fields. Five optical pressure sensors located on the hemisphere tip of the 5HP provide all information that is needed to resolve the flow. This 5HP is expected to be able to provide high spatial resolution, high frequency response and is compatible with elevated temperature environments. A primary focus of this research is on the microfabrication and micromachining of a die that incorporates five optical transducers and its successive packaging process. The completed sensors will be tested in flow cells and wind tunnels at UF for the final calibration.
John Rogers will defend his proposal entitled "A passive wireless MEMS dynamic pressure sensor with integrated temperature compensation for harsh environments" at 11:45 AM on Friday, October 9th, in Larsen 234.
Lunch will be provided for $3 to those who sign up on the IMG wiki (http://www.img.ufl.edu/wiki/index.php/IMG_Seminar_Series:_Fall_2015)
Jason June will defend his proposal entitled "An acoustic and hydrodynamic study of grazing flow over an acoustic liner" at 10:00 AM on Friday, May 22nd, in Larsen 234. Refreshments will be provided.
Casey Barnard will defend his proposal entitled "A flush-mount dual-axis differential capacitive MEMS shear stress sensor with through-silicon vias for wind tunnel applications" at 11:00 AM on Wednesday, May 6th, in Larsen 234. Refreshments will be provided.
IMG will present multiple papers at the Transducers 2015 conference in Anchorage, AK June 21-25, 2015. Congratulations to all authors!
- V. F. Tseng, L. We, and H. Xie, "Inductive eddy current sensing as a displacement sensing mechanism for large piston/rotation micromirrors" (oral)
- X. Zhang, R. Zhang, S. Koppal, L. Butler, X. Cheng, and H. Xie, "MEMS mirrors submerged in liquid for wide-angle scanning" (oral)
- X. Zhang, B. Li, and H. Xie, "A robust, fast electrothermal micromirror with symmetric bimorph actuators made of copper/tungsten" (oral)
- W. Wang, J. Chen, A. S. Zivkovic, C. Duan and H. Xie "A silicon based Fourier transform spectrometer based on an open-loop controlled electrothermal MEMS mirror" (oral)
- D. Mills, D. Blood, and M. Sheplak, “Development of a sapphire optical wall shear stress sensor for high-temperature applications” (poster)
- R.E. Carroll, N. Garraud, J.A. Little, M.J. Mazzoleni, B.P. Mann, and D.P. Arnold, "Investigation of wave propagation phenomena in microfabricated arrays of nonlinearly coupled oscillators” (poster)
- D. P. Arnold, "Electroplated CoPt Permanent Magnets for MEMS" (invited talk)
The NSF Multi-functional Integrated System Technology Center (MIST Center) held it’s Kickoff Meeting on Dec. 11-12, 2014. Led by IMG faculty Dr. Nishida and Dr. Arnold, and in partnership with UCF, the mission of the MIST Center 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 inaugural membership from eight organizations, the MIST Center selected 8 projects (6 at UF and 2 at UCF) to be conducted during 2015. The UF projects are:
- Directed Nanoparticle Assembly by Electrophoretic Deposition (PI: Dr. Arnold)
- Laser Micromachining of 3-D Miniature Parts in Hard Materials (PI: Dr. Sheplak)
- Technology Development for Harsh Environment Microsensors (PI: Dr. Sheplak)
- High-Performance CoPt Micromagnets (PI: Dr. Arnold)
- Compact Array Antennas with High Gain, Power Efficiency, and EMI Immunity in a System-in-Package Platform (PI: Dr. Yoon)
- Ferroelectric HfO2 for Energy Storage and Non-volatile Memory Applications (PI: Dr. Nishida)
David Mills will defend his dissertation "A sapphire MEMS-based optical shear stress sensor for high-temperature applications" at 11:00 am on Monday, November 10 in Larsen 234. Refreshments will be provided.
Tiffany Reagan will defend her dissertation proposal entitled "A flush-mount MEMS piezoelectric microphone with through-silicon-vias for aeroacoustic flight testing applications" at 12:00 pm on Wednesday, October 22 in LAR 234. Refreshments will be provided.
Per Export Administration Regulations, which apply to the content of the proposal defense (ECCN 9E991), no persons from a sanctioned or embagoed entity is permitted to attend. This includes citizens of Cuba, Iran, North Korea, Sudan and Syria.
We will hold an IMG Kickoff meeting on Friday August 22nd in Larsen 310, starting at 1 pm, immediately after our Friday BBQ. This meeting is mandatory for all IMG personnel. We will provide an overview of IMG to new students, review lab organization/training, emphasize importance of the wiki, and review safety information.