Transcript Smart MEMS-based and Piezoelectric Medical Devices

SMART Piezoelectric&MEMS-based
Devices/Applications
An NGUYEN-DINH
[email protected]
www.vermon.com
MEMs-based imaging device for the diagnostic of arthritic diseases.
This work is funded under FP7 programme « IACOBUS », EC Grant Agreement 305760 / HEALTH2012.1.2-1
Contact: Nicolas SENEGOND
[email protected]
Outlook
• IACOBUS project (European FP7 funding program) : Diagnosis and monitoring of Inflammatory and
Arthritic diseases using a COmbined approach Based on Ultrasound, optoacoustic and hyperSpectral
imaging
(project coordinator : Fraunhofer IBMT)
• Objective: improvement of the diagnosis of arthritis
Development of a 3D imaging system combining photoacoustics & echographic for finger joint imaging.
• Development of the ultrasound system, laser sources & reconstruction algorithm (Fraunhofer IBMT)
• Development of the smart multi-modality ultrasonic probe (VERMON)
Specifications
Geometry
• 4 Tile portions :
• 2 « Grand Tiles » of 30mm RoC including 256 trx channels
• 2 « Small Tiles » of 15mm RoC including 128 trx channels
• TRX maximum thickness = 6 mm
• Translation of the 4 arcs for 3D reconstruction
Transducer
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Central frequency 10-12 MHz
Inter-element pitch 150 µm
Elevation H = 3 mm
Transverse focus = 12 mm
Mechanical design
Translation axes
• General view
• Probes are entirely immersed in a water tank
• Material used for housing : anodised aluminum
• Maximum thickness of each Tile: 6 mm
Water tank
Laser sources
Finger holder
Finger spacer
Mechanical design (1/2)
Preamp boards
• “Grand Tiles”
• 8 x 32 (256) element array cMUT
• 4 x 64 (256) channels pre-amp PCBs per Tile
• Coax cable for 256 channel driving + cable for preamp supplying and bias voltage for cMUTs
32 element cMUT array
Mechanical design (2/2)
• “Small Tiles”
• 4 x 32 (256) element array cMUT
• 2 x 64 (256) channels pre-amp PCBs per Tile
• Both Tiles are connected together with a single 256 coax cables
32 element cMUT array
Pre-amp PCB
capacitive Micromachined Ultrasonic
Transducer (cMUT)
Features
A Multiscale Device :
300 µm
40 mm
CMUT device
20 µm
CMUT element
Reversible Operations:
Ultrasonic wave
Movable electrode
CMUT cell
Ultrasonic wave
Vacuum gap
∆c
∆u
Transmit mode
Vdc+
Vac
∆u
Receive mode
Vdc
cMUT design
BW & central frequency simulation
Directory simulation
• Batch of simulations (FDM taking into account
mechanical, electrostatic & acoustic)
• Layout design of the masks of photolithography
• Process used : sacrificial layer process
• Wafers processed by specialised MEMS foundries
CAD design
Wafer fabrication
Characterization
Dimensioning control
Z-Profile measurement
Impedance measurement
Pre-amp circuitry design
8 channel preamplifier chipset
Connection with flex
Preamp-board
Top view
• 1 board = preamplification of 64 channels
• Sizes 12,5 mm*153 mm
• Thickness of the board 0,8 mm
• Thickness with electronic components = 2,65 mm
Power supply box
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3 channels power supply box
Provide DC voltages for preamplifier and bias voltages for cMUTs
Connection with probes : LEMO 14 points
Passive components
Bottom view
Connectors to cable
Integration
• Singulation of the 32 elts cMUT chips from wafer
• Test of devices : pulse echo measurement in oil
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BW, central frequency are characterized
• Interconnection : wirebonded on flexible board
• Packaging of cMUT chips: silicone rubber (<500µm)
compatible with ultrasonic propagation
• Direct assembly on to pre-amp PCBs (pad/pitch:
75µm/75µm)
Current statement
• Ultrasound Probe with optical mounting available for end 2014.
• First imaging prototype system available early 2015
• Preclinical test on 60 patients planned to start mid 2015
Low frequency vibrational Piezoelectric Energy Harvesters (PEH)
Contact: Guillaume FERIN
[email protected]
Energy Piezo-Harvester
Main piezoelectric harvesting technics
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Vibrations are everywhere and free
Direct Stress/Strain energy harvesting
Indirect external Vibrational harvesting using
inertial forces
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D31 mode
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D33 mode
DuraAct Patch Transducer - PI
VERMON - Advanced Research Dpt
State-of-the-art
204Hz
• D31 oriented unimorph, Multilayered
serial or parallel bimorph
• D33 interleaved unimorph & bimorph
• Possible integration forms
• MEMS
• Macro device
Jeong 2005 : d33 PZT Cant.
1.3KHz
Cantilever (clamped/free) beams
Bridges (clamped/clamped)
Spirals
Others
608Hz
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FANG 2006 : d31 PZT Cant.
200Hz
• Common topologies
Marzecki 2005 : d31 AlN Cant.
Marzecki 2007 : d31 AlN Cant.
200Hz
• Common flexural architectures
13.9KHz
Topologies for Vibrational Energy Piezoelectric Harvesters.
Renaud 2007 : d31 PZT Cant.
Dong 2008 : Spiral d31 PZT
Fabrication
X50
Surface roughness (PZT)
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Optical Thickness control
Poling and electrode plating
Bulk PZT
Metallic shim material
Advanced Polymer bonding
CONFIDENTIAL
VERMON - Advanced Research Dpt
Performance
Piezoelectric device impedance (with no tip mass)
100
Amplitude
Phase angle
80
60
40
1,00E+03
20
0
-20
1,00E+02
-40
(88.0Hz, 1.57MΩ)
(85.8Hz, 23kΩ)
-60
Imepdance phase angle (°)
Test bench for electrical impedance measurement and
harmonic mechanical solicitation
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W/WO Tip mass
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Clamping pressure monitored to avoid softening
effects
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Free circulating air (no softening recorded)
Impedance amplitude (kΩ)
1,00E+04
-80
1,00E+01
-100
80
82
84
86
88
90
92
94
frequency (Hz)
16
Polycrystalline PZT ceramic
PMN-PT [011] Single Crystal
14
RMS power (µW)
12
(With no Tip Mass)
10
8
6
4
1 G max uniaxial acceleration (gravity direction)
Electrical load 100kOhms
2
0
70
80
90
100
Harmonic excitation Frequency (Hz))
110
120
Medical Implants..
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Heart as a mechanical source
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Direct conversuin (external patchs)
Hear wall vibrational (external or internal
capsules
Power output
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>10µW continuous mean power delivery
Up to 2.5V mean voltage
Quality standards & requirements
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20-25 years durability
Comply with ISO60601 standards on active
implantable medical devices
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Key developments -Vibrational piezoelectric
energy harvester MUST be :
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Highly reliable
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“Implantable vibrational low Frequency
energy harvester”, VERMON
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No damageable
Long lifetime >25years
Highly efficient
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“Conformal piezoelectric energy harvesting
from motions of the heart, lung, and
diaphragm” C. Dagdeviren, 2014
Biocompatibility
Electrical safety
high power density
Works in every position
Great Integrability
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Miniaturization
Compatible with MEMS & CMOS process
SHM Applications..
• Vibrational piezoelectric
energy harvester MUST have :
• High reliability
• No damageable: Embedded in
structures if possible &
• Forget: Long lifetime >30years
• Harsh environment (-40/+50°C)
• Efficiency
• high power density or multiple
harvester hosting architectures :
Stackable PEH
• Works in every position (multiaxis approach)
• Cost : below battery costs
FAA Technical center, William J. Hugues
Embedded Autonomous Sensing
• General specifications
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Aircraft vibration source
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Harvesting frequency range from 10 to 50Hz
1 mm max displacement
1G max available acceleration
Goals : save maintenance costs
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Geometrical specs
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Flat enough to be embedded into composite
sandwiches between foams and skins
Compatible with internal composite
stress/strain
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10b$ a year for all airlines companies
35% could be saved with autonomous
sensors
Flaws detection and localization
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Passive acoustic or LRU sensors for guided
wave processing
Other inertial sensors
Autonomous acoustic sensor nodes