Transcript LAAS_Capteurs_pression
PRESSURE / STRESS SENSORS
Patrick PONS, Philippe MENINI 5 phD, 1 post doc 1 RECIF Engineer November 2006
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INTRODUCTION
Objectives
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Development of silicon membrane pressure sensors for specific applications (automobile, aeronautic, medical)
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Pressure range
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Temperature range
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Sensitivity / accuracy
Transduction Probre integration Packaging
Design Technology
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Multisensors integration
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Integration of communication circuits / wireless sensor
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Development of new transduction type
Developments achieved : 1980
2005
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Capacitive transduction : silicon / pyrex
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Piezoresistive transduction : mono and polycristalline silicon gauges
CAPACITIVE SENSORS
• 20
m
m < H < H1 • 300 • 1.5
m m
m < H1 < 500 m < D < 3
m
m • 2 mm < L < 4 mm
m
• Chip area : 5 x 5 mm m • 0.5 mm < H2 < 1.5 mm 2 to 7 x 7 mm 2 Functional characteristics
• Pressure range : • Nominal capacitance : • Full scale response (FS) : • Nonlinearity : • TCO : • TCS : • Temperature range : 0.1 to 100 bars 10 to 100 pF 5 to 15 % ± 1 to ± 3 % FS < 100 ppm / °C 100 to 2000 ppm / °C - 40 to 180 °C
Pressure sensor for automobile tire : 0 / 6 bars, - 40 / 120 °C
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CAPACITIVE SENSORS –
Two linear range
110 100 90 80 70 60 50 40 30 20 0 2 4 6 8 10 12 Pressure (bar) 14 16 18
Mohamad Al Bahri (Oct 2000 / May 2005) Fouad Kerrour May 2006 / Oct 2007 PhD Univ. Constantine
23,6 23,4 23,2 23,0 22,8 22,6 22,4 22,2 22,0 21,8 21,6 Sp = 2 pF/bar NL = ± 1.2% FS 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 Pressure (bar) 45 44 43 42 41 40 39 38 37 36 Sp = 2.3 pF/bar NL = ± 1.7% FS 4,0 4,5 5,0 5,5 6,0 6,5 Pressure (bar) 7,0 7,5
220 210 200 190 180 170 G g 160 150 140 130 120 110 100 90 80 -30 7 0
CAPACITIVE SENSORS -
Offset : α (Pyrex-Alu)
Thermal drift in circular cavity
Sensitivity : α (Pyrex-Si)
Mohamad Al Bahri (Oct 2000 / May 2005)
F f 6 E e 5 Electrode thickness = 0,8 µm (Al) B A d c b a 4 3 30 60 90 Température (°C) 2 120 1 Electrode thickness = 0,1µm (Al) 150 600 400 200 q v00 0 -200 -400 -600 -800 -1000 -1200 -1400 -1600 -1800 -2000 -2200 -2400 -2600 -20 0 20 40 60 80 h 100 T v 120 140 160
Fouad Kerrour May 2006 / Oct 2007 PhD Univ. Constantine
1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 -100 Resonant frequency : α (Pyrex-Si) G 7 g q f 00 F 6 f E 5 e D 4 d C 3 c h B 2 b T f -20 0 20 40 60 80 100 Température (°C) 120 140 160 300 200 100 0 -100 -200 -300 -400 -500 -600 -700 -800 -900 -1000 -1100 -1200 TC[Sp] -30 0
fr
=2TC[Co] -2TC[fr] TC[Sp] 30
Sv
=TC[Sv] -2TC[Co] 60 90 Temperature (°C) 120 150 Top view Bottom view 5
Silicon Stress gauges L
PIEZORESISTIVE SENSORS
Wheatstone bridge R 2 R 1 H V s V a R 3 R 4
10
m
m < H < qq 100 Chip area : 1 mm 2
m
m qq 100 µm < L < qq mm to several 10 mm 2
V s V a
1 4
R
2
R
2
R
4
R
4
R
1
R
1
R
3
R
3
Functionnal characteristics
- Pressure range : - Bridge resistance : - Full scale response (FS) : - Nonlinearity : - Nominal Offset : - TCO : - TCS : - Temperature range : 0.1 to 100 bars 1 to 3 k 0.5 to 3 % Va < ± 1 % FS < 1 % Va 5 to 100 ppm / °C 1000 to 2500 ppm / °C - 40 to 125 °C (400°C) 6
PIEZORESISTIVE SENSORS
High temperature sensor for aeronautic application
- SOI wafer - Temperature range : - Pressure range : - Offset : - Sensitivity : - 40 à 400 °C 0.1 à 10 bars 0.1 % de la tension d’alimentation 2 mV/V/bar - TCS : 1200 ppm / °C
2001 : Industrial transfer (Auxitrol)
Miniature sensor for medical application (intracranial)
- Temperature range : 20 à 45 °C - Pressure range : - Offset : - Sensitivity : - TCO : - 80 à 400 mbars 0.1 % de la tension d’alimentation 5 µV/V/mbar 0.2 mbar / °C
Validation phase (HEMODIA)
Mohamad Al Bahri Post doc (Dec 2005 – Dec 2006)
1.5 mm 7
EFFECT OF GAUGE LENGHT (L) AND POSITION ON PIEZORESISTIVE SENSOR SENSITIVITY
Membrane position 150 -6 L = 100 160 -4 L = 60 L = 80 170 -2 180 0,00E+00 0 -1,00E-01 -2,00E-01 -3,00E-01 -4,00E-01 -5,00E-01 -6,00E-01 -7,00E-01 -8,00E-01 -9,00E-01 R/R (%) 190 2 L = 40 200 4 L = 2 210 6 Jauge ref erence jauge L=40" jauge L=60" jauge L=80" jauge L=100"
Silicon die
EFFECT OF NON IDEAL CLAMPED MEMBRANE ON PIEZORESISTIVE SENSOR
y Silicon membrane x Rotation at anchorage
Clamped die
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x -
y
MPa 20 Clamped membrane 15 Clamped die 10 5 0 0 -5 50 100 150
X axis (µm)
200 250
Clamped membrane
EFFECT OF NON IDEAL CLAMPED SILICON DIE ON PIEZORESISTIVE SENSOR
Silicon die Silicone joint 500 µm Sensor deformation under pressure
Silicone joint deformation No significant effects on sensor sensitivity
MINIATURE TELEMETRIC PIEZORESISTIVE PESSURE
SENSOR WITH IN SITU SELF-CALIBRATION
Framework
- ANR project (Dec 06 / Dec 09) Partners : HEMODIA, INSERM, Toulouse Hospital, Epsilon - Regional project (submitted) - Joint Laboratory with HEMODIA (submitted)
Applications :
Intracranial and Intravascular pressure sensor
Objectives
- Sensor miniaturization : local measurement, reduce probe traumatism Die width < 500µm
Michal Olszacki
Membrane thickness 1µm (SOI)
Oct 2005 / Nov 2008
Implanted gauge thickness 0.1µm, Gauge width < 1µm
PhD Lodtz Univ. grant
- In situ-autocalibration : eliminate external calibration (reduce infection risks) SOI / Pyrex technology
Cesary Maj Oct 2005 / Nov 2008
Integration of electrostatic pressure generator
PhD Lodtz Univ grant.
Integration of high stability voltage source (INSERM) - Sensor integration into the probe (stress assembly, bio-compatibility)
Mohamad Al Bahri Dec 2006 / Dec 2009 Post doc ANR Pierre Yameogo Janv 2007 / Dec 2009) PhD CIFRE HEMODIA
- Telemetric output (INSERM) : eliminate external cable
WIRELESS PASSIVE PRESSURE SENSOR
RF transduction : resonance frequency modification of planar resonator
Mehdi Jatlaoui Oct 2005 / Dec 2008 PhD Tunisia grant MINC collaboration (Hervé Aubert)
P
Example of 30GHz resonator
Others frequency possible (resonator design)
Frequency
: Size
Very high sensitivity to pressure
Aerospace Valley project (submitted) : Sept 07 / Sept 10
COLLECTIVE PACKAGING FOR PRESSURE SENSOR
Framework : Auxitrol collaboration (Oct 06 / Oct 09)
Jean François Le Néal Nov 2006 / Oct 2009 PhD CIFRE AUXITROL
Objectives :
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Oil suppression (increase temperature range, reduce drift)
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Collective process : reduce costs
Studies
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Cap assembly
Pyrex, silicon
Anodic bonding, thermocompression, eutectic bonding
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Surface micromaching
Polymer sacrificial layers
Thick dielectric cap layers
SUPERCRITICAL CO2 FOR MEMS APPLICATION
Framework : - Regional project (Oct 06 / Oct 08) - RECIF collaboration - Joint Laboratory with RECIF ?
Laurent Rabbia – Vincent Perrut RECIF Engineer ??????
Oct 2007 / Sept 2010 PhD CIFRE RECIF ?
Objectives : Use of supercritical CO2 properties (low interfacial tension)
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Wet etching of polymer sacrificial layer and C02 drying in the same chamber
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Complete micromachining under supercritical state Surface conditionning with Self Assembled Monolayer into CO2
Applications
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MEMS release
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Packaging release Microfluidics
POSSIBLE NEW PROJECTS
I ntegration of pressure sensors with chemical sensors (FET gauge)
Stress sensors for buried pipes (Veolia)
Stress sensors for satellite (Astrium / Regional project submitted)
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Wireless stress network
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MINC collaboration
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