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Skills: the silicon- and polymers-based microtechnologies

Technological processes Materials integration and study

Groupe M2D"Microdevices et microsystems of detection"

Head director: P. Temple-Boyer

Senior researchers (11) E. Bedel-Pereira (CR) F. Cristiano (CR) L. Fadel Taris (MC) J. Launay (MC associé) A. Martinez (P) P. Ménini (MC) F. Olivié (P) P. Pons (CR) G. Sarrabayrouse (DR) E. Scheid (CR) P. Temple-Boyer (CR-HDR)

Post-docs (3) M. Al Bahri (post-doc) I. Humenyuk (post-doc) M.L. Pourciel-Gouzy (post-doc)

Ph-D students (21)

Others (3)

F. Kerrour (Constantine, ALGERIA) L. Rabbia (RECIFE) W. Sant (CAPTOMED/HEMODIA)

Microstructures and microdevices Microsystems of detection

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Objectives and motivations

Development of microdevicesusing silicon and polymers technologies,Application to detection microsystems…

Integration Technological processes and materials: structure, detection, actuation, packaging,… Microstructures, microdevices, microsystems Electronic interfaces: measurement, data treatment, communication,…

Development of technological platforms Compatibility of the microelectronics technology Mass fabrication at low cost

Adaptation according to application Improvement, optimisation, reliability Industrial transfer

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Micro/NanoelectronicsMicro/Nanotechnologies

MICRODEVICES

Researches organisation

Technological building blocks

BASIC RESEARCHIN SILICON & POLYMERS

TECHNOLOGIES

Materials, processes

Microdevices platforms

MECHANICS, PHYSICS, (BIO)CHEMISTRY, BIOLOGY

MICROSYSTEMSOF DETECTION

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Study of detection microsystems

Conception and realisation of demonstrators Microdevices, microtransducers Microsystems of detection, microsensors

Characterisation, instrumentation Development of specific measurement stands Study of transduction principles

• Potentiometric transduction• Impedimetric transduction• Electro-mechanical transduction

Conception and realisation of specific interfaces Development of data treatment methods

Theory, modelling, simulation Understanding of the detection microsystems behaviour Optimisation, reliability

Industrial transfer

MOS dosimeter

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Development of detection microsystems

MOS dosimeters (RadFETs) Ionizing radiations dosimetry Neutrons dosimetry

Pressure/stress MEMS-based microsensors Capacitive transducers Piezoresistive transducers

MEMS-based conductimetric gas sensors

Chemical microsensors Chemical field effect transistors (ChemFETs) Chemical microelectrodes

Staff: 11 people- Senior researchers: 3 - Post-docts: 2 - Engineers/Technicians: 3 - PhD student: 2- Private engineer: 1

1,5mm

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Integration of ChemFET microsensors

Adaptation of the MOSFET to the detection in liquid phase

Substitution of the metallic gate by a chemical sensitive layer

Use of a electrolyte/insulator/silicon (EIS) gate structure

Detection principle Charges (ions…) trapping on the chemical sensitive layer, variation of the electrolyte

potential 0 (Nernst law) and measurement of the ChemFET threshold voltage VT*

Advantages and drawbacks+ Compatibility with microelectronics (theory, technology, measurement interfaces,…)- Requirement of an optimised packaging adapted to the detection in liquid phase- Use of a (pseudo-)reference electrode to apply the Gate voltage bias to the electrolyte

electrolyte

Gate

P type silicon substrate

Source Drain

0+

Source Drain

P type silicon substrate

SiO2

Si3N4

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Integration of pH-metry techniquesfor biochemical analysis

Development of a SiO2/Si3N4 pH-ChemFET technological platform

Design and realisation using silicon and polymers technologies

Assembly, packaging and conditioning to the liquid phase

Test and characterisation Simulation and modelling

pH-ISFET/-ReMOSmicrosensor

1cm

0 10 20 30 40 50 60 70-1,65

-1,60

-1,55

-1,50

-1,45

-1,40

-1,35

-1,30

-1,25

pH

ten

sio

n d

e s

ort

ie (

V)

temps (min)

3

4

5

6

7

8

9

10pH glass electrode

pH microsensor

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Detection of bacterial activities

Monitoring of the bacterial medium pH using pH-ChemFETs Fabrication of mass-fabricated PDMS microtanks (≈ 1 mm3) Integration on the pH-ChemFET chip, connexion (electrical and fluidic) and packaging Introduction to fluidic microsystems…

Study of the non pathogenic bacteria lactobacillus acidophilus Main bacterial metabolism: consumption of specific sugars, fabrication of lactic acid and

final decrease of the pH bacterial medium Test of sugars characterised by different metabolisms: glucose (+) and sorbitol (-)

0 20 40 60 80 100 120 140800 850 900 95 0

0,94

0,95

0,96

0,97

0,98

0,99

1,00

Vg/

Vg0

time (min)

Test sorbitol

Test glucose

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Adaptation of pH-ChemFETs to biochemical detection: development of EnFETs

Use of enzymatic reactions responsible for a pH variation, adaptation to the detection of biochemical species

Hydrolases: hydrolysis of the amine NH2 function and production of ammonia NH3

Example: urease: CO(NH2)2 (urea) + H2O ----> 2NH3 + H2CO3

R&D works Mass integration of photosensitive polyvinyl alcohol (PVA) based enzymatic layers

using spin coating and photolithography techniques Realisation of enzymatic FETs for the detection of urea and creatinin

enzymatic reaction

Source Drain

silicon substrate

H+/OH-SiO2

Si3N4 PVA

PVA /enzyme

EnFET pH-ISFET

SsD SsD

G

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Technological realisations Mass fabrication of generic pH-ISFET chips using silicon technology Development of "smart cards technology for the pH-ISFET chips wiring and packaging Enzymatic layer deposition using ink jet printing technique Fabrication of a specific flow cell adapted to haemodialysis Use of standard electrical connexions Development of specific measurement interfaces

Application to haemodialysis

EnFETs technology industrial transfer (collaboration: HEMODIA S.A. - France)

pseudo-Gate (Au)

Urea-EnFET

pH-ISFET

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EnFETs modelling

Modelling of the EnFETs detection mechanisms

Enzymatic reaction (Michaelis-Menten equation)

Diffusion in the solution of the (bio)chemical species (Fick law)

Hydrodynamic laws Acid/basic chemical reactions pH-ISFET potentiometric response

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Integration of chemical micro-electrodes

Gold/electrolyte/goldconductive structure

Metal/electrolyte/Si3N4/ SiO2/siliconcapacitive structure

Development of a specific technological platform

Design and realisation using silicon and polymers technologies

Assembly, packaging and conditioning to the liquid phase

Test and characterisation Simulation and modelling Amplifying structure for ChemFEC

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Applications to biological detection

Goal: characterisation of the oxidizing stress of red cells

Towards the paludism diagnosis…

Realisation of Ti/Au micro-electrodes on pyrex substrate

Integration of red cells using thiols and polylysine

Characterisation by impedance spectroscopy 0

2000

4000

6000

8000

10000

12000

0 5000 10000 15000 20000 25000 30000 35000

GR parasité

GR sain

couche sensible

blank testparasitized cell

safe cell

QuickTime™ et undécompresseur TIFF (LZW)

sont requis pour visionner cette image.

Gold micro-electrodes on pyrex substrate

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Conclusion and prospects

Development of chemical microsensors for the liquid phase analysis Realisation of a generic detection microdevices (pH-ChemFET, micro-electrodes) using

silicon and polymer technologies Integration of the (bio)chemical sensitive materials Packaging, hybrid integration Adaptation to the chemical, biochemical and biological detection

Applications Medical analysis: pH-ChemFETs for the analysis of bacterial activities Plasma analysis: EnFETs pour biochemical detection Water analysis: ISFETs pour the ion detection

Towards new microsensors concepts Low-cost microsensors (1 - 10 $) Chemical microdevices: smart cards, probes, pipes,… Chemical microsystems Microsensors networks