un terme générique pour désigner les microsystèmes réalisés avec les technologies de microusinage

1. UE#MEMS#
#
Cours#1#:#bases#théorique#des#systèmes#
électromécaniques#intégrés#
Dimitri&Galayko&(dimitri.galayko@lip6.fr)&
Tél.&01&44&27&70&16,&salle&403c&tour&65D66&
#
1#
Plan#du#cours#1#
• MEMS#:#introduc>on#et#programme#de#l UE#
• Introduc>on#à#la#physique#de#systèmes#
électromécaniques#:#rappel#des#éléments#de#la#
mécanique#(au#tableau#+#fiches#de#rappel)#
• Interfaces#électromécaniques#à#l aide#de#
transducteurs#électrosta>ques#
– Introduc>on#:#discussion#sur#les#transducteurs#
– Géométries#de#transducteurs#électrosta>que#
– Conversion#mécaniqueIélectrique#
– Conversion#électriqueImécanique##
• Bibliographie#:#S.#Senturia,#Microsystem#Design##
2#
Informa>on#générale#sur#l UE#
Equipe#pédagogique#:#Dimitri#Galayko,#Philippe#Basset#(ESYCOM)#
• Cours#1#:#Bases#théoriques#des#MEMS#:#Rappel#de#la#mécanique#:#systèmes#
mécaniques#à#paramètres#localisés,#équivalence#électromécanique,##
transducteur#capaci>f,#modélisa>on#(TP1.1)#
• Cours#2#:#Structures#mécaniques#des#MEMS#:#poutres,#résonateurs,#
éléments#de#la#mécanique#du#solide.#Transduc>on#piezoélectrique#et#sa#
modélisa>on#(TP1.2).##
• Cours#3#:#Technologies#de#microIusinage#de#silicium#(intervenant#externe#P.#
Basset,#ESYCOM)##
• Cours#4#:#Applica>ons#des#MEMS#:#capteurs,#MEMS#RF,#récupéra>on#
d énergie,#intégra>on#avec#l électronique#
• TP2I3:#miniIprojet#:#concep>on#et#modélisa>on#d un#accéléromètre#
asservi,#ou#d un#oscillateur#à#base#de#résonateur#MEMS#(Dimitri#Galayko)#
#(1#cours#ou#TP#correspond#à#un#créneau#de#4#heures)##
3#
MEMS:#introduc>on#
• MEMS:#un#terme#générique#pour#désigner#les#microsystèmes#
réalisés#avec#les#technologies#de#microusinage##
• Le#plus#souvent#il#y#a#une#par>e#mécanique,#mais#pas#toujours#
(exemple#:#une#inductance#3D#microIusinée)#
• La#significa>on#de#l’abrévia>on#MEMS#:##
– «#Micro#»#:#technologies#de#microusinage#issues#de#la#
microélectronique#classique#
– «#Electro*mechanical#»#:#il#y#a#du#traitement#du#signal#effectué#dans#le#
domaine#mécanique#et#électrique#
– «#System#»#:#ce#terme#souligne#la#complexité#du#disposi>f,#sa#
fonc>onnalisa>on#forte#
• Echelle#:#1I3000#μm#–#MEMS,#<1μm#–#NEMS##
• Important#:#usinage#de#surface#–#usinage#de#substrat,#
technologies#de#silicium#!##
4#

2. MEMS:#introduc>on#
• Un#peu#d histoire#:#
– Richard#Feynman#(Prix#Nobel#Physique),#«#There s#
Plenty#of#Room#at#the#Bofom#»,#présenta>on,#le#
26#décembre#1959#à#CalTech#
hfp://www.zyvex.com/nanotech/feynman.html#
– Wes>nghouse#a#crée#un#transisotr#MOS#avec#une#
grille#résonnante#
– Capteurs#de#pression#à#par>r#du#silicium#usiné#en#
volume:#1970##
– Transducteur#électrosta>ques#à#peignes#
interdigités#:#1980#
5#
MEMS:#introduc>on#
Élément#mobile#(résonateur,#interrupteur)#
Membrane#(capteurs#de#pression…)#
Microusinage#de#volume##
(bulk#micromachining)#
Microusinage#de#surface##
(surface#micromachining)#
Technologies&MEMS&
6#
MicroIusinage#:#principe#
(plus#de#détails,#cf.#cours#3)#
• ##Microusinage#
de#surface#
U. Srinivasan ©
EEC245
MEMS Processing
• Unique to MEMS fabrication
• Sacrificial etching
• Mechanical properties critical
• Thicker films and deep etching
• Etching into substrate
• Double-sided lithography
• 3-D assembly
• Wafer-bonding
• Molding
• Integration with electronics, fluidics
• Unique to MEMS packaging and testing
• Delicate mechanical structures
• Packaging: before or after dicing?
• Sealing in gas environments
• Interconnect - electrical, mechanical, fluidic
• Testing – electrical, mechanical, fluidic
Package
Dice
Release
sacrificial layer
structural layer
Photolithography:
Masks and Photoresist
• Photolithography steps
• Photoresist spinnning, 1-10 µm spin coating
• Optical exposure through a photomask
• Developing to dissolve exposed resist
• Bake to drive off solvents
• Remove using solvents (acetone) or O2 plasma
10
U. Srinivasan ©
EEC245
• Distribution of exposed area ~ loading
• Structure geometry
U. Srinivasan ©
EEC245
Anisotropic Etching of Silicon
• Etching of Si with KOH
Si + 2OH- Si(OH)2
2+ + 4e-
4H2O + 4e- 4(OH) - + 2H2
<100>
Maluf
• Crystal orientation relative etch
rates
• {110}:{100}:{111} = 600:400:1
• {111} plane has three of its bonds
below the surface
• {111} may form protective oxide
quickly
• {111} smoother than other crystal
planes
• ##Microusinage#
de#volume#
7#
MEMS#:#interface#entre#2#mondes#
• La#clé#du#succès#des#MEMS#:#une#possibilité#de#
rapprocher#l électronique#de#la#mécanique#
• L élément#clé#:#un#transducteur#électromécanique#
• Un#transducteur#:#un#système#qui#couple#un#signal#
électrique#à#un#signal#mécanique#
• Deux#types#principaux#:#électrosta>que#et#
piézoélectrique#
8#

3. MEMS:#introduc>on#
Peut#être#u>lisé#:##
• dans#les#applica>ons#
op>ques#(contrôle#très#
précis#de#la#posi>on),##
• dans#les#disposi>fs#de#
conversion#d’énergie##
Illustre#bien#les#possibilités#
de#la#technologie#MEMS#
Moteur#électrosta>que#
9#
MEMS#:#introduc>on#
Transistor#à#grille#résonnante#
10#
MEMS:#introduc>on#
• Raisons#du#succès#:##
– Technologie#issues#de#la#microélectronique:#avantages#de#la#
produc>on#à#grande#échelle#(fabrica>on#dite#collec>ve,#ou#batch*
processing)#
– Exten>on#de#la#base#de#composants#de#la#microélectronique#
classique#:#capacité#variable,#interrupteur#mécanique,#résonateur#à#
très#haut#Q,#microImiroirs,#etc.#
– Possibilités#infinie#de#réaliser#des#capteurs/ac>onneurs#qui,#de#plus,#
sont#intégrés#sur#la#puce,#donc#à#proximité#de#l’électronique#de#
traitement#
– Miniaturisa>on#de#systèmes#mul>physique#:#économie#substan>elle#
de#la#place,#de#la#consomma>on#d’énergie,#des#parasites.##
11#
MEMS:#introduc>on#
• Raisons#du#succès#N°1:#la#fabrica>on#collec>ve#
(batch#process)#:#
12#

4. MEMS:#introduc>on#
• Raisons#du#succès#N°2:#la#réduc>on#de#l échelle#modifie#le#«#rapport#
des#forces#»#existant#dans#le#macromonde.##
• Notamment,#les#forces#d origine#électrique#(électrosta>que)#
deviennent#comparables#avec#les#forces#mécaniques#(élas>ques)#
• #Les#forces#de#gravité##
#sont#négligeables#
• #La#contrepar>e#:#les#forces##
#de#surface#deviennent#
#nonInégligeables#
13#
MEMS:#introduc>on#
• Raisons#du#succès#N°3:#U>lisa>on#très#large#de#structures#résonnantes##
• Résonateur#LC#intégré:#très#mauvais#performances#(Q~10#en#HF#uniquement)#
• Résonateur#LC#basse#fréquence#:#impossible#d’intégrer#
• Résonateur#MEMS#:#basse#fréquence#(à#part.#des#1I10#Hz),#très#
grand#Q#(jusqu’à#105)##
Applica>ons#innombrables#!#
Yang#et#al.,#Sensors#actuators#
#journal:#A,#2000###
14#
Les#principales#familles#des#disposi>fs#
MEMS##
• Capteurs#iner>els##
• Capteurs#résonants#et#membranes##
• Disposi>fs#RF#passifs#(MEMS#RF)#
• Microfluidique##
• Disposi>fs#op>ques#
15#
Les#marchés#par#faimilles#de#
composants#
MEMS Market Breakdown 2011/2017
InkJet Heads
15%
Pressure
Sensors
14%
Microphones
4%
Accelerometers
15%
Gyroscopes
13%
Compasses
4%
Combos
1%
Uncooled IR
3%
Micro displays
0%
Optical MEMS
11%
Microfluidics
14%
RF MEMS
4%
Oscillators
0%
Others
(microstructure
s, micro tips,
flow meter …)
2%
InkJet
Heads
9%
Pressure Sensors
11%
Microphones
4%
Accelerometers
8%
Gyroscopes
7%
Compasses
2%
Combos
8%
Uncooled IR
3%
Micro displays
1%
Optical
MEMS
12%
Microfluidics
23%
RF MEMS
5%
Oscillators
2%
Others
(microstructures,
micro tips, flow
meter …)
5%
2017 MEMS Market Value
Breakdown
(TOTAL $21B)
2011 MEMS Market Value
Breakdown
(TOTAL $10,2B)
Yole#Développment,#
#2012#
#
hfp://dmems.univI
fcomte.fr/presenta>ons/
mounier.pdf#
16#

5. Capteurs#iner>els#
• Capteurs#iner>els#:#accéléromètres,#gyroscopes#
(commercialisé#par#Analog#Devices,#Motorola#depuis#
1991)#
• Applica>ons#:#au#départ#automobiles#(airbag),#
avia>on,#maintenant#iPhones,#Wii,&applicaJon&
militaires&…##
• Actuellement#les#acteurs#clés#:#Bosch#Group,#ST#
Microelectronics,#Kionix,#Freescale#Semiconductors##
• Le#marche#global#$1.55B#en#2009#
#
17#
Capteurs#iner>els#
Structure#d un#capteur#d accéléra>on#u>lisé#pour#airbag#
18#
Capteurs#iner>els#
Accéléromètre#complet#:#capteur#intégré#avec#ces#circuits#
de#condi>onnement##
19#
Capteurs#résonants#
• A#la#base,#un#microIrésonateur#(poutre#
encastréeIencastrée,#encastréeIlibre…)#associé#
à#un#transducteur#
• La#fréquence#d’oscilla>on#est#impactée#par#
diverses#facteurs#exogènes#(température,#
environnement#gazeux,#etc…)#
• Capteurs#d’énergie#ciné>que##
• Applica>ons#RF##
20#

6. Capteurs#résonants##
• Raison#du#succès#:#de#très#bonnes#qualités#mécaniques#du#
silicium#
– Fables#pertes#mécanique#(grand#facteur#de#qualité)#
– Elas>cité#&#solidité#(grandes#amplitudes)#
– Facilité#d’associer#avec#des#transducteurs#électromécaniques:#
capaci>f,#piézoélectrique#
Résonateur#avec#transducteur#
à##peignes#interdigitées,#MNX#
#
Fréquence#:#~10I100#kHz#
Q:# #jusqu’à#100#000#dans#le#vide#
21#
Capteurs#résonants#
• Applica>ons#:##
– Mesure#de#température#
– Mesure#de#la#masse#(compteurs,#détecteurs##de#gaz)#
– Microscopie#à#force#atomique#
– Mesure#de#pression##
• Raison#du#succès#:##
– On#crée#un#oscillateur#oscillant#à#la#fréquence#propre#du#
résonateur,#et#on#mesure#la#fréquence#
– La#fréquence#:#très#facile#à#mesurer#
22#
Capteurs#résonants#
Premier#disposi>f#MEMS#
intégré#avec#les#circuits##
#
Capteur#de#vapeur#résonant,#à#base#
de#microIpont#
23#
Capteurs#résonants#
Accélérometre#MEMS#3#axes##
24#

7. Capteurs#résonants#
Accéléromètre#complet#:#capteur#intégré#avec#ces#circuits#
de#condi>onnement##
25#
MEMS#RF#
• #RF#MEMS#:#concept#
promefeur#au#début#
des#2000#
• Radio#réconfigurable/
mul>standard#
26#
MEMS#RF#
• Applica>ons#100MHz#I#40GHz#
• L ac>onnement#DC#peutIêtre#compris#dans#le#signal#ou#appliqué#
à#l aide#d une#électrode#séparée#
gnd&
gnd&
signal&
Interrupteur&bloqué&
gnd&
gnd&
signal&
Interrupteur&passant&
Interrupteur#RF#
27#
MEMS#RF#
Interrupteur#ohmique# Interrupteur#capaci>f#
28#

8. MEMS#RF#
Capacité#contrôlée#par#une#tension#:##
(pour#la#varia>on#de#la#fréquence#d’élément#LC)#
29#
MEMS#RF#
Une#autre#capacité#contrôlée#par#une#tension:##
30#
MEMS#RF#
Filtre#électromécanique#pour#les##
fréquences#intermédiaires#(Clark#T.C.#Nguyen)#
31#
Microfluidique#
• Manipula>on#de#liquide#à#très#pe>tes#
quan>tés#:#des#microlitres,#dans#des#canaux#de#
largeurs#micrométriques#
• Une#branche#de#science#de#l’ingénieur#et#
technologique#rela>vement#nouvelle##
• Applica>ons:#biologie,#analyse#chimique#de#
gaz/liquide##
• 14#%#du#marché#MEMS##
32#

9. Microfluidique#
• Manipula>on#de#liquides#et#de#par>cules#par#
champ#électrique#:#micropompes,#mélangeurs#
• Manipula>on#de#cellules##
• Manipula>on#de#cellules#
• Séquenceurs#d’ADN#(Puces#à#ADN)#
me of normal saline
mally extracted ISF
o establish electrical
le it is transferred
me of normal saline
E3, shown as the red
e extraction chamber
ctrode pair E3 and
ves. And the volume
blue curve in Figure
)
43 tt
S
−
+ , (1)
crochannel between
the width and height
time for the head of
e pair E1 and E2, t3
ple flowing through
0mm) is the distance
. The volume of
to the difference
efined input volume
ensor for controlling
asy collection of ISF
Collection Chamber,
Saline Chamber, D:
Saline. V1-V3 are
rs of electrodes.
lucose Sensor
concentrations of the
S dielectric glucose
ated electrode and a
acitive detector, is
tem. As shown in
s situated inside a
se-sensitive polymer
a semi-permeable
tween glucose and
) causes permittivity
solution, which is
r to determine the
ISF Transdermal
cose Sensor
top layer of the ISF
volume sensor for
n. A microchamber
(Figure 5) is aligned between the extraction chip and the
glucose sensor for containing the collected ISF sample in
glucose concentration measurement step.
Figure 3: Schematic of the dielectric glucose sensor.
Figure 4: The polymer composition and the mechanism of
interaction with glucose.
Figure 5: Schematic of the integration structure between
ISF transdermal extraction chip with volume sensor
(TECVS) and MEMS dielectric glucose sensor. APGS:
Access Ports for Glucose Sensor.
FABRICATION PROCESS
The microfluidic chip without glucose sensor, which
is designed for ISF transdermal extraction, collection, and
volume measurement, is fabricated from five PDMS layers
using micromolding techniques. 250 m thick epoxy dry
films (SUEX TDFS, DJ DevCorp) and photoresist films
(FX930, DuPont) instead of common photoresists are
utilized for micromolds fabrication. As shown in Figure 6a,
the electrodes of the volume sensor are fabricated with
conductive PDMS (Ag- P/PDMS, 11:2 weight ratio)
similar to the method utilized by Niu et al. [6]. After
molding, the five PDMS layers are aligned and bonded
together using Corona (Laboratory Corona Treater,
BD-20ACV, Electro-Technic Products, Inc.).
For the fabrication of the MEMS dielectric glucose
sensor (Figure 6b), two gold layers are firstly deposited,
patterned, and passivated with Parylene to form the bottom
electrode and perforated electrode. And a sacrificial
photoresist layer is deposited and patterned between the
two gold layers. Then two SU-8 layers are deposited and
patterned to form the diaphragm and the sensor chamber.
366
Mesure#de#glycémie#sur#puce#
Transducer#2013,#Li#et#al.#
#
33#
Microfluidique#
34#
Microfluidique#
• Domaine#scien>fique#rela>vement#nouveau#:##
– Comportement#de#liquides#à#volumes#réduits#
– Interac>on#avec#le#champ#électrique#
– Technologies#(biocompa>bles#?)##
• Domaine#en#plein#essor##
35#
MEMS#pour#op>que:#MOEMS#
• Domaine#:#traitement#d’informa>on#
op>que,#principalement#dans#les#télécoms#
• #Interrupteurs,#miroirs##
Interrupteur#op>que##
Sélec>onneur/mul>plexeur#
op>que#à#microImiroirs# 36#

10. MEMS#pour#op>que:#MOEMS#
• Membranes#déformables#pour#l’op>que#
adapta>ve:#len>lles#&#miroirs#contrôlées#
Introduction
In this paper we present a single-crystal-silicon continuous
membrane deformable mirror array with electrostatic actuation for
applications in adaptive optics [1, 2]. Adaptive optics used to
correct for atmospheric distortion requires large strokes of up to
several microns. In space-based telescopes, where atmospheric
distortion is a non-issue, imperfection of the optical system is the
main reason for image degradation. Under these conditions, short-
stroke programmable adaptive optics can correct for imperfections
in the optical elements, such as local defects of a few nanometers to
large curvature flaws of several hundred nanometers, and for mis-
alignments without the prohibitively high cost of having to replace
the components. In such systems continuous face-sheet mirrors, as
described in this paper, are more suitable than segmented mirrors
since these types of mirrors add to the degradation by lower fill-
factor and diffraction.
Figure 1. (a) Cross-section diagram of a single deformable mirror
pixel. (b) Cross-section diagram of an array
Design and Fabrication
Our approach to the fabrication of continuous membrane MEMS
mirrors differ from earlier reported methods [3,4,5,6] in that we
fabricate the electronics and MEMS on different wafers and
combine these with flip-chip bonding [7]. The advantage of this
approach is that the MEMS and electronics can be optimized
independently and separate foundries can be used for each. In
particular, the electronics can be made in a standard foundry
without the extra complexity that is associated with direct
the fabrication of the top membrane using a sufficiently flat low-
stress SCS device layer.
Figure 2. SEM of a pixel with the membrane partially removed to
show the underlying structure
The diagrams in Fig. 1 show the structure of the deformable mirror.
Figure 1(a) shows the cross-sectional view of a single pixel and Fig.
1(b) shows three elements of an array. Figure 2 shows a SEM of
the structure. The upper electrode, membrane and spring structures
are all at the ground potential and the bottom electrodes are
individually addressed for control of the array. A potential applied
between the two electrodes pulls the membrane towards the
substrate by parallel-plate actuation.
The fabrication for the MEMS and electronics wafers is done
separately and flip-chip bonded together (Fig 3.). The top
membrane is a 300nm SOI (silicon-on-insulator) device layer. The
pedestal that links the membrane and upper electrode plate is
formed by a 2.0 m poly via that also forms the upper electrode and
mechanical spring layer. As shown in Fig. 1(b), the mechanical
springs are attached to the frame of the actuator and to the upper
electrode. The upper and lower electrode areas are both 50 m x
50 m. The 3.0 m gap between the upper and lower parallel plate
electrodes is determined by the 2.0 m thick poly layer offsets made
on the electronics chip and gold bond layers of 0.5 m. Wiring lines
and lower electrodes are formed on the lower poly layer. The
1520-7803-9562-X/06/$20.00 ©2006 IEEE
for Adaptive Optics
Il Woong Junga
, Yves-Alain Peterb
, Emily Carrc
, Jen-Shiang Wanga
and Olav Solgaarda
a
E. L. Ginzton Laboratory, Department of Electrical Engineering, Stanford University, Stanford, CA 94305
Tel +1-650-723-1992, Fax +1-650-725-2533, E-mail: iwjung@stanford.edu
b
Départment de Génie Physique, Ecole Polytechnique de Montréal, Montréal, Québec Canada
c
Lawrence Livermore National Laboratory
Abstract
e present a single-crystal-silicon (SCS) continuous membrane deformable mirror array with applications as a corrective adaptive optics
ement for space-based telescopes. The continuous membrane is made from a thin silicon-on-insulator (SOI) layer with good optical surface
uality. The membrane is able to deform locally by 125nm at 100V with a resonance frequency of 25kHz.
Introduction
this paper we present a single-crystal-silicon continuous
embrane deformable mirror array with electrostatic actuation for
plications in adaptive optics [1, 2]. Adaptive optics used to
rrect for atmospheric distortion requires large strokes of up to
veral microns. In space-based telescopes, where atmospheric
stortion is a non-issue, imperfection of the optical system is the
ain reason for image degradation. Under these conditions, short-
roke programmable adaptive optics can correct for imperfections
the optical elements, such as local defects of a few nanometers to
rge curvature flaws of several hundred nanometers, and for mis-
ignments without the prohibitively high cost of having to replace
e components. In such systems continuous face-sheet mirrors, as
scribed in this paper, are more suitable than segmented mirrors
nce these types of mirrors add to the degradation by lower fill-
ctor and diffraction.
gure 1. (a) Cross-section diagram of a single deformable mirror
xel. (b) Cross-section diagram of an array
Design and Fabrication
ur approach to the fabrication of continuous membrane MEMS
irrors differ from earlier reported methods [3,4,5,6] in that we
bricate the electronics and MEMS on different wafers and
mbine these with flip-chip bonding [7]. The advantage of this
proach is that the MEMS and electronics can be optimized
dependently and separate foundries can be used for each. In
rticular, the electronics can be made in a standard foundry
ithout the extra complexity that is associated with direct
integration of MEMS. Just as important, this method also allows
the fabrication of the top membrane using a sufficiently flat low-
stress SCS device layer.
Figure 2. SEM of a pixel with the membrane partially removed to
show the underlying structure
The diagrams in Fig. 1 show the structure of the deformable mirror.
Figure 1(a) shows the cross-sectional view of a single pixel and Fig.
1(b) shows three elements of an array. Figure 2 shows a SEM of
the structure. The upper electrode, membrane and spring structures
are all at the ground potential and the bottom electrodes are
individually addressed for control of the array. A potential applied
between the two electrodes pulls the membrane towards the
substrate by parallel-plate actuation.
The fabrication for the MEMS and electronics wafers is done
separately and flip-chip bonded together (Fig 3.). The top
membrane is a 300nm SOI (silicon-on-insulator) device layer. The
pedestal that links the membrane and upper electrode plate is
formed by a 2.0 m poly via that also forms the upper electrode and
mechanical spring layer. As shown in Fig. 1(b), the mechanical
springs are attached to the frame of the actuator and to the upper
electrode. The upper and lower electrode areas are both 50 m x
50 m. The 3.0 m gap between the upper and lower parallel plate
electrodes is determined by the 2.0 m thick poly layer offsets made
on the electronics chip and gold bond layers of 0.5 m. Wiring lines
and lower electrodes are formed on the lower poly layer. The
1523-9562-X/06/$20.00 ©2006 IEEE
Jung,#I.#et#al.,#SingleICrystalISilicon#Con>nuous#Membrane#Deformable#Mirror#Array#for#Adap>ve#Op>cs.#In#
Op>cal#MEMS#and#Their#Applica>ons#Conference,#2006.#
37#
MEMS:#introduc>on#
• Automobile#:#système#N°1#qui#peut#profiter#
des#MEMS#
• #Contrôle#de#déploiement#
# ##de#airbag#
• #Contrôle#de#la#dynamique#
#du#véhicule#
• #Système#de#naviga>on…##
38#
MEMS:#introduc>on#
• Téléphonie#mobile#:#applica>on#phare#
© 2012• 9
2011 Copyrights © Yole Développement SA. All right reserved.
… to Smartphones: where the business is today.
Microphone
BAW filters/duplexers
RF switch / variable capacitor
Oscillator
Micro mirror
Auto focus
Accelerometer
Gyroscope
Electronic compass
Pressure sensor
Micro display
Proximity sensor
39#
MEMS:#introduc>on#
Ressources#en#ligne#:##
40#