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Ken-ya Hashimoto Chiba University [email protected] http://www.te.chiba-u.jp/~ken Part 1: What is SAW Device? Introduction to Surface Acoustic Wave (SAW) Devices April 2, 2019

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Page 1: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Ken-ya HashimotoChiba University

[email protected]://www.te.chiba-u.jp/~ken

Part 1: What is SAW Device?

Introduction to Surface Acoustic Wave (SAW) Devices

April 2, 2019

Page 2: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

•SAW Transversal Filter•SAW Unidirectional IDT Filters•SAW Resonator Filters•Duplexers•Oscillators•SAW Wireless Tags and Sensors

Contents

Page 3: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

•SAW Transversal Filter•SAW Unidirectional IDT Filters•SAW Resonator Filters•Duplexers•Oscillators•SAW Wireless Tags and Sensors

Contents

Page 4: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Surface Acoustic Wave

Bulk Acoustic Wave (BAW):•Longitudinal Wave (Primary Wave)

•Transverse Wave (Shear Wave, Secondary Wave)

Surface Acoustic Wave (SAW):

(Rayleigh SAW)Propagation of

Seismological Waves

Page 5: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Surface Acoustic Wave (SAW) Device

Vout

Vin

Piezoelectric substrate

Interdigital Transducers (IDT)

SAW

• Mass Production by Photolithography• Low loss, Miniature & Low price• Operation inVHF-UHF ranges

Line width /4=0.5m (f=2GHz)

Page 6: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Impulse Response

• Independent Control of Amplitude and Phase Responses

SAW Transversal Filters

Page 7: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Impulse Response Frequency Response

t f

t

t

dtjftthfH )2exp()()(

dfjftfHth )2exp()()(

f

f

Page 8: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Piezoelectricity

(a) Equilibrium (b) Extension

p p

(c) CompressionNecessity of Crystalline AsymmetryDepending on Crystal Orientation

Electric Flux (Electric Field) Stress (Strain)

p: Dipole Moment8

Page 9: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Piezoelectricity

(a) Equilibrium (b) Extension

E E

(c) Compression

Stress (Strain) Electric field (Electric Flux)

E: Electric Field

9

Page 10: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Non-Piezoelectric Case

(a) Equilibrium

No Electric Output

(b) Extension (c) Compression

10

Page 11: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Electrostriction

(a) Equilibrium (b) Compressive

E E

(c) Compressive

Stress (Strain) {Electric field (Electric Flux)}2

p: Dipole Moment

Negligible for Weak Electric field11

Page 12: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Why Acoustic Wave Devices?

• Temperature Stability

]1)/[exp(0 kTqVII

cf. For Si, 3000ppm/oC

ppm 10day 1sec. 1

For watch,

Page 13: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Trade-Off Between Temp. Stability & Bandwidth

T drift

(a) Wider Transition Bandwidth

(b) Narrower Transition Bandwidth

T drift

Efficient Use of Frequency Resources Narrow Transition Bandwidth (Or Improve Production Yield)

Page 14: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

-45-40-35-30-25-20-15-10

-505

-0.2 -0.1 0 0.1 0.2 -1

-0.8-0.6-0.4-0.2

00.20.40.60.81

Tran

sfer

func

tion

in d

B

Relative Frequency

Tran

sfer

func

tion

in d

B

Fourier-Transform-Based Design

Ripple due to truncation [Gibb’s Phenomenon]

Page 15: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

t

w(t)t

thd(t)w(t)

hd(t)

Influence of Truncation

dfWHfH dw )()()(

Convolution Relation

Page 16: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Window Functions

t f

t f

Hamming:w(t)=0.54+0.46cos(2t/T)

Blackmann:w(t)=0.42+0.5cos(2t/T) +0.08cos(4t/T)

Blackmann-Harris:w(t)=0.35875+0.48829cos(2t/T)+0.14128cos(4t/T)+0.01168cos(6t/T)

Page 17: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

0

0.2

0.4

0.6

0.8

1

-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1

Wei

ght

Relative Position

HammingBlackmann

Blackmann-Harris

Page 18: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

-120

-100

-80

-60

-40

-20

0

0 2 4 6 8 10

rectangularHammingBlackmann

Blackmann-Harris

Relative frequency

Am

plitu

de in

dB

Frequency Response of Window Functions with same T

Page 19: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

-70-65-60-55-50-45-40-35-30-25-20-15-10-505

-0.2 -0.1 0 0.1 0.2

-0.8-0.6-0.4-0.2

00.20.40.60.81

-1

Tran

sfer

func

tion

in d

B

Relative frequency

Tran

sfer

func

tion

in d

B

Design by Fourier Transform + Design by Fourier Transform + Window Function

Page 20: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

454137 49 53

10 dB/div

Frequency (MHz)43.7541.7539.75 45.7547.75

1 dB/div

50ns/div

Frequency (MHz)

SAW Transversal Filter for CATV

Ref. 15dB

Page 21: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

8070605040302010

0

67.5 68 68.5 69 69.5 70 70.5 71 71.5 72 72.5

Inse

rtion

loss

in d

B

Frequency in MHz

ExperimentSimulation

SAW IF Filter for IS-95

Effects of Diffraction(2D SAW Propagation)

Courtesy of Fujitsu Labs.

Page 22: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

(a) For Wide Aperture (b) Narrow Aperture

For Weighted IDT

Variation with Aperture Size

Page 23: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

DAT

CD player Amp.

E

SR

SLR

Power source Load

E

SR

SLR

Power source Load

?

Low Frequency Design

High Frequency DesignHigh Zin and Low Zout for Minimum Interference

RL=RS for Maximum Power Transfer

How about this case?

Page 24: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Triple Transit Echo (TTE)Interdigital Transducers (IDT)

• Mechanical Reflection + Electrical Regeneration Mutual-Connection Dependent

• Trade-Off: TTE Insertion Loss• Intrinsic for Bidirectional IDTs

Page 25: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

504540353025201510

50

-0.2 -0.1 0 0.1 0.2

Inse

rtion

loss

in d

B

Relative FrequencyS21 S21

0

Influence of TTE

Page 26: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Bragg Reflection

p

Bragg Condition

p=n

Double-Electrode IDT

Single-Electrode IDT

Page 27: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

absorber absorber

Guard electrode

Transversal SAW Filter

ꞏAbsorbers for Suppression of Reflection at Substrate Edges

ꞏDummy Electrode for Suppression of Reflection and Charge Concentration at Edges

ꞏGuard Electrode for Suppression of EM Feedthrough

Page 28: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

•SAW Transversal Filter•SAW Unidirectional IDT Filters•SAW Resonator Filters•Duplexers•Oscillators•SAW Wireless Tags and Sensors

Contents

Page 29: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

PLL/VCO

DuplexerIF-BPFRF-BPF

AntennaLNA

PA

PLL/VCO

A/D

D/A

A/D

D/A I

Q

I

Q

PLL/VCO

IF-BPFRF-BPF

Heterodyne Transceiver

Red:SAW Devices

Page 30: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Single Phase Unidirectional Transducer (SPUDTs)

(b) Embedded Reflector(Complex but Wideband)

(a) Combination with Reflector(Simple but Narrowband)

• TTE Suppression• Low Loss• Frequency Response Weighting for Excitation Profile

• Reflection Bandwidth < IDT Bandwidth Reflector Weighting

Independent Weighting to both Excitation and Reflection

Page 31: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

pI

CtCrCtCr

For +X Direction, m22 )12()(2 npI

X

For -X Direction

Unidirectional Cond. 8/ ,2/

Unidirectional Condition

Ct: Excitation Center

Cr: Reflection Center

Page 32: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

(d) With Excit. & Ref.

(b) With Excit., Ref.-Less

(c) Excit.-Less, With Ref.

(a) Excit.-Less, Ref.-Less

For Independent Weighting to Excitation and Reflection

EWC(Electrode-Width-Control)/SPUDT

Page 33: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Scat

terin

g C

oeffi

cien

t (dB

)

-40-35-30-25-20-15-10-50

0.8 0.85 0.9 0.95 1 1.05 1.1 1.15 1.2Relative Frequency

=90o

=0oLT=50pI

LI=20pI

pI=0.02

Filter Response with Reduced TTE

Low Loss and Suppressed TTE

Page 34: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Resonant SPUDT (R-SPUDTs)

Reversed Reflection WeightingDirect Pulse

Multiple Echoes

Extension of Impulse Response

Page 35: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

With Reflection

Without Reflection

• Skirt Characteristics are Defined by Impulse Response Length

• Out-of-Band Characteristics are Defined by Excitation Profile

Page 36: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

-60

-50

-40

-30

-20

-10

0

0.8 0.85 0.9 0.95 1 1.05 1.1 1.15 1.220

30

40

50

60

70

80

Relative Frequency

Scat

terin

g C

oeffi

cien

t (dB

)

Gro

up D

elay

/

p

|S21|LT=0LI=34pI pI|max=0.1

Designed Example

Sharp Passband Shape + Flat Group Delay

Page 37: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

-1-0.8-0.6-0.4-0.2

00.20.40.60.8

1

2 4 6 8 10 12 14 16 18 20

Excitation

ReflectionForward

Relative Position

Wei

ghtin

g Fu

nctio

n

Optimized weighted function

Page 38: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Courtesy of EPCOS AG

Weak Resonant SPUDT Filter

Page 39: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Courtesy of EPCOS AG

Strong Resonant SPUDT Filter

Page 40: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

•SAW Transversal Filter•SAW Unidirectional IDT Filters•SAW Resonator Filters•Duplexers•Oscillators•SAW Wireless Tags and Sensors

Contents

Page 41: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

DuplexerRF-BPF

AntennaLNA

PA

PLL/VCO

A/D

D/A

A/D

D/A I

Q

I

Q

PLL/VCO

RF-BPF

Homodyne Transceiver

• Circuit Simplification Reducing Component Number• No Image Signal Relaxing Specs to RF Filters

Page 42: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

(a) 1-Port Resonator

(b) 2-Port Resonator Filter

SAW Resonator

Page 43: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Piezoelectric Material

+

-

C0

Mk-1

V F

i v

C0

Lm

Rm

Cm

Analogies between VF and Iv reduce toML, R, k 1/C

(a) Electric + Mechanical Circuit

Application of Electric Field to Piezoelectric Material,

(b) Electrical Equiv. Circuit

VFvdtkvdtdvM

Page 44: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

(a) Electrical Equiv. Circuit (b) Equiv. Mechanical Circuit

•Resonance Frequency r=1/ CmLm•Anti-Resonance Frequency a=1/ Lm(Cm

-1+C0-1)-1

•Resonance Q (Steepness of Resonance) Q=rLm/Rm

•Capacitance Ratio (Weakness of Piezoelectricity)C0Cma/r)2-1]-1

Determine Insertion Loss and Skirt Characteristics

Determine Insertion Loss and Bandwidth

k

M

F

k0C0

Lm

Rm

Cm

Page 45: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

-0.6-0.4-0.20

0.20.40.60.81

0.96 0.98 1 1.02 1.04

Adm

ittan

ce [S

]

Frequency [GHz]

fr fa

•Resonance Frequency r=1/ CmLm•Anti-Resonance Frequency a=1/ Lm(Cm

-1+C0-1)-1

Page 46: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Transverse Mode

Frequency

Adm

ittan

ce

r a

B

GIn-harmonic Resonance

Page 47: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Countermeasure

Influence of Diffraction

Transverse Modes

Page 48: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

10

100

1k

428 430 432 434 436 438

Impe

danc

e (

)

Frequency (MHz)

(a)

(b)

(c)

SAW Resonator on Quartz

Page 49: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

433.00 MHz

431.625 MHz

434.635 MHz

Field Distribution Observed by Laser Probe

Page 50: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Power Leakage to Bus Bar Regions

Page 51: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Reduction of Excitation Efficiency for Higher ModesLoss Increase by Scattering at Discontinuities

IDT Apodize

Page 52: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Dummy Electrode Weighting

Spurious Modes Penetration ⇒Leakage to Bus Bar Regions

[Dummy]Reflection at Gaps ⇒Strong Wave Confinement

T.Omori, K.Matsuda, N.Yokoyama, K.Hashimoto, and M.Yamaguchi, “Suppression of Transverse Mode Responses in Ultra-Wideband SAW Resonators Fabricated on a Cu-grating/15oYX-LiNbO3Structure”, IEEE Trans. Ultrason., Ferroelec., and Freq. Contr., 54, 10 (2007) pp. 1943-1948.

Page 53: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Piston Mode BAW Resonator

Active Region

xFrame Frame

R.Thalhammer, J.Kaitila, S.Zieglmeier, and L.Elbrecht, “Spurious mode suppression in BAW resonators,” Proc. IEEE Ultrason. Symp. (2006) pp. 456-459

Page 54: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

M.Solal , J.Gratier, R.Aigner, K.Gamble, B.Abbott, T.Kook, A.Chen, and K.Steiner, “Transverse modes suppression and loss reduction for buried electrodes SAW devices,” Proc. IEEE Ultrason. Symp. (2010) pp. 624-628

Piston Mode SAW Resonator

Page 55: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Ladder-Type SAW Filter

Topology

• Low Loss• High Power Durability• Moderate Out-of-Band Rejection

Page 56: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

r a

Inse

rtion

Los

s (dB

)

Frequency Inse

rtion

Los

s (dB

)

Frequency

r a

Parallel-ConnectionSeries-Connection

YsYp

Ys

Yp Yp

Inse

rtion

Los

s (dB

)

Frequency

sp

p s

r

ar

a

-Connection

Null Generation

at Both Sides

Page 57: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Performance of Ladder-Type SAW Filter

W-CDMA-Rx

-50-45-40-35-30-25-20-15-10-50

1900 2000 2100 2200 2300 2400-5

-4

-3

-2

-1

0

Tx Rx

Frequency (MHz)

Fujitsu FAR-F6CP-2G1400-L21M

Scat

terin

g Pa

ram

eter

S21

(dB

)

Scat

terin

g Pa

ram

eter

S21

(dB

)

Page 58: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

• Good Out-of-Band Rejection

• Balun Function• Transformer Function• Low Loss• Lower Power Durability

Symmetrical & Anti-

symmetricalResonances

Double Mode SAW (DMS) Filter

Inse

rtio

n lo

ss (d

B)

Frequency

rs ar

Electrically Isolated I/O

Page 59: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Structure of Pitch-Modulated IDT & ReflectorConventional Structure Pitch-Modulated Structure

IDT IDTREFECTOR

Modulated

ModulatedGap Controlled

Presented at IEEE 2004 UFFC Conf.

Page 60: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

-8-7-6-5-4-3-2-10

800 850 900 950 1000 1050-80-70-60-50-40-30-20-10

0

Frequency [MHz]

Scat

terin

g pa

ram

eter

. S21

[dB

]

Scat

terin

g pa

ram

eter

. S21

[dB

]

DMS Filter with Modulated Structure

Page 61: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Integrated RF Circuit

Current Antenna and RF Stage are Unbalanced

(a) Balanced I/O

(b) Unbalanced I/O

+

-

+-

Page 62: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Front-endBPF LNA

Inter-stageBPF IF-BPFMixer

Front-endBPF LNA IF-BPFMixer

Balun IF-Amp

IF-Amp

Discrete SAW Filter & Balun

Inter-stageBPF

SAW Filter with Balun Function

Page 63: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Vout+

Vout-

Vin

DMS Filter (Ideally No Common Signal)

Acoustically Coupled but Electrically Isolated

Common Signal Generation by Parasitics

Page 64: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Vout+

Vout-

Vin

Vin

Vout+Vout-

Z-conversion by DMS Filter

Page 65: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

•SAW Transversal Filter•SAW Unidirectional IDT Filters•SAW Resonator Filters•Duplexers•Oscillators•SAW Wireless Tags and Sensors

Contents

Page 66: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Role of Duplexer in FDD Transceiver

Power Amplifier

Low Noise Amplifier

Detection of Weak Rx Signal

Efficient Excitation of Tx Signal

-100 dBm

+25 dBm

Tx->Rx Leakage Suppression in Tx Band = DuplexerMinimization of RF Power Loss

Jammer (-15 dBm Max)

Page 67: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Taiyo Yuden FAR-D6CZ-1G9600-D1XC

Page 68: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Avago’s FBAR PCS DuplexerACMD-7402 (3.8*3.8*1.3mm)

Page 69: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Frequency Allocation

800 MHz Bands

1.5~2.5 GHz Bands

3.5 GHz Ban

69

Page 70: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

RF Front End of One Generation Before….

PA ModulesDuplexers

Filter Array

Page 71: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Relation Between Stress T and Strain S

Elastic Deformation

0

Plastic Deformation

Fracture

Linear Region

Stress, T

Stra

in, S

Page 72: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

4/}])2cos{(})2[cos{(

2/}])cos{(})[cos{(

4/4/)2cos(

cos}2/{

cos}4/{

3/)coscos(

2/)coscos()coscos(

babab2

a)3(

bababa)2(

2a

)2(a

2)2(b

2)3()1(b

a2)3()1(

a

3bbaa

)3(

2bbaa

)2(2baa

)1(

ttTTs

ttTTs

TstTs

tTssT

tTssT

tTtTs

tTtTstTtTsS

a

a

a

Case 2: When T=Tacos(at)+Tbcos(bt) (|Ta|>>|Tb|),

Linear Vibration+Gain Compression

H2+DC Generation

IMD: Inter-Modulation Distortion

IMD2 Generation

IMD3 Generation

Page 73: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Spectrum Regrowth in PA and DPX= Self Mixing of Tx Signals

Jammer Signal Emission Toward Adjacent Channels

Page 74: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Inter Modulation Distortion in Nonlinear Circuit for WCDMA System

Sign

al in

tens

ity

fa

fb2fa-fb(3rd order)

Tx filter Rx filter

fb+fa(2nd order)

fb-fa(2nd order)

2fa+fb(3rd order)

Rx signal + Nonlinear distortion product

Jammer Jammer

Band1Tx: 1920-1980 MHzRx: 2110-2170 MHz

190MHz 1730 - 1790 MHz 4030 – 4150 MHz

5950 – 6010 MHz

Band2Tx: 1850-1910 MHzRx: 1930-1990 MHz

80MHz 1770 - 1830 MHz 3780 – 3900 MHz

5630 – 5810 MHz

Jammer Frequency

Jammer Frequency

Page 75: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

3)3(2)2()1(

31

21 TsTsTsS

0 Stress, TSt

rain

, S

Only True for Asymmetric Cases

In Elastic Region (w/o Hysteresis)

0 Stress, T

Stra

in, S

For Symmetric Cases,s(2n)=0

3)3()1(

31 TsTsS

Page 76: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Tx Rx

Tx band:53 dB typ.

Rx band:48 dB typ.

Tx Rx

Tx band:59 dB typ.

Rx band:53 dB typ.

FBAR (Tx) + DMS (Rx) Duplexer

DMS Offers Balanced Output

Page 77: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

R.Ruby and M.Gat, “FBAR Filters- 2012,” Proc. 2012 International Symposium on Acoustic Wave Devices for Future Mobile Communications) G1 -1~4

With Improved Temperature Stability

Page 78: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

LT/Sapphire Wafer Bonding

M. Miura, T. Matsuda, Y. Satoh、M. Ueda, O. Ikata, Y. Ebata, and H.Takagi, “Temperature Compensated LiTaO3/Sapphire Bonded SAW Substrate with Low Loss and High Coupling Factor Suitable for US-PCS Application,” Proc. IEEE Ultrasonics Symposium (2004) pp. 1322-1325

LT

Sapphire

IDT

Page 79: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Performance Example

M. Miura, T. Matsuda, Y. Satoh、M. Ueda, O. Ikata, Y. Ebata, and H.Takagi, “Temperature Compensated LiTaO3/Sapphire Bonded SAW Substrate with Low Loss and High Coupling Factor Suitable for US-PCS Application,” Proc. IEEE Ultrasonics Symposium (2004) pp. 1322-1325

Page 80: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

80M Kadota, N.Takaeshi, N.Taniguchi, E.Takata, M.Miura, K.Nishiyama, T.Hada, and T.Komura, “Surface Acoustic Wave Duplexer for US Personal Communication Services with Good Temperature Characteristics,” Jpn. J. Appl. Phys., 44 6B (2005) pp. 4527-4531

SiO2 On-Top DepositionSiO2: Stiffness Increase with Temperature

Page 81: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

M Kadota, N.Takaeshi, N.Taniguchi, E.Takata, M.Miura, K.Nishiyama, T.Hada, and T.Komura, “Surface Acoustic Wave Duplexer for US Personal Communication Services with Good Temperature Characteristics,” Jpn. J. Appl. Phys., 44 6B (2005) pp. 4527-4531

Performance Example

Page 82: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Rich Ruby, “A Decade of FBAR Success and What is Needed for Another Successful Decade,” Proc. SPAWDA (2011) pp. 365-369

Use of SiO2 for Temperature Compensation

Page 83: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

5

-25-20-15-10-50

68 70 72 74 76 78

-

FWHM of 4 peak (cm-1)

-25-20-15-10-505

80 85 90 95 100

TC

F (p

pm/o C

)

FWHM of 3 peak (cm-1)

TC

F (p

pm/o C

)

Relation Between FTIR FWHM and TCF in

SiO2 Properties Change with Deposition Condition

Page 84: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Use of SiOF FimsAnticipated from FTIR Data⇒ Experimental Verification

S.Matsuda, M.Hara, M.Miura, T.Matsuda, M.Ueda, Y.Satoh, and K.Hashimoto, “Use of Fluorine Doped Silicon Oxide for Temperature Compensation of Radio Frequency Surface Acoustic Wave Devices,” IEEE Trans. Ultrason., Ferroelec., and Freq. Contr., 59, 1 (2012) pp. 135-138

Page 85: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Material CharacterizationQuantitative Evaluation of Acoustic Properties of Thin Films with High Accuracy

Ultrasonic Microscope System

Page 86: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Dependence of SAW Vel. on SiO2 (1 m)/ (001)Si SurfaceK.Sakamoto, S.Suzuki, T.Omori, K.Hashimoto, J.Kushibiki, and S.Matsuda, “Characterization of Elastic Properties of SiO2 Thin Films by Ultrasonic Microscopy,” Proc. IEEE Ultrason. Symp. (2014) pp. 893-896

f=225 MHz

Page 87: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Piezo-LayerMetal Metal

Use of Extremely Thin Piezo-Layer

High z Layer (AlN)

Base-Substrate (Si)

low z Layer (SiO2)

Energy Confinement in Thin Piezo-Layer

K2 EnhancementBAW Loss Reduction

Page 88: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Murata’s IHP SAW Duplexer

IL TX 1.5 dB, Rx: 1.9 dB

TCF: 8 ppm/oC

Iso.: 56 dB for Tx and 60 for Rx

Page 89: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Temperature Stability

T.Takai, H.Iwamoto, Y.Takamine, H.Yamazaki, T.Fuyutsume, H.Kyoya, T.Nakao, H.Kando, M.Hiramoto, T.Toi, M.Koshinoand N.Nakajima “Incredible High Performance SAW resonator on Novel Multi-layerdSubstrate”, Proc. IEEE Ultrason. Symp. (2016)

Conventional LT

IHP

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For Further Increase in Channel Capacity

SNR1log2 BCB: Bandwidth

SNR1log2 NBCN: No. Antenna

ifon X

Multi-Input Multi-Output(MIMO)

Page 91: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Carrier Aggregation

ifon X

Requirements to Pico Cell Duplexer?

Pico Cell

Band 1 Band 7

Page 92: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

4

Frequency

Spec

trum

123 5678 N

=2/T

SPConv. IFFT FFT PS

Conv.PSConv.

SPConv.Transmission

OFDMA System Setup

Orthogonal Frequency Division Multiple Access, OFDMA

Page 93: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Peak to Average Power Ratio (PAPR)

Use of Effective Coding = Increase of PAPR (Random Variation in time)Necessity of Linearity ImprovementNecessity of Durability Improvement for Peak Power

Page 94: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Power Durability

Generation of Voids and Hillocks = Acousto-Migration

Where is the Weakest?

Increase in Substrate Temperature for Given Input Power

Page 95: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Life Time Modelling kTEP /expTF

,, E:constant, k: Boltzmann Constant, T: Absolute Temperature

Page 96: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

・Electrode Material and Structure・Heat Reduction (Loss Reduction)・Improving Thermal Conductivity: Wafer Bonding, ScAlN?・Reduction of Power Density

For High Power?

2Ys 2Ys

Ys Half Input Voltage

Doubled Electrode Area

Increase in Chip Size…

Page 97: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Peak to Average Power Ratio (PAPR)

Increase in Peak Power → Cause of Different Failure Mechanism

Page 98: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

•SAW Transversal Filter•SAW Unidirectional IDT Filters•SAW Resonator Filters•Duplexers•Oscillators•SAW Wireless Tags and Sensors

Contents

Page 99: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

C2

eout

C1

Quartz Oscillation Circuit

Quartz Tuning Fork

215 =32,768Hz Osc. Counting 215 Pulses Gives 1 Sec.

ppm 10day 1sec. 1

How Accurate?

Use of Acoustic Vibration

High Quality Factor = Long Vibration Sustain Insensitive to Noise

High Temperature Stability

Page 100: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Global Positioning System (GPS)

2222 )()()( nnnn zzyyxxd

xn, yn, zn : position of the n-th satellitedn: distance from the n-th satellite

Present position (x, y, z) is given by solvingNn ,,2,1

Page 101: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Oscillation Spectrum (Phase Noise)Conversion of AM Noise to PM Noise via Saturation

H()

1/f Noise (Flicker)Thermal

(Johnson)

Long Term Stability (Ageing)Mid Term Stability (Temp. Drift)Short Term Stability (Fluctuation)

Page 102: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Frequency Synthesizer (v=Ms/N)

Phase-Locked Loop (PLL)

• Use of Stable s ⇒Accurate & Stable

• Programmable Divider ⇒ Tunable

VVCO

SedLPFN Counter

M Counter

Loop Filter

H() VCO (Voltage Controlled Oscillator) Determines Thermal Noise Level

Phase Noise Deterioration at Counter Change

Page 103: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Influence of Phase Noise

BPF s(t)c(t)mixer

s(t)

c(t)

c

Mixing with Local Oscillation c(t) with Noise

s1(t)c(t) s2(t)c(t)Conversion of Thermal and 1/f Noise in Adjacent Channel to Desired Channel

Spectrum After Mixing

Page 104: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Base-BandProcessing

High Speed ADC

Software Defined Radio (SDR)

Multiple Standard (GSM, UMTS, GPS, etc.) Support by Software Loading from HDD

System Upgrade by Software Download

ADC: Analog-to-Digital Converter

Data Stream

Page 105: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Base-BandProcessing

High Speed ADC

For SDR Realization

frequency

Spec

trum

Target SignalExtremely Large Dynamic Range Necessary

High Speed & Extremely Large Dynamic Range ADC Possible?

Data Stream

Page 106: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

0 0.5 1 1.5 2

Sign

al A

mpl

itude

time

Sampling Theorem

Low Pass Filtering of Periodically Sampled DataRecovery of Original Signal

Sampled Signal

Page 107: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Signal with Thermal Noise

After Digitization

Pulse Miss-Count

After Digitization with Hysteresis

t

2Vc

Jitter

Jitter Generation by Thermal Noise

Page 108: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Influence of Jitter to High Speed ADC

Jitter Causes Amplitude Fluctuation (Error)

http://www.analog.com/jp/digital-to-analog-converters/da-

converters/products/tutorials/CU_tutorials_MT-007/resources/fca.html

Influence of Jitter Significant at High Frequency

Page 109: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Influence of Jitter and Freq. to SNR

http://www.analog.com/jp/digital-to-analog-converters/da-

converters/products/tutorials/CU_tutorials_MT-007/resources/fca.html

Page 110: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

How to Reduce Jitters• Low Jitter (Low Noise) Oscillation Using

High Q Resonators

cf: Atomic Clock (Very Accurate But Not Precise)

Stabilization by Quartz Oscillator (Very Precise But Not Accurate Enough)

Very Precise and Very Accurate Oscillation

Page 111: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

•SAW Transversal Filter•SAW Unidirectional IDT Filters•SAW Resonator Filters•Duplexers•Oscillators•SAW Wireless Tags and Sensors

Contents

Page 112: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

AT-cut Quartz

Quartz Micro-Balance (QMB)

• Temperature Stability• Phase (or Frequency) Output High Resolution• Low Price

Mass Loading

Sensor Applications: Physical (Film Thickness, Pressure), Chemical(Gas, Liquid), Bio

Page 113: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Vout

Vin

Piezo-Substrate

IDT

SAW

• High f (f K fm) High Sensitivity• Moderate Temperature Stability• Surface Protection (Packaging) ?

SAW Sensor

Area 1 mm2 & f=1 GHz give K f ~ 107 / kg 1 ppm of f deviation=Resolution 0.1 pg.

Page 114: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

SAW Sensor Configuration

Frequency Detection

Phase Detection~m

f ~m

Page 115: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

SAW Chemical Sensor

• Sensitive Layer: A calixarene (10 nm)• Object: tetrachloroethene• f0: 434 MHz

Time [min]Freq

uenc

y D

evia

tion

[Hz]

0

-200

-400

-6000 10 20 30

Con

tent

[ppm

]

0

20

40

60

Page 116: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Pattern Recognisition with Sensor Array

Sensor : Sensitive FilmA Calix[4]resorcinearene 1B Calix[4]resorcinearene 2C Cyclodextrine-functiona-

lized polymer 1D Cyclodextrine-functiona-

lized polymer 2

C DA B

Sensor Array

p-xylenem-xylene

humidity

Page 117: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

What is SAW ID-TAG?

Antenna

Transceiver

• Large Group Delay (Separation with Environmental Echoes)

• Wireless, Batteryless

Page 118: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Separation of SAW Signal in Time Domain

Excited Signal

Environmental Echo

Sensor Echo

RF Response

time

Page 119: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Which Frequency?

•5.2 GHz (ISM Band)Wideband (100MHz), Short Accessible Distance (<1m), Hard to Realize SAW Devices

•2.45 GHz (ISM Band) Wideband(22MHz), Short Accessible Distance (2-3m), Price of SAW Devices?

•433.92 MHz (RKE Band) Narrowband(1.7MHz), Long Accessible Distance (>10m), Low SAW Device Cost

Page 120: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

SAW ID Tag with 5 reflectors in one track (f0 = 2.45 GHz) using pulse position coding

Pulse position coding schema

Page 121: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

OIS - W

Baumer Ident (2.45 GHz ISM)

Page 122: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

Brake temperature of a train entering a station

60,00

70,00

80,00

90,00

100,00

Time

Tem

pera

ture

°C

reader antenna

Brake (with attached SAW temperature transponder, not seen)

Page 123: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

The dynamic range of monitoringthe torque with SAW can be up to several tenths of kHz

SAW Torque Sensor

strain in ‰

ph

ase

dif

fere

nc

e in

de

g.

0

50

100

150

200

150

0 0.05 0.10 0.15 0.20

SAWsensors

rotatingshaft

Tx antennas

Rx antennas

measurement set-up

Page 124: April 2, 2019 Introduction to Surface Acoustic Wave (SAW ...Surface Acoustic Wave (SAW) Device Vout Vin Piezoelectric substrate Interdigital Transducers (IDT) SAW • Mass Production

SAW pressure sensor

diaphragm

adhesive

cover-plateclosed cavity withreference-pressure

antenna

1.001.201.401.601.802.002.202.402.602.803.00

14:30

:5514

:30:59

14:31

:0414

:31:09

14:31

:1314

:31:18

14:31

:2214

:31:27

14:31

:3214

:31:36

14:31

:41

pressure[Bar]

time

Two Track Railway Crossing

Adjacent Water Channel