Industry-Relevant Research and Development in S. Tanaka Lab

Shuji Tanaka, Professor, IEEE FellowDepartment of RoboticsMicrosystem Integration CenterTohoku Universitytanaka@mems.mech.tohoku.ac.jp

mems tohoku

Self-introduction of S. Tanaka Laboratory

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We are international and prefer diversity.• Our members come from 10 different countries; Japan,

China, Vietnam, Pakistan, Germany, Indonesia, Algeria,Chile, France and India.

• There are 9 women.• The age of our members

ranges from 20 to 75. Thereare 7 senior members olderthan 60 years.(As of March 2018)

Please visit our website!

Division of Mechanical Engineering

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Material Science: #43

Mathematics: #101-150

Mechanical Engineering: #38We are World Premier InternationalDivision, attracting students all overthe world.

QS World Ranking 2019

MEMS Facilities in Aobayama Campus

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• From proof-of-concept on small pieces to prototype development on 4 or6 inch wafers

• Prototyped devices in Microsystem Integration Center can be basicallyutilized for business, i.e. as commercial samples and provisionalproducts.

• For mass-production in small-to-medium volume, developed technologycan be smoothly transferred to our partner foundry, MEMS Core inSendai, Japan.

S. Tanaka Lab’s cleanroom

Micro/Nano-Machining Research & Education Center

Microsystem Integration Center

Small piece

4 inch wafer

6 inch wafer

We can work with and support industry at any R&D phases.

Div. Mech. Eng.

S. Tanaka Laboratory: Research Topics

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Physical world

Human world

Sensing

Actuation

Micro/Nano system technology

Connection

Cyber world

Virtual world

Tactile sensor, Gyroscope, Ultrasonic sensor, Microphone

Micromirror, Optical stage,RF MEMS switch

e.g.

e.g.

e.g. Acoustic wave filter

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NaturallyUnconsciouslyComfortablyAffordably

RoboticsVR

AR

IoT

System integration

Functional materials

MEMSCore competence

Integration technology,Wafer-level packaging,Piezoelectric thin films,Microfabrication tools

e.g.

Presented by Prof. Muroyama

A part of our ongoing research will be introduced…

Laser Speckle Reduction Device (Ricoh)

7 in JSTnews, April 2019

A nanofabricated optical phaseplate is driven by a PZT MEMSactuator.

Mr. Fujimura at Ricoh Industrial Solutions, Visiting Researcher of S. Tanaka Lab

Outstanding poster paper award in IDW ‘18

Micromirror Device (Stanley Electric)

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Stanley, 応用物理学会2014春, 17p-E9-7

Resonant axis:±14°

Non-resonant axis:±8°at 60 V

Stanley, Tokyo Motor Show 2017

Epitaxial PZT Family on Silicon

SRO(0.393 nm)

Si(0.5431 nm)

YSZ(0.5139 nm)

CeO2(0.5411 nm)

LSCO (0.3805 nm)(√2LSCO = 0.5380 nm)

PZT(a, b-axis length: 0.404 nm,c-axis length: 0.415 nm)

45 ˚

[100] [010]

[001

]

9 Epitaxial structure of PZT on Si

20 25 30 35 40 45 50 55 60 65 70 75 80 852θ[deg]

Slow cooling

CeO2(200)

PZT(200)

SRO (200)

PZT(002)

P

PZT(003)Si (400)

YSZ(200)

PZT(002)&(200)

PZ

PZT(003) Si (400)

PZT(110)

SRO (200)

Inte

nsity

[cps

] (lo

garit

hmic

disp

lay)

Fast cooling(a)PZT(001)&(100)

PZT(001)&(100)

c-axis (not a-axis) orientation is obtained by fast cooling after sputtering.

XRD spectrum of epi-PZT on Si

S. Yoshida … S. Tanaka, IEEE Trans. Ultrason. Feroelectr. Freq. Contr., 61 (2014) 1552-1558

Comparison of Sputtered PZT Thin Films on Si

10[1] S. H. Baek … B. Eom, Science 334, 958 (2011) [2] F. Calame, P. Muralt, Appl. Phys. Lett. 90, 062907 (2007)[3] N. Ledermann et al., Sens. Actuators A, 105, 162 (2003)

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ε33e31,f ε33

pMUT for Range Finder and Fingerprint Sensor

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Z. Zhou, S. Yoshida, S. Tanaka, Transducers 2017

“I attempted to fool the new Samsung Galaxy S10's ultrasonic fingerprint scanner by using 3D printing. I succeeded.” by darkshark (April 4, 2019)

Vivo’s XPlay 7 (2017)

Qualcomm’s fingerprint sensor

In-display ultrasonic finger print sensor using pMUT

Samsung’snew Galaxy S10

↓

3D-printed fake fingerprint

Z. Liu, S. Yoshida, S. Tanaka, Transducers 2019

pMUT using Epi-PZT2

mm

dee

p

Sputter Tool for Epi PZT

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Epi-PZT buffer layer on 4 inch wafer prepared by sequential

sputter depositionOriginally-designed sputter tool for Epi-PZT in Nishizawa Center

We are working with our customers for the development of a practical sputter tool as well as pMUT.

N. Nishizawa … S. Tanaka,Trans. IEEJ SM, 136 (2016) 437-442

ALD Tool for Multiple Materials

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Our ALD tool has been commercialized by TechnoFine, where our former student is working, and 4 tools were shipped to date.

A high-temperature ALD processmonitor using Langasite is alsobeing developed with a startup.

The ALD tool was used forcollaboration with multiplecustomers.

BAW Filter: Most Growing MEMS

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Million US$

http://www.yole.fr/iso_album/illus_status_mems_industry_top_mems_ranking_yole_may2018.jpg

1st Broadcom (former Avago Technologies)

5th Qorvo (TriQuint Semiconductor + RF Micro Device)

田中秀治, BroadcomをMEMS売上高トップにしたデバイスとは,日経 xTECH 2018/07/09

BAW/SAW Filters in Smartphone

teardown.com

EE Times

SAW filter

RF frontend (Amplifiers + Filters)Avago, Skyworks and TriQuint

Power amplifierSwitch

Apple iPhone 6 Plus Apple iPhone X

Broadcom and Skyworks (partly RF360) are adopted in iPhone X.

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Continuous Requirements for BAW/SAW Filters

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Band 25 Tx filterT. Takai et al. (Murata Mfg.), IEEE IMS 2016

Up link: 1850〜1915 MHz (BW 65 MHz)Down link: 1930〜1995 MHz (BW 65 MHz)Guard band: 15 MHz → Extremely narrow

Low band Mid band1 GHz 3 GHz 4 GHz 5 GHz

600/700 MHz 3.3~4.2 MHz 4.4~5.0 GHzBand n77 3.3~4.2 GHzBand n78 3.3~3.8 GHzBand n79 4.4~5.0 GHz

Balazs Bertenyi (Nokia),Chairman of 3GPP RAN

• Lager power handling ← LTE (Overlap of subcarrier)• Smaller nonlinearity (Inter Modulation Distortion) ← Carrier aggregation• Improvement of basic performance (IL, cut-off characteristic and TCF)

← Difficult-to-deal bands (e.g. LTE Band 25 and Band 11+21)• Higher frequency for 5G (3.5~5 GHz)

Fever of BAW/SAW is Crazy in China.

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RF front-end modules with SAW/BAW filters are dominated by American and Japanese companies.SAWMurata Mfg., Skyworks (former Panasonic),RF360 (former Epcos), Qorvo (former TriQuint),Taiyo Yuden (former Fujitsu)BAW (FBAR and SMR)Broadcom (former Avago), Qorvo, RF360,Taiyo Yuden, Skyworks

ROFS Microsystems (诺思(天津)微系統)Mianyang City (四川省綿陽市) has decided to invest 12.8B RMB in ROFSMicrosystems to construct an FBAR factory. A revenue of 15B RMB, aproduction over 10B devices and an employment over 3000 are expected.

San’an Optoelectronics (三安光電)San’an Optoelectronics has decided 33.3B RMB investment over 7 years toconstruct factories of LED, power amplifiers, SAW/BAW filters etc. inQuanzhou City (福建省泉州市).

Photograph: Reuters

SAW or BAW?

Andreas Link, Phil Warder (TriQuint Semiconductor), “Golden Age for Filter Design,”IEEE Microwave Magazine, August 2015, pp. 60-72

180.5 GHz 1.5 GHz 2.5 GHz

Hetero Acoustic Layer SAW

New Types of SAW Device

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BAW

Longitudinal wave

Fast shear wave

Slow shear wave

SAW

Longitudinal leaky SAW

Leaky SAW

Rayleigh SAW

Phas

e ve

loci

ty

High velocity and high coupling, but leaky (lossy)

Confined near surfaceby HAL structure

Acoustic bulk radiation (loss)

LSAW/LLSAW

HAL (Hetero Acoustic Layer) SAW devices

Thinned LT or LN (t < λ)

Conventional SAW device

LT or LN

SiO2etc.Si, quartz,

sapphire etc. Si, quartz, sapphire etc

Thin LT/Quartz Hetero Acoustic Layer SAW

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M. Kadota, S. Tanaka, IEEE International Ultrasonics Symposium 2017

400 500 600

BW 5.0%Z ratio 82 dBλ 7.76 µm

Cu/42oYX-LT

Impe

danc

e [Ω

] Cu/20oYX-LT/40oY90oXquartz

800 900 10001

10

100

1000

10000

100000

Frequency [MHz]

BW 4.2%Z ratio 51 dBλ 3.78 µm

C

51 dB

82 dB

Quartz

LT (typically 1 μm)

Sigle digit TCF of LT/quartz HAL SAWIEEE IFCS 2018

“HAL SAW” is our brand name,being licensed to our customer.

↑The production technology of HAL wafers is being developed with a local company.

Conclusive Message

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• The introduction of a part of our ongoing collaborative projectsshows our strong commitment and contributions to industry.

• Our customers include domestic listed company, foreigncompany, small local company and startup.

• Another fact is about 200 company×day guests to ourlaboratory in the last year.

Collaboration with Fraunhofer ENAS will further strengthen ourcapability of R&D, benefitting both sides and industry.

Conference for Business Development based on MEMS Technology

24-25 April 2019

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General Chair Shuji Tanaka