1

2008 Advanced Materials Characterization Workshop

M t i l h t i ti

Sponsors:

The Frederick Seitz Materials Research LaboratoryUniversity of Illinois at Urbana-Champaign

Materials characterization: the need for complementary techniques

Ivan Petrov

1

Sponsors:

Supported by the U.S. Department of Energy under grants DEFG02-07-ER46453 and DEFG02-07-ER46471© 2008 University of Illinois Board of Trustees. All rights reserved.

Why materials analysis

Material characterization at the atomic scale is needed:needed:

• In order to understand/control the synthesis processes• In order to understand why materials, micro-, and

nanosystems work or fail

Understand

2

Understand synthesis – structure/composition – properties relationship

2

Main questions to answer

1. What are the building blocks – elemental and chemical analysis

2. What is the electronic structure3. What is the arrangement of the building blocks –

crystallographic analysis4. What are the surface morphology and bulk

nanostructure – imaging from micron to sub-nanometer scale

3

nanometer scale

IonsElectrons

IonsElectrons

Primary beam (source, gun)

Secondary beam (spectrometers, detectors)

Wide variety of methods for materials analysis

ElectronsPhotons

ElectronsPhotons

4

* with ions and electrons: the sample is in vacuum** exception: scanning probe microscopy

3

5

http://www.eaglabs.com/

FSMRL Central Facilities

Comprehensive set of techniques from routine to most advanced24 h access to qualified users

Staff 16 scientists and engineers for > 40 major instruments

5. Surface Analysis1 Transmission Electron Microscopy 5. Surface AnalysisCameca IMS 5f SIMSPHI 660 AugerPHI 5400 XPSSmall-spot imaging XPSPHI TOF-SIMS(2003)Van de Graaff for ion beam analysisTandetron for ion beam analysis

6. Laser and Optical SpectroscopiesRaman spectroscopyPhotoluminescenceSpectrophotometryPump/probe spectroscopyFourier transform infra red spectroscopy

1. Transmission Electron MicroscopyPhilips CM12Vacuum Generator HB501JEOL 2010 F STEM/TEMJEOL 2011 TEMIBM Low-Energy Electron MicroscopyJEOL 2100 Cryo (2006)JEOL 2200FSTEM/STEM (2008)2. Scanning Electron MicroscopySEM/Focused ion-beam microscopyHitachi S-4700, SEM S-4800 (2008)JEOL 6060 low-vacuum SEM(2004)JEOL7000 analytical SEM (2005)

6

Fourier transform infra red spectroscopySum frequency generation EllipsometryNear-Field Scanning Optical Microscopy

7. NanofabricationElectron beam lithography/Optical lithographyClean rooms/mask alignersThin film synthesis: sputtering, evaporation, ALDWet/Dry etching: RIE, Ion millingNanotube growth furnace/Bulk crystal growthMagnetic/Electrical properties measurement

3. Scanning Probe MicroscopyDigital Instruments AFM (2) Advanced Asylum Research AFM (2) (2005)Omicron VT-UHV STMUHV-AFM4. X-ray ScatteringPhilips X'pert: high-resolution, reciprocal maps Philips X'pert: powder, pole figuresRigaku D-Max: powderLaue diffractometerEnergy Dispersive X-Ray Fluorescence

4

interaction with ANL:High-power lithium-ion battery failure mechanisms

A comprehensive characterization approach

0.5 μm

0.5 μm

Aged

0

1000

2000

3000

4000

5000

6000

7000

8000

682 683 684 685 686 687 688 689 690 691 692

Binding energy, eV

LiF

-(CF2-CH2)n-XPS, F1s spectrum50C, 60% SOC, 16 wk test

0

1000

2000

3000

4000

5000

6000

7000

8000

282 283 284 285 286 287 288 289 290 291 292 293 294

Binding Energy, eV

graphite

-(CF2-CH2)n--(CF2-CH2)n-

-(CH2)n-

-C-O-

-OCO2-

XPS, C1s spectrumPositive electrode50C, 60% SOC, 16 wk test

-C=O

-O-C=O

Imaging Spectroscopy (XPS) Elemental analysis

HRTEM Crystallography and EELS

X-ray structure

refinement

C Li

Ni All

Fresh

7

20 nm

530 535 540 545 550 555 560 565 570 575 580 585 590eV

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0.11

µm

850 860 870 880 890 900 910eV

0.00

0.02

0.04

0.06

0.08

0.10

µm

Bulk

Bulk O K-edge

Ni L-edge

Particle Surface

HRTEM, Crystallography, and EELS

(006)(113)

(110)

(018)(107)(015)

(104)

(012)

(101)

C(002)

(003)

Inte

nsity

(a.u

.)

2-theta (o)

f

nbeam[beam particles cm-

3]

Beam Flux: Jbeam= nbeamv [beam particles cm-2s-1]

Scattering cross section – one target atom

v – beam particle velocity

vΔtσ=π r2

V = vΔtσ

] p y

8

Nevents= nbeamV = nbeamvΔtσ = JbeamσΔt

σ = Nevents_per-seccond/Jbeam

5

Nevents-per-second= JbeamσNtarget

Scattering cross section – many target atoms

9

σ = Nevents-per-second

JbeamNtarget

Scattering cross section – binary target

10

Igr = Tinstr*Nevents-per-second= TinstrJbeamσgrNgr

Ior = Tinstr*Nevents-per-second=Tinstr JbeamσorNor

6

σ=π r2

Δt

Mean free path

vΔt V = vΔtσ

Nevents= ntargetV = ntargetvΔtσ

T l d di t Δt

11

λ = 1/ σ ntarget (cm/events)

Mean free path = Traveled distance

Number of events=

vΔt

ntargetvΔtσ

Scattering cross-section - σ

σ – probability that a scattering process occurs

σ = N/Jbeamntarget (events/beam particle/(atom/cm2))

N – number of events of certain type per sec (elastic, inner shell ionization, etc)Jbeam – particle beam flux (particles/sec/cm2)ntarget – target atom density (atoms/cm3)

λ – mean free path

12

λ = 1/ σ ntarget (cm/events)

If several different scattering processes can occur (λi)

1/λtotal = Σ(1/λi)

7

Beam particles properties

0.0122

13

X-ray/Matter InteractionsCoherent scattering

hν0

hν0hν1

Fluorescence

hν2 Photoelectrone-

Incoherent scattering

Incident x-ray photons XRD

XRF

XPSAuger electrone-

Coherent scattering (Thompson scattering / diffraction): incident photon hνo interacts with e- with no energy loss and no phase change

Incoherent scattering (Compton scattering): (a) e- absorbes incident energy hνo (excited photoelectron); (b) part of the energy is emitted at different energy hν1 and different phase.

50 μm – 5 cm

5 μm

Sample

Interactionvolume hν: photon

e-: electron

14

( ) p gy gy 1 p

Fluorescence (Characteristic x-rays): (a) K/L shell e- absorb incident energy hνo; (b) outer shell e-“cascade” down filling the “holes” causing secondary photons emission (hν2).

Photoelectron emission: hν0 energy is used to eject electron e- with kinetic energy = hνo – B.E.(binding energy).

Auger electron emission: (a) incident hν0 used to eject e- from atom; (b) 2nd e- “falls” to lower levels to fill the “hole”and a photon is

emitted; (c) the emitted photon is absorbed by valance e-, which ionizes and leaves the atom.

8

Electron-Beam/Matter Interactions

IncidentBeam

Characteristic

UV/Visible/IR Light

AugerEDS/WDSEDS/WDS

ImagingImaging

CLCLBackscattered

electrons (BSE)

Secondary electrons (SE)

Characteristic X-rays

Bremsstrahlung X-rays

Auger electrons

ImagingImaging

Elastic ScatterInelastic ScatterMicron-size Interaction Volume

15

Heat

Specimen Current

Is c = Ib− ηIb − δIb = Ib (1−(η+δ))

ImagingImagingIs c

Ion-Beam/Matter Interactions

Inelastic Effects

Ion beam with an energy Ei

+IElastic Effects

(+)(-) Ions

SIMSdepth profile (AES,XPS)

Implanted Particles

UV/visible photons

X-rays

SecondaryElectrons

Sputtered ParticlesT0, T*, Tn

Reflected Particles, I0,I*

T+, I+

T t

T-, I-

RBS,ERD

16

Implanted ParticlesI0

Target

Figure after G.M. McCracken, Rep. Prog Phys. 28, 241 (1975).

9

What is the arrangement of the atoms in materials -crystallographic analysis

Answering question #3

usingelastic (coherent) electron and x-ray scatteringdiffraction analysis (reciprocal space mapping)

17

Coherent diffraction by a crystal

plane normal1 1’

Ki Kd

Plane wave(x-ray or electron)

θ

d sinθ

A

B

C

d

2 2’

Ki

d

KΨ = Ψoe2πx/λ

Ψ = Ψoe2πKx

18

2n d sinλ = θBragg’s Law: by definition wave vector |Ki,d| = 1/λ

scattering vector: |K|/2 = |Kd| sinθ

|K|= 2sinθ/ λ= 1/d

10

Fundaments of diffraction

“Real” space Reciprocal spaceF

d

1/d

19

origin

Fundaments of diffraction

“Real” space Reciprocal spaceF

20

origin

11

Real and reciprocal space

21

001 zone axis 011 zone axis 111 zone axis

Real and reciprocal space in TEMTEM

Sample

Incident Electrons

< 500 nm

d

Objective Lens

Back Focal Plane

First Image Plane

Reciprocal space image

θ

22

Conjugated planes

Object Image

First Image Plane

Real space image

u v f_ _ _+ =1 1 1

Bragg’s Law

2 d sin θ = nλ

JG WEN

12

Real and reciprocal space 022002

022

50 nm50 nm

23

001 zone axis 011 zone axis 111 zone axis

Selected-area electron diffractionExample of SAED and

dark-field imaging1) Selected-area Diffraction2) Nanobeam Diffraction3) Convergent-beam electron diffraction

Major Diffraction Techniques

Selected area apertureHigh-contrast

24

Selected-area apertureaperture

JG Wen

13

Mapping reciprocal spaceFilm, fully strained

film

a// = as

a┴film

a// = as

a┴

X-ray diffraction mapping

origin

Film, fully relaxed

022002electron diffraction mapping

x = 0.67 x = 1.00

substrate

as

substrate

as

a// ≠ as

a┴

25

originsubstrate

film

MgOCeN

000 020

022002

as

Instrumentation: high resolution configuration

ω

φ ψ

x-raysource

x-raymirror

slit

4-reflectionGe(220)

monochromator

ω

2θ

slit

Crossed slits(variable slit+mask)

3-bounceanalyzercrystal

Δθ =12 arc-secΔλ/λ = 5x10-5

X’Pert XRD #1High resolution

configuration with mirror and 4-reflections

26

“Upper” detector(open: < 1o acceptance)

“Lower” detector(triple axis: 12 arc-sec acceptance)

monochromator

Mauro Sardela

• Line focus;• Parabolic x-ray mirror;• 4-reflection monochromator (12 arc-sec resolution);

• Open detector or analyzer crystal.

Programmableattenuator

14

Mapping reciprocal spaceFilm, fully strained

film

a// = as

a┴film

a// = as

a┴

X-ray diffraction mapping

origin

Film, fully relaxed

022002electron diffraction mapping

x = 0.67 x = 1.00

substrate

as

substrate

as

a// ≠ as

a┴

27

originsubstrate

film

MgOCeN

000 020

022002

as

1. What are the building blocks – elemental and chemical analysis2. What is the electronic structure

Answering questions #1 and 2

2. What is the electronic structure

usinginelastic electron and x-ray scattering(ionization and relaxation processes)

28

15

Inelastic scattering of x-rays and electrons

29

Ionization – XPS and EELSRelaxation – Auger electron spectroscopy and characteristic x-rays (EDS, WDS, XRF)

50

60

3s3p3d4s4p

Elemental analysis by inelastic processes

photoelectrons characteristic x-rays Auger electrons

20

30

40

Ato

mic

Num

ber

1s

2s

2p

30

0

10

0 200 400 600 800 1000 1200 1400

Binding Energy (eV)

16

Ionization

BE = hν (known) – KE(measured) BE = Eo(measured) – Eloss(measured)

S t t KE

Photoelectron Spectroscopy Electron Energy-Loss Spectroscopy

Conduction BandConduction Band

Valence Band

Fermi Level

Free Electron Level

Eincident X-ray = hν

Φ Conduction BandConduction Band

Valence Band

Eincident electron = Eo

Φ

Spectrometer, KE

31

1s

2s

2pBE

1s

2s

2pBE

Spectrometer, Eo, Eloss

Relaxation

Free Electron Level

Incident particle Ejected Electron Emitted Auger ElectronEmitted X-ray Photon

ionization

Conduction BandConduction Band

Valence Band

Fermi Level

2s

2p

Conduction Band

Valence Band

L2,L3

L1

32

1s K

KLL Auger electron

EAuger = E(K)- E(L2,3) - E(L2,3)

EX-ray = E(K) – E(L2,3)

17

Relative Probability of Relaxation of a K Shell Core Hole

0.8

1.0Auger Electron

Emission

0

0.2

0.4

0.6

Prob

abili

ty

X-ray Photon Emission

33

5

B Ne P Ca Mn Zn Br Zr

10 15 20 25 30 35 40 Atomic Number

Elemental Symbol

The light elements have a higher cross section for Auger electron emission.

Elemental Shifts: An Example

ScN

Metal and N Auger LinesN1s

Sc2p

Sc2sSc3p

Sc3s

First-Row Transition Metal Nitrides: ScN, TiN, VN, and CrN

VN

TiN

ScN

Cou

nts

(arb

. uni

ts)

N1s

N1s

Ti2p

V2p

Cr2p

Ti2s

V2s

Sc3s

Ti3s

V3s

Ti3p

V3p

34

1200 1000 800 600 400 200 0

CrN

C

Binding energy (eV)

N1sCr2s

Cr3s

Cr3p

Surface Science Spectra, 7, 167-280, 2000.

18

1O primary e-beam0.5-30 keV

Scanning electron microscopy (SEM)primary e-beam

100-300 keV

Scanning transmissionelectron microscopy (STEM)

Elemental analysis by electron microscopySTEM

backscattered electrons

secondary electrons<50 eV

Auger electrons

characteristic &Bremsstrahlung x-rays

characteristic &Bremsstrahlung x-rays

Probe size 0.18 nm

Thickness

35

1 μm

“Coherent”Scattering

(i.e. Interference)

“Incoherent”Scattering

i.e. Rutherford

<100 nm

energy loss spectroscopy

Ion impact collision cascadeEnergy increasing (dependent on Mi/Mt)

Threshold regimerecoils sputtered, butno (limited) cascades

Linear cascadea series of binary collisions

Spike regimehigh density of recoils

36P.Sigmund, “Sputtering by ion bombardment: theoretical concepts”, in Sputtering by particle bombardment I, edited by R. Behrish, Springer-Verlag, 1981

• Ions striking a surface interact with a number of atoms in a series collisions; • recoiled target atoms in turn collide with atom at rest generating a collision cascade.• The initial ion energy and momentum are distributed to among the target recoil atoms. • When Ei > 1 keV, the cascade is “linear”, i.e. approximated by a series of binary collisions in a stationary matrix.

19

Ion stopping cross section

[ ]( )( )) (en S EdE N N SS E Edx

= − = − +0

'( ')

E dERangeNS E

= ∫

S (E) - nuclear stopping; target atoms set in motion

Se(E)

r cm

log(

dE/d

x)

Sn(E) nuclear stopping; target atoms set in motion

Se(E) - electronic stopping; electrons set in motion

37P.Sigmund, “Sputtering by ion bombardment: theoretical concepts”, in Sputtering by particle bombardment I, edited by R. Behrish, Springer-Verlag, 1981

Sn(E)

1-2 keV

ener

gy lo

ss p

er

1-2 MeV (log E)

SRIM/TRIM simulation

1 keV Ar -> Be

Monte-Carlo simulation of ion implantation, reflection, recoil cascades, and sputtering

200 impacts

1 keV Ar -> Ti

2 impacts

38James F. Ziegler, IBM : http://www.srim.org/

1 keV Ar -> W

ion trajectories in redrecoils in green

20

keV ion impact

Used for depth profiling, sample polishing, TEM sample thinning

39

•Hard sphere model is a good approximation (atom held by bonds)•Mass ratio effects Mi/Mt important•Glancing angles increases sputtering yield, reduces mixing and damage

What are the building blocks – elemental and chemical analysis

Answering question #1

using ion-beam techniquesSecondary ion mass spectrometry

(highest detection limit)Rutherford backscattering spectrometry

(quantitative)

40

21

4. What are the surface morphology and bulk nanostructure – imaging from micron to sub-nanometer scale

Answering question #4

g g

usingScanning probe microscopy

Scanning electron microscopy

41

Split photodetector

Atomic force microscopy

42

Reflect laser off cantilever in split photodetectorMagnifies small displacements – both vertical and twisting

V.L. Mironov, Fundamental of scanning probe microscopy, (Russian Academy of Sciences, Nizhny Novgorod, 2004) http://www.ntmdt.ru

22

AFM: Surface morphology evolution during Ge MBE

43

Quantitative information of height allows histograms of slopes

Reveals surface morphology with exceptional depth of focus

Imaging with secondary electrons

44

Reactive ion etching of Al/Si(001)

23

Imaging spheres

AFM SEM

45

Answering question #1- 4

with sub-nanometer resolutionTransmission electron microscopy

46

24

•• HighHigh--resolution [110] XTEMresolution [110] XTEM

Example: Epitaxial CoSi2/Si(001)•• [110] XTEM & [001] plan[110] XTEM & [001] plan--view TEMview TEM

bcd

a

glue

•• ZZ--contrast HRcontrast HR--STEM & EELSSTEM & EELS

nits

)

nits

)

5 nm

CoSi 2

Si

O K-edge

500 600 700 800

Inte

nsity

(arb

. u

Energy loss (eV)

500 600 700 800

Inte

nsity

(arb

. u

Energy loss (eV)

a

bc

d

Co L -edge2

Co L -edge3

Lim, Greene, Petrov, JAP, 100, 013510, (2006)

JEOL 2200FS with probe aberration corrector0.1 nm STEM resolution 0.6 eV EELS

Cs corrector

25

Materials characterization: the need for complementary techniques

Typical sequence to study a set of samples:

1/ non-destructive analysis with no sample preparation to map out phase composition (XRD), surface morphology (AFM, SEM), elemental composition (RBS, EDS)2/ measure physical properties - electrical, mechanical, optical etc.3/ analysis selected samples by surface analysis (e.g. AES, XPS) depth profiling,cross-sectional SEM4/ Select key samples for plan-view and cross-section TEM to understand critical behavior physical properties

49

Examples: synthesis of Ta-N films

Rich phase system.Ta-N phase Structure Lattice constants (Å)

α-Ta cubic a = 3.3058β-Ta tetragonal a = 10.194, c = 5.313

β-TaN0 04 cubic a =10.09

0 5 10

30003020°C

3500

Weight Percent Nitrogen

L

β TaN0.04 cubic a 10.09TaN0.1 cubic a = 3.369Ta4N orthorhombic a = 5.16, b = 3.11, c = 4.94

γ-Ta2N hexagonal a = 3.0445, c = 4.9141TaN0.8 hexagonal a = 2.931, c = 2.879δ-TaN cubic a = 4.33ε-TaN hexagonal a = 5.1918(3), c = 2.9081(2)Ta5N6 hexagonal a = 5.176(6), c = 10.35(3)Ta4N5 tetragonal a = 6.83(13), c= 4.269(6)Ta3N5 orthorhombic a = 3.893, b = c = 10.264

0 10 20 30 40 50 601000

1500

2000

2500

Atomic Percent Nitrogen

Tem

pera

ture

°C

(Ta) γ-Ta N2

ε-TaN

δ-TaN

50

δ-TaN thin films (NaCl-structure) for replacing TiN.- Hard and wear resistant coatings: high hardness and mechanical strength.- Diffusion barrier layers: chemical inertness and low resistivity.

Growth of δ-TaN thin films: reactive magnetron sputtering.

26

)

Ts = 100 °Ct = 500 nm cubic TaN0.1

hexagonal γ-Ta2Ncubic δ-TaNbct-TaNx

+

*TaNx/SiO2/Si(001)GA-XRD 2θ scans TEM

111112321220

fcc bct

Phase identification

Inte

nsity

(a.u

.)

0.063

0.125

0.150

0.250

(311

)

(220

)

*

*

*(2

00)

fN2 = 1

(301

)

(200

)

(110

)

(111

)

110

200

111

200 002301400

51

20 30 40 50 60 70 80

++0.013 (211

)

(200

)

(110

)

2θ (deg)

+

(101

)

0.025 (002

)

(112

)

(110

)

0.050 δ-TaNx: ao = 0.443 nmbct-TaNx: a = 0.590 nm, c = 0.443 nm

N/Ta = 1.96

Growth phase map for TaNx

Pure Ar: tetragonal β-Ta @ Ts < 150 °Cbcc α-Ta @ Ts > 400 °C.

1000= α-Ta= α-Ta + β-Ta

= δ-TaN + ε-TaN= δ-TaN

= Ta4N+TaN0.1

= Ta4N

TaNx growth phase map

Composition measured by RBS and AES

fN2 < 0.1: three consecutive narrow lower nitride regions, defined by tilted boundaries toward higher fN2 with increasing Ts.

0.1 <fN2 < 0.3 and Ts ≤ 650 °C: single-phase δ-TaNx.

400

600

800

1000 β= β-Ta = TaN0.1

= δ-TaN + bct TaN4

= γ-Ta2N = γ-Ta2N + δ-TaN

T s (°C

)

52

0.1 <fN2 < 0.3 and Ts > 650 °C:hexagonal ε-TaNx + δ-TaNx.

Pure N2: δ-TaNx + bct-TaNx.

0 0.1 0.2 0.3 1.00

200

400

fN2

27

t = 500 nmT = 600 °C

δ-TaNx/MgO(001)K

α1

2)

t = 500 nmT 600 °C

δ-TaNx/MgO(001)

XRD ω-2θ scans GA-XRD 2θ scans

Epitaxial growth of metastable δ-TaN/MgO(001)

nten

sity

(a.u

.)

0.125

0.150

fN2

= 0.275

0.175

Ts 600 C

0 175 (1 17)

0.225 (1.31)

fN2

= 0.275 (x = 1.37)

Inte

nsity

(a.u

.)

δ-TaN (002)

Kα2

MgO

(002Ts = 600 °C

53

30 40 50 60 70 80

(113

)

(022

)

(002

)

(111

)

0.100In

2θ (deg)

0.125 (1.00)

0.175 (1.17)I

41.0 41.5 42.0 42.5 43.02θ (deg)

0.100 (0.94)

XTEM SEM

MgOTaN80 nm

300 nm

54

• Polycrystalline grains nucleate at t > 120 nm.

28

Superhardness due to coherent γ-Ta2N/δ-TaN phases

; -Ta Nγ 2; δ-TaN60 nm

Plan-view 110 zone axis

δ-TaNγ-Ta2N

100 nmMgOTaN

XTEM 110 zone axis

1 nm1 nm

fcc stacking ofTa planes

hcp stacking ofdense-packed Ta planes

FSMRL central facilities and staff

provide access and expertise for materials characterization by complementary set of techniques

1 Transmission Electron Microscopy 5 S f A l i1. Transmission Electron MicroscopyPhilips CM12Vacuum Generator HB501JEOL 2010 F STEM/TEMJEOL 2011 TEMIBM Low-Energy Electron MicroscopyJEOL 2100 Cryo (2006)JEOL 2200FSTEM/STEM (2008)2. Scanning Electron MicroscopySEM/Focused ion-beam microscopyHitachi S-4700, SEM S-4800 (2008)JEOL 6060 low-vacuum SEM(2004)JEOL7000 analytical SEM (2005)

5. Surface AnalysisCameca IMS 5f SIMSPHI 660 AugerPHI 5400 XPSSmall-spot imaging XPSPHI TOF-SIMS(2003)Van de Graaff for ion beam analysisTandetron for ion beam analysis

6. Laser and Optical SpectroscopiesRaman spectroscopyPhotoluminescenceSpectrophotometryPump/probe spectroscopy

56

3. Scanning Probe MicroscopyDigital Instruments AFM (2) Advanced Asylum Research AFM (2) (2005)Omicron VT-UHV STMUHV-AFM4. X-ray ScatteringPhilips X'pert: high-resolution, reciprocal maps Philips X'pert: powder, pole figuresRigaku D-Max: powderLaue diffractometerEnergy Dispersive X-Ray Fluorescence

p p p pyFourier transform infra red spectroscopySum frequency generation EllipsometryNear-Field Scanning Optical Microscopy

7. NanofabricationElectron beam lithography/Optical lithographyClean rooms/mask alignersThin film synthesis: sputtering, evaporation, ALDWet/Dry etching: RIE, Ion millingNanotube growth furnace/Bulk crystal growthMagnetic/Electrical properties measurement