30
P B P B T T Nanometrology Nanometrology requirements requirements Overview Overview of of instrumentation instrumentation at PTB at PTB - - Optical Optical mask mask comparator comparator - - Electron Electron - - optical optical metrology metrology system system - - New 1D New 1D vacuum vacuum nm nm - - comparator comparator - - Angle Angle comparator comparator International International comparison comparison Nano3 Nano3 Future Future needs needs H. Bosse, PTB, Department 5.2 H. Bosse, PTB, Department 5.2 for for length length and angle and angle graduations graduations NIST, NIST, Gaithersburg Gaithersburg , , January January 27 27 - - 29, 2004 29, 2004

NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

  • Upload
    others

  • View
    7

  • Download
    0

Embed Size (px)

Citation preview

Page 1: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT������������������������������

•• NanometrologyNanometrology requirementsrequirements

•• OverviewOverview of of instrumentationinstrumentation at PTBat PTB-- OpticalOptical maskmask comparatorcomparator-- ElectronElectron --opticaloptical metrologymetrology systemsystem-- New 1D New 1D vacuumvacuum nmnm --comparatorcomparator-- Angle Angle comparatorcomparator

•• International International comparisoncomparison Nano3Nano3

•• Future Future needsneeds

H. Bosse, PTB, Department 5.2 H. Bosse, PTB, Department 5.2 forfor lengthlength and angle and angle graduationsgraduations

NIST, NIST, GaithersburgGaithersburg , , JanuaryJanuary 2727--29, 200429, 2004

Page 2: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT ���������� ���������������������������� ������������������������ ������ ������ ����������������������

DrivingDriving Technologies:Technologies:

-- SemiconductorSemiconductor productionproduction ((OverlayOverlay, , featurefeature placementplacement, CD, ...), CD, ...)

-- CD/DVD disc CD/DVD disc masteringmastering processprocess (linear (linear positionposition controlcontrol))

-- ProductionProduction of material of material measuresmeasures of of lengthlength and and lengthlength measuringmeasuring systemssystems

-- UltraprecisionUltraprecision machiningmachining

-- NanotechnologyNanotechnology, , nanostandardsnanostandards

-- ......

RequirementsRequirements::

-- ProvideProvide lengthlength and and xyxy--coordinatecoordinate valuesvalues traceabletraceable to SI to SI unitunit of of lengthlength

-- DetermineDetermine deviationsdeviations fromfrom 1D1D--linearity linearity oror 2D nominal 2D nominal patternpattern positionspositions

Page 3: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT ���������� ���������������������������� ������������������������������������������ ���������������������� ������ ������������ ��������������������

PrerequisitesPrerequisites::

-- DisplacmentDisplacment measurementsmeasurements directlydirectly traceabletraceable to to thethe SI SI metermeter definitiondefinition

-- Position Position controlcontrol systemssystems forfor compansationcompansation of residual of residual guidingguiding deviationsdeviations

-- ApplicationApplication of of errorerror separationseparation methodsmethods to to determinedetermine residual residual deviationsdeviations

-- High High precisionprecision material material parameterparameter characterizationcharacterization: :

compressibilitycompressibility, thermal , thermal expansionexpansion

-- DevelopmentDevelopment of of modelmodel to to describedescribe probeprobe--samplesample interactioninteraction

-- ClearClear definitiondefinition of of measurandmeasurand

-- UncertaintyUncertainty budgetbudget accordingaccording to GUMto GUM

Page 4: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT� ������ ����� ���!�"����!�"����������������������������� ������ ������������ ��#��������#������

-- OpticalOptical maskmask comparatorcomparator

-- ElectronElectron --opticaloptical metrologymetrology systemsystem

-- 1D 1D vacuumvacuum Nanometer Nanometer comparatorcomparator

-- Angle Angle comparatorcomparator

Page 5: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT!�������!������������������������� ������������������ ��������

Current LMS 2020 performance for 2D coordinate metrology:- Repeatability in one orientation: 4 nm (3s)- Agreement of grid coordinates with mask measured in

different orientations: < 10 nm

PrinciplePrinciple TechnicalTechnical realizationrealization

Pattern placementcalibrations offered

to mask industrysince 1990

Page 6: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT$���%&%&��$���%&%&���������'������������'����� ����������#���������#����� ��������������������

Results for Cr/quartz-photomask:

� 7´´ (178 mm) mask size

� (15 x 15) grid, 5 mm pitch

� 16 repeat measurements

� Differences from mean coordinates

� Statistics of observed differences:

x / nm y / nmmaximum 4,1 6,1minimum -4,7 -4,7mean 0,0 0,0std. dev. (3 s) 3,6 3,6

Page 7: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT���� ������������������ ��������������������������������������������������������

CoordinateCoordinate system system withwith „„ errorserrors ““

0 °0 ° 90 °90 °

180 °180 ° 270 °270 °

4 4 orientationorientation methodmethod ::eliminationelimination of of instrumentinstrument deviationsdeviations

byby variationvariation of of phasephase of of signalssignals

ResultResult

butbut: : completecomplete errorerrorseparationseparation also also

needsneeds translationtranslation !!

Page 8: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT$���%&%&��($���%&%&��())�������������������������������������������� ��������������������

Results for Cr/quartz-photomask:

� 7´´ (178 mm) mask size

� (15 x 15) grid, 5 mm pitch

� 4 orientations

� Differences from mean coordinates

� Statistics of observed differences:

x / nm y / nmmaximum 6,3 6,7minimum -6,2 -6,5mean 0,0 0,0std. dev. (3 s) 5,3 5,4

Page 9: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT�*������*���������������������))*������*������ ������������������ ����������

PropertiesProperties ::

-- VacuumVacuum interferometryinterferometry forfordisplacementdisplacement measurementmeasurement

-- 300 mm 300 mm rangerange of xof x --y y stagestage

-- High High resolutionresolution lowlow voltagevoltageee--beambeam probe probe (5(5--10 nm)10 nm)

Page 10: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT�*�����*���������������������� #����+�#����+������� ���,���,

XY-stage

vacuum chamber

Y-interferometer

reference-mirror

20 cm

X-inter-ferometer

autocollimator

plane mirrorH

eNe-

lase

rSEM

Page 11: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT�*�����*���������#���'����������#���'����� ���������#���# ��������������������

Results for Cr/quartz-photomask:

� Stuctures with 1 µm CD, 6´´ (150 mm) mask size

� (13 x 13) grid, 10 mm pitch

� 15 repeat measurements

� Differences from mean coordinates

� Statistics of observed differences:

x / µm y / µmmaximum 0,008 0,008minimum -0,006 -0,010mean 0,000 0,000std. dev. (3 s) 0,005 0,007

20 nm

Column

Row

Page 12: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT�*�����*���������#��������#��� ���������������� -��.��#���-��.��#�����������������

ContributionsContributions to SE edge to SE edge contrastcontrast ??slopeslopecontrastcontrast

diffusiondiffusion

backback--scatterscatter

beambeamprofileprofile

400 420 440 460 480 500 520 540 560 580 600-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

200

nm

Surface Topography

Sidewall slope: 90° 87° 85° 83°

Fit-Function ex

Sig

nal

[arb

. Uni

ts]

Scan Position [nm]

Monte Carlo Monte Carlo basedbasedsimulationsimulation of edge of edge signalssignalsexampleexample: : influenceinfluence of edge of edge slopeslope

Page 13: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT/ �/ ���������������������������))����������������+�01��2�����+�01��2�����������������������

1,900 µm

3,722 µm

500 nm

0 500 nm

I

II

A B C

I II I II I II

EOMS 213 176 293 276 967 964

VERITECT 205 180 281 270 960 961

Measured CD values in nm, compared at top edge positions, differences < 15 nm

VERITECT (AFM) EOMS (LVSEM)

Si: h = 480 nm, DUV-lithography, dry etched

1,900 µm

3,722 µm

Page 14: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT$3$3))������#�43�������#�43���������������������������������5����/ �����5����/ ���������

-70

-60

-50

-40

-30

-20

-10

0 200 400 600 800 1000 1200 1400

CD

: D

evia

tio

n f

rom

no

min

al [

nm

]

Nominal CD [nm]

CD instrumentation:LV-SEM, top CD:-

18.1020.1008.11

- UV microscopy

Mean offset: 33 nm

2,500 µm

100 nm

0

Profil

AFM: Edge angle: ≈≈≈≈ 74°

Expected difference betweentopCD and CD at 50% on edge at ARCr layer of 100nm: 30 nm

Isolated opaque lines

AFM characterization

Page 15: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT��������������������������������������������*'6������*'6������

•• New PTB standard length comparatorNew PTB standard length comparator

•• Smallest uncertainties achievable by vacuum Smallest uncertainties achievable by vacuum interferometryinterferometry

•• Measurement range: up to 610 mmMeasurement range: up to 610 mm

•• Length calibrations and comparison measurements uncertainty goalLength calibrations and comparison measurements uncertainty goalss

•• Line scaleLine scale UUaimaim ≤≤ 5 nm5 nm (single line detection)(single line detection)

•• Length on photo maskLength on photo mask UUaimaim ≤≤ 5 nm5 nm

•• Linear encoderLinear encoder UUaimaim ≤≤ 3 nm3 nm (multiple line detection)(multiple line detection)

•• Laser interferometerLaser interferometer UUaimaim ≤≤ 2 nm2 nm

•• Larger 2DLarger 2D--objects with width up to 450 mm measurableobjects with width up to 450 mm measurable

Page 16: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT��������������������/���������/�������������!��������!��������

Interferometer Beamsplitter

Granite VibrationIsolation

Bellow

Bellow Slide Bridge

Microscope

Scale

Measurement Slide

LinearDrives

Page 17: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT��������������������/���������/����������������������������������������� ������������������

scale

microscope

interferometerbeam splitter

measurement slide

movingmirror

fixedmirrors

•• Compensation of thermal dilatation and bending Compensation of thermal dilatation and bending

•• Interferometer arrangement as virtual measurement frameInterferometer arrangement as virtual measurement frame

Page 18: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT��������������������/���������/�������������7�����#���7�����#��� ����������������������������

AOMMeasurement

ReferenceLaser

Fibers

Bellow

Beamsplitter

Polarizers

TubesVacuum Chamber

Window

Nd:YAG, 532 nm

Page 19: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT��������������������/���������/�������������*������,*������,

InterferoInterfero--metermeter

MicroscopeMicroscopeunitunit

CarriageCarriage

DriveDrive

InstalledInstalledat PTB:at PTB:

Sep. 2000Sep. 2000

Page 20: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT��������������������/���������/����������������������������������������� ����������

Page 21: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT��������������������/���������/��������������������������������� ����������������������

filter inlet

filter inlet

cabin

measurement room

electrical heating

floor

control room

comparator

shielding

ground isolation

Abbe-Building

Surface

2 m

9 m

Cabin Control

room

Measure-mentroom

Groundisolation

Electricalheating

Page 22: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT!�"�0�����!�"�0�������������������������

•• RealizationRealization of angle of angle withwith resolutionresolution of 0.001´´ and of 0.001´´ and uncertaintyuncertainty of 0.005´´of 0.005´´

•• CalibrationCalibration of of devicesdevices and and standardsstandards overover 360° angle and 360° angle and smallsmall anglesangles

•• ExampleExample : : CalibratedCalibrated autocollimatorsautocollimators (U = 0.007´´)(U = 0.007´´) appliedapplied forfor topographytopographymeasurementsmeasurements byby angle angle deflectometrydeflectometry withwith subsub --nmnm uncunc . . (PTB, (PTB, sectionsection 4.21)4.21)

Page 23: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT����8������������������������������8��������������������������������������������

•• 14 14 participantsparticipants fromfrom 4 regional 4 regional metrologymetrology organizationsorganizations

•• DurationDuration : 2000: 2000--20032003

•• 2 line 2 line scalescale transfertransfer standardsstandards manufacturedmanufactured byby HEIDENHAINHEIDENHAIN

•• ZerodurZerodur and and quartzquartz substratesubstrate materialmaterial

•• CharacterizationsCharacterizations of of substratesubstrate : thermal : thermal expansionexpansion , , compressibilitycompressibility

Layout:Layout:

Page 24: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT7����7�������������������� �'������'����� ����������������������������9���������������9�����

RelaxationRelaxation effectseffects havehave to to bebe takentakenintointo accountaccount at at thethe nmnm--levellevel !!

((herehere observedobserved on a 280 mm on a 280 mm glassglass ceramicceramic))

Page 25: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT$���%&%&��$���%&%&���������������������� ������������������������

Scales of Nano3 design are larger (280 mm) than LMS measurement range:

=> measurements in two overlapping, reversed positions necessary

0

2

4

6

8

10

12

14

-100 -50 0 50 100 S

tand

ard

Dev

iatio

n (2

s) [

nm]

Line Scale [mm]

NANO 3 Line Scale 683

0 deg180 deg

Position deviations from linearity Characterization of line edge qualityover 100 µm section of lines asmeasured in stripes of 12.5 µm

-25

-20

-15

-10

-5

0

5

10

15

20

25

-100 -50 0 50 100

Dev

iatio

n fr

om D

esig

n [n

m]

Line Scale [mm]

NANO 3 Line Scale 683

0 deg180 deg

Dev

iatio

n fr

omlin

earit

y[n

m]

Page 26: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTTDeviationsDeviations fromfrom weightedweighted meanmean valuevalue: : notenote slopeslope differencesdifferences

���������� ���%:&�������%:&������������ ���#���������#���������� �� )) ��������

Nano3, Measurand 1B, Quartz, deviations from weight ed mean

-100

-80

-60

-40

-20

0

20

40

60

80

100

0 40 80 120 160 200 240 280Nominal position / mm

Dev

iatio

n / n

m

PTB, LMS

B

C

D

E

F

G

H

I

J

K

PTB, nmK

Page 27: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT���������� ���%:&�������%:&������������ ���#���������#���������������������������� #��#��55

ComparisonComparison withwith weightedweighted meanmean afterafter eliminationelimination of of slopeslope differencesdifferences

Nano3, Measurand 1B, Quartz, linearity deviations, U < 20 nm

-16

-12

-8

-4

0

4

8

12

16

0 40 80 120 160 200 240 280Nominal Position / mm

Dev

iatio

n / n

m

PTB, LMS

B

C

F

I

mean

PTB, nmK

Page 28: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT

LMS 2020 Multilateration EOMS Nanometercomparator*

Measurand x-y-coordinates

x-y-coordinates

x-y-coordinates

Length

Uncertainty(k=2)

[(10 nm)² +(0,2 L)²]1/2

[(0,5 µm)² +(0,8 L)²]1/2

[(15 nm)² +(0,08 L)²]1/2

[(4 nm)² +(0,003 L)²]1/2

Meas. range 200 mm 700 mm 300 mm 610 mm

�������������������������������������������� ������������ ��#���#� � �))������������������

Page 29: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT1������1���������#���#;;

ShortShort--term needs:term needs:

-- Improvement of probe sample interaction modelling, refinement oImprovement of probe sample interaction modelling, refinement o f models byf models bymeasurements with improved reproducibility on bette r defined rmeasurements with improved reproducibility on bette r defined r eferenceeferencesamples with better known material parameterssamples with better known material parameters

-- Closer cooperation with highCloser cooperation with high --end manufacturing sites to jointly develop betterend manufacturing sites to jointly develop betterstandards which then can be calibrated with smaller uncertaintstandards which then can be calibrated with smaller uncertaint iesies

-- Improvement of cross calibration procedures between different mImprovement of cross calibration procedures between different m etrologyetrologyinstrumentationinstrumentation

-- Further evaluate the potential of (microFurther evaluate the potential of (micro --) ) scatterometryscatterometry methods for inmethods for in --linelineproduction monitoring, comparison with other high r esolution mproduction monitoring, comparison with other high r esolution m icroscopyicroscopy

-- Improvements of high quality graduations (profile l ine shape, sImprovements of high quality graduations (profile l ine shape, s maller pitches)maller pitches)

-- Improvement of AFM measurement speedImprovement of AFM measurement speed

-- MeasurandsMeasurands to take into account 3D shape of isolated or groupe d structuresto take into account 3D shape of isolated or groupe d structures

Page 30: NIST NNI Jan04 Bosse - WTEC: What's Ne · P BT •Nanometrology requirements •Overview of instrumentation at PTB-Optical mask comparator-Electron -optical metrology system-New 1D

P BP BTT1������1���������#���#;;

Mid and longMid and long--term needs:term needs:

-- Combination of different probing systems in one ins trument to iCombination of different probing systems in one ins trument to i mprovemprovedirect comparability of measurement resultsdirect comparability of measurement results

-- Combination of stable selfCombination of stable self --assembled structures (locally perfect) withassembled structures (locally perfect) with

globally defined high quality graduationsglobally defined high quality graduations

-- Increase potential of XIncrease potential of X --ray ray interferometryinterferometry for dimensional metrology (speed!)for dimensional metrology (speed!)

-- Increase potential of redundant measurement techniq ues in high Increase potential of redundant measurement techniq ues in high precisionprecisiondimensional dimensional nanometrologynanometrology (like e.g. (like e.g. trilaterationtrilateration , error separation), error separation)

-- Search for and investigate Search for and investigate newnew measurement principles and approaches measurement principles and approaches