Thin Film Solutions

01-2010

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Global Structure

14.09.2012 3

AMERICAS

Sales and Project Execution

EUROPE

HQ, R&D, Manufacturing Dresden GER Service Hub Erfurt GER

ASIA PACIFIC

Service Hub and SalesGreater China, South East Asia Taiwan

Trading Partners Japan, Korea

Thin-Film Solutions

• HiBarSens

• Special equipment for thin film deposition (excerpt…)– DEZn supply for ZnO TCO layers– TMAl supply for AlOx backside passivation– PECVD for barrier layers – HMDSO…– Enabling III/V on Si– Special liquid Indium-MO source

supply systems for IGZO– LED supply systems for MO-III (TMGa)– ….

14.09.2012 4

Water Vapor

Permeation

Measurement System

Food industry

Pharmaceutical industry

Anorganic solar cells

Organic solar cells

Vacuum isolation paneele

Organic LED

10-0

10-3

10-61E-6

1E-5

1E-4

1E-3

0,01

0,1

1

10

Wat

er tr

ansm

issi

on ra

te W

VTR

g[H

2O] m

-2d-

1

Summary: Starting point

currentlymeasurable

bystandardmethods

?

WVTR of 10x g m-2 d-1 is equivalent to:

10-7 10-6 10-5 10-4 10-3 10-2 10-1 100 101 102 103 104

… per day!

One water drop …… at a sample area of:

WVTR

???

Vatican City

Tennis court

Dresden Zwinger + park

Soccer fieldPing-pong table

Chessboard

Beer coaster

Crown cork

Confetti Industry standard (MOCON)

Market forecast for ultra barrier films

0

0.5

1

1.5

2

2.5

3

3.5

4Bi

llion

US$

Year

Photovoltaics

Electrophoretic*

OLED light*

OLED Billboard etc*

OLED display*

Harry Zervos: "Barrier Films for Flexible Electronics: Needs, Players &Opportunities". IDTechEx Ltd., December 2008)

HiBarSens

• HiBarSens Basics

BASICS

n Measuring setup: dynamic (isostatic) static (quasi isostatic)

n Typical chart

n Calculation of WVTR

Measuring modes: dynamic vs. static

ϕϕ−

⋅⋅⋅⋅⋅

=1

2 pATRMV

WVTRsample

OHPurge&

tp

AM

TRVnWVTR

sample

OHcellsorp ∆

∆⋅⋅⋅

⋅=−

ϕ2&

Sample 1

Sample 2

10-4

10-3

10-2

10-1

Wat

er v

apor

mas

s flu

x j

/ g

m-2

d-1

Time t / h

Wat

er v

apor

vol

ume

fract

ion

ϕ / p

pm

Time t / h

WVTR

WVTR

ϕ … Water vapor volume fraction (measured by LDS)

n Tunable diode laser absorption spectroscopy (TDLAS)

Limit of Detection LOD(H2O):

n Measuring setup:

n Sample size

n Chamber volume

n Accumulation time

n Purge flow

n Optical path length

n WVTR < 10-4 g m-2 d-1

are measurable

100 ppb m

The LASER as a sensor

100 cm2

0,1 l

- 10 h

0,01 slm -

1 m

~ 10-6 g m-2 d-1~ 10-5 g m-2 d-1

dynamic static

!Theoretical estimations!

Balance equation for dynamic

n = amount of substance (moisture)

n

cell

sample

Adsorption isotherm

Steady-state conditions

ϕϕ−

⋅⋅⋅⋅⋅

=1

2 pATRMV

WVTRSample

OHPurge&

nsorption@cell•

nsorption@sample•

nout•

Nadsorp

pH2O

10-4

10-3

10-2

10-1

Mas

s flu

x j H

2O /

g m

-2 d-1

Time t / h

Sample 1

Sample 2

General balance equation

Vpurge; nin• •

Calculation of WVTR

( ) .0

0

0

0

consttnnnnpp

nnn

outperm

adsorptiondesorptionsorption

=∆⋅−=−=−

=−=

&&

&&&

( ) ooutleaksorptpermin ntnnnnnn +∆⋅−+++= &&&&&

( ) ooutperm ntnnn +∆⋅−= &&

npermeation•

Balance equation for static setup

( ) osorptperm ntnnn +∆⋅+= &&

0;0

;0

0 >−>−=

===

ppnnnconstnnn

desorptionadsorptionsorption

permoutin

&&&

&&&

Adsorption isotherm

Nadsorp

pH2O

cell

sample

n = amount of substance (moisture)

nnsorption@cell•

npermeation•

nsorption@sample•

( ) ooutleaksorptpermin ntnnnnnn +∆⋅−+++= &&&&&

General balance equation

„non constant“ conditions

tp

AM

TRVWVTR

AM

tn

AM

nWVTR

Sample

OHcell

Sample

OH

Sample

OHperm

∆∆⋅

⋅⋅⋅

=

⋅∆∆

==

ϕ2

22&

tp

AM

TRVnWVTR

Sample

OHcellsorp ∆

∆⋅⋅⋅

⋅=−

ϕ2&

Calculation of WVTRnout•

nin•

Wat

er v

apor

vol

ume

fract

ion

ϕ / p

pm

Time t / h

00 24 48 72 96

0

1

2

3

4 GRA, Quasi-isostatisch_neu_GM_12_06_07, 4.7.2012

Time t / hh

Wat

er v

apor

vol

ume

frac

tion

ϕ /

ppm

Static measurement: Background level

purge quasi isostatic measurement

Measured background level (sample: stainless steel)

@ 38°C / 90% r.H.WVTRqis = 2,5 x 10-6 g m-2 d-1

00 24 48 72 96

0

1

2

3

4 GRA, Quasi-isostatisch_neu_GM_12_06_07, 4.7.2012

Time t / hh

Wat

er v

apor

vol

ume

frac

tion

ϕ /

ppm

Dynamic vs. Static: background level

Measured background level (sample: stainless steel) @ 38°C / 90% r. H.

WVTRqis = 2,5x 10-6 g m-2 d-1

Dynamic setup Static setup

010 020 030 040 050

10-5

10-4

10-3

10-2 SCHA, H2O_Konzmessung_Leermessung_isostatisch, 4.7.2012

Time t / DDD

Wat

er v

apor

mas

s vel

ocity

/ g

m-2 d

-1

WVTRqis = 5x 10-5 g m-2 d-1

PPRODUCTIMPLEMENTATION

HiBarSens

Sensitivity of a WVTR measurement

N2H2O

N2 + H2O

Sealing of the test cell

Sensor sensitivity

Adsorption / desorption of moisture

Parameters for tuning the sensitivity

LOD = 150 ppb mTheoretical sensitivity

N2H2O

N2 + H2O

dcIIo

⋅⋅=− λελλ

)()(ln

c

dynamic setup

• Optical path length• Carrier gas flow à c• Sample area à c• Selection of absorption line

Tuning sensitivity: optical path length

Multipath design in HiBarSens®

2 m optical path length by multi 20 reflections

Tuning sensitivity: Carrier gas flow

02 24 240

10-4

10-3

10-2

10-1

100

0

10

20

30

40

50

60

WVTR

Purg

e flo

w V

* / s

ccm

WVT

R /

g[H

2O] m

-2d-1

Time t / hours

Purge gas flow

Carrier gas flow 3 sccm - 50 sccm

Boost the sensitivity by factor 16!

Sensitivity of WVTR measurement

Sensor sensitivity: the laser as a sensor

n High dynamic range: ppb - % (10-5 – 1 g m-2 d-1)n Very high selectivityn Immune to high concentrated moisturen Long time stable, no drift, no hysteresisn Low-maintenancen Change of target permeate by change of the laser

dioden Allows the realization of a compact designn Easy to use

Further advantages

Tunable Diode Absorption Spectroscopy (TDLAS) is a non-invasive, high sensitive, high selective sensor for detection of moisture traces!

Sensitivity of WVTR measurement

Adsorption / desorption of moisture

N2H2O

N2 + H2O

10-4

10-3

10-2

10-1M

ass

flux

j H2O

/ g

m-2

d-1

Time t / h

jcell = jsample = jtubes = 0

jsystem = WVTR (δj/δt = 0)

Sample 1

Sample 2

Mass flux [ ][ ]dtmA

gmdm

gj

jjjWVTRj

x

OHx

tubessamplecellsystem

∆⋅

∆=

⋅

+++=

²][2

2

Sensitivity of WVTR measurement

Adsorption / desorption of moisture

N2H2O

N2 + H2O

n Steady state conditions are requiredn As small as possible surface area of the cell

in contact with moisturen Ultra smooth surfacesn Avoid any problematic materials inside the

celln Highest temperature stabilityn HiBarSens - realization n Volume and surface vs. sample area

optimized cell designn Electro-polished surfacesn Temperature stability < 0,5°Cn Sensor is placed inside the test cell

Sensitivity of WVTR measurement

Sealing of test (measuring) cell

n Sample clamping has to follow the requirement for leakage rates of 2.4E-9 mbar*l/sn Substitution of the classical concept

(polymer O-rings) by the concept of an “active sealing”

n Purge channels prevent ambient moisture diffusion into the cell

Mass flux: leakagecellsystem jjWVTRj +++= ...

HiBarSens® at work

0 10 20 30 40 5010-5

10-4

10-3

10-2

Time t / d

Mass f lux (H2O) / g m-2 d-1

5 x 10-5 g m-2 d-1

Measured background level

(sample: stainless steel)

00:00 24:00 48:00 72:00 96:00 120:00 144:00 168:0010-4

10-3

10-2

10-1 WVTR / g m-2 d-1

Time t / h

Adjusting the gas flow

4,1 x 10-4 g m-2 d-1

WVTR-measurement

of ultra barrier sample

(Fraunhofer POLO)

3,12 3,14 3,16 3,18 3,20 3,22 3,24 3,26 3,28 3,30

-8,4

-8,0

-7,6

-7,2

1000/Temperature / K-1

ln(WVTR / g m-2 d-1) (@ 85 % RH)

Temperature dependence of ultra barrier sample

(for photovoltaic)

Measurement

compact & easy to use device

Rel. Humidity controller

Sample

Flow controller

N2 purge gas in /out

Permeation cell- tempered- integrated moisture generator- Gentle clamping of

the test sample

Purifier valve

Place sample

Close test cell

Adjust rel. Humiditypurge flow, temperature

Print report

Connectors for thermostat

Summary

n HiBarSens laser based sensor technology for highly sensitive determination of water vapor transmission rates of ultra barrier samples

n HiBarSens provides reliable measurements of WVTR down to 10-5 g m-2 d-1 with the potential to 10-6 g m-2 d-1

n HiBarSens is available as a compact, easy to use table top device

Acknowlegment

Johannes Grübler

Kurt Pietsch

Harald Beese

Wulf Grählert

responsible for manufacturing and sales