deadly condensation â€“ reliability tests of electronic components

Deadly Condensation –Reliability Tests of Electronic Components by Micro Sensors

Tödliche Kondensation–Zuverlässigkeitstests mit Mikrosensoren

A.Steinke*, B.March*

2

Workshop Mikrosystemtechnik und Mikroelektronik in Sachsen und Thüringen, Zwickau, 14.Mai 2009

Summary

0 Introduction

1 Dangerous of Condensation

2 Reliability relevant Challenges

3 Micro Condensation Sensor

4 Field Tests and Results

Deadly Condensation –Reliability Tests of Electronic Components by Micro Sensors

3


CiS Forschungsinstitut für Mikrosensorik und Photovoltaik Erfurt

0 Introduction

4


0

0.1

0.2

0.3

0.4

0.5

0.6

300 400 500 600 700 800 900

Res

pons

ivity

in A

/W

wavelenght in nm

rev. bias=10mV - blue

rev. bias=5V - green

rev. bias=20V - red

Simulation and design

Design

Silicon-Waferprocessing

Device characterizationand Calibration

Assembly

ASIC

ASIC

ASIC

Modulare Components

Batch process based technological platforms - solution for product innovation

0 Introduction

5


SiMonitor diodeLEDsGlass ceramicmedium

Messobjekt

pin-diode

Example for microoptoelectronical Sensor-Platform

Pulse Oximetry

Microfluidic Lab-on-ChipFluorescence

Si-Chip

Heptan-Füllung

Gasblase

Libellen-Glas

Inclination

Turbidity

0 Introduction

6


0

0.1

0.2

0.3

0.4

0.5

0.6

300 400 500 600 700 800 900

Res

pons

ivity

in A

/W

wavelenght in nm



rev. bias=20V - red


Design



Assembly

ASIC

ASIC

ASIC

Modulare Components

Batch process based technological platforms - - solution for product innovation

0 Introduction

7


0.000

200.0

[µm]

495.0

[µm]

-275.00

-293.75

-312.50

-331.25

-350.00

[µm]

SiO2+Passivierung

n-- Epitaxie-Layer

Silizium n- Substrat

n+

AlSi

p+ n+

AlSi

p+

ExampleExample forfor PiezoresistivePiezoresistive PlatformPlatform

PressurePressure HumidityHumidity

bimorphbimorph

pHpH

HydrogeleHydrogele

MembraneMembrane CantileverCantilever

0 Introduction

8


0

0.1

0.2

0.3

0.4

0.5

0.6

300 400 500 600 700 800 900

Res

pons

ivity

in A

/W

wavelenght in nm



rev. bias=20V - red


Design



Assembly

ASIC

ASIC

ASIC

Modulare Components

Batch process based technological platforms - - solution for product innovation

0 Introduction

9


Product Developments based on CCC*-Sensor

ApplicationMeasurement of Dew Point of Concrete and Masonry/Brickwork

ApplicationMeasuring System forhigh Humidity Range (>95%)

ApplicationEnergy optimized HumidityControl in Air Conditioners byDew Point Measurement

ApplicationMeasuring System forRelative Humidity <5% and Mixing Ratio of 2...4g/kg

ApplicationMeasurement of Conden-sation on Electronic PrintedBoards

ApplicationAvoiding of Condensationon Chilled Beam, Glas,...

Example for Impedimetric Platform

0 Introduction

10



Complexity of sensors and electronics Trends in assembly and packaging

New riskfor long term stability of electronic components

Source: SIEMENS, SENSOR 2005, I&M Workshop

Miniaturization of lines and spacesMiniaturization of pitch widthIncreasing complexity of devicesMultilayer and microvia technologyAlternative solder paste alloys and substrate materialsNon-protection of PCB ???!!!!

Trends in electronic circuits

High resistivityHigh density on electronic devices……

11



Source:ADACmotorwelt 5/2008

Source: ADAC motorwelt 5/2009

Pannenstatistik 2008

12



Courtesy: ESPEC Corp.

Material factor 2PCB

Material factor 4Solder

Material factor 5Package

Materialfactor 1PlatingDew condensation

Material factor 3Flux

Environmental factor 3

MoistureEnvironmental factor 2

Environmental factor 1 Stress voltage

13


With condensation new riskfor long term stability of electronic components

accelerated by

>potential difference>field strength>Insufficient isolation (temporary)


Corrosion of • surface• conductive tracks• chip metallization

but since

dew condensat in combination with contamination

14


Corrosion on the top of the PCB

after 5 dewing cycles

after 15 dewing cycles

Failures caused by Dewing Tests

Courtesy:BMW AG


15


Failures caused by Dewing Tests


Courtesy:FABS Erlangen

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Environmental climate tests in test chambers e.g.

>temperature and humidity cycle tests>constant high humidity tests>low/high temperature tests>water resistant tests>salt water spray tests

Failure in electronic boards

Typical diagnosis:

KFG „Kein Fehler gefunden“ (now failure found)

Methods are necessary to reduce qualification efforts+

Improve the quality of electronic components by early failure recognition

TCTPCTMCTHHTHTS

17



JASO D 001JASO D 001--94:94:

TemperatureTemperature chamberchamber --5 5 ±± 22°°CC 2 2 ±± 0,5h0,5h

ClimateClimate test test chamberchamber 35 35 ±± 22°°CC 85 85 ±± 5%rF5%rF 10min10min

Temperaturen Temperaturen rampramp (BMW):(BMW):

ClimateClimate test test chamberchamber 10......7010......70°°CC 98....100%rF98....100%rF 3,5h3,5h

IEC 60068IEC 60068--22--30:30:

ClimateClimate test test chamberchamber 25......8025......80°°CC 95....100%rF95....100%rF 5h5h

ISO/DIS 16750ISO/DIS 16750--3 Test 3:3 Test 3:

Basis: IEC 60068Basis: IEC 60068--22--3030

ClimateClimate-- Simulation Simulation forfor DewingDewing TestTest

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Dewing on basisISO/DIS 16750-4

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+25

Relative hum

idity%

RH

100

90

80

70

60

Start of temperaturefall

End of temperaturerise

Time

+28

+22

5 h1 cycle

50 ½ h

100

95

DryingCondensation

½ h

3/41 ½

3/42

½ h

3/4

½ h

½ h

+82

*78

Dewing on basisIEC 60068-2-30

Source: FAKRA

coolingelement

Sensor area incl.- detection system- transducer

integrated signal processor

heat sinkmounting plate

sensor- environment

controller

interface

4 - 20 mA

Direct Measurement:Temperature PCBDew Point Temperature

20


But the main question is:

• Did or does a dew condensation take place ?

• What quantity of dew condensation has accumulated?

• How long does the state of the dew condensation last?


To answer these questions you have

> to measure the quantity of water condensation at different positions in a vehicle

>to reproduce dew condensation at the same level in a climate test chamber

21



Necessary features of the micro sensor:

⇒miniaturized suitable for assembly at different placesin the vehicle

⇒ low thermal mass for short respond

⇒ low power consumption to avoid thermic cross sensitivity

⇒ high reproducibility of the measured parameter

⇒ long term stability e.g. high chemical resistance to acid,alkaline, solvents

⇒ easy to calibrate

⇒ parameter to measure temperature of air and close to the surfacerelative humidity of air, on top of PCBquantity of condensation (water mass)

22


CCC-Sensor, Modelling & Design

CCC- condensate controlled capacitance according HEINZE

SPICE model of stray field capacityDesign of IDE with different line to line space

3 Advanced Micro Condensation Sensor

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0 5 10 15 20 25 30 35 40

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

Output signal of the sensor assembly as a function of the amount of water

freq

uenc

y [H

z]

amount of water (average) [µg/mm^2]

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The smart system of the condensation sensor

Detectioncomponents

Transducercomponents

Signal-pre-processing

Signalprocessing

Calibrationprogram

Interface

Condensation IDE C/f-converter Linearization Adjusting Output signal


25



CourtesyCourtesy: BMW AG: BMW AG

behind the combi instrument

behind the board monitor

within the car climate

under the roof

behind the GPS

within the Audio Box

test result inside the car:max. water mass 12...16µg/mm2

4.14.1 Tests at different Tests at different partsparts of of thethe carcar

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Workshop Mikrosystemtechnik und Mikroelektronik in Sachsen und Thüringen, Zwickau, 14.Mai 2009 CourtesyCourtesy: OPEL: OPEL

test result inside the car: 15µg/mm2


Tests at different Tests at different partsparts of of thethe carcar

27

Workshop Mikrosystemtechnik und Mikroelektronik in Sachsen und Thüringen, Zwickau, 14.Mai 2009 21.07.2006 Quelle: FAKRA/DELPHIQuelle: FAKRA/DELPHI


4.24.2 Tests in Tests in thethe climateclimate test test chamberchamber

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Workshop Mikrosystemtechnik und Mikroelektronik in Sachsen und Thüringen, Zwickau, 14.Mai 2009 21.07.2006 CourtesyCourtesy: FEUTRON: FEUTRON



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Challenge: Realization of 0-20µg/mm2 between 10° and 70°C

BMW GS 95011-4

0

20

40

60

80

100

120

Zeit 14h

Tem

pera

tur [

*C] /

rel.

Feuc

hte

[%]

% rel. Feuchte: soll% rel. Feuchte: ist*C Betauen: soll*C Betauen: ist

*C Temperatur: soll*C Temperatur: ist

0

5

10

15

µg/m

m²

IEC 60068-2-30

0

20

40

60

80

100

120

Zeit 10 h

Tem

pera

tur [

*C] /

rel.

Feuc

hte

[%]

rel. Feuchte: sollrel. Feuchte: istTemperatur: sollTemperatur: ist

0

5

10

15

µg/m

m²

SourceSource: FAKRA/BMW: FAKRA/BMW



30

Workshop Mikrosystemtechnik und Mikroelektronik in Sachsen und Thüringen, Zwickau, 14.Mai 2009 Courtesy:FABS Erlangen

4.3 Test Pattern

Design of TestboardComb pattern (line space 0,2 mm,0,3 mm, 0,4 mm)Online data acquisition of current (comb pattern)Ceramic capacitors (optical analysis)Adjustment of thermal behavior by metal plates

Influencing factors Cleaning of boards according toIPC TM-650Surface metallization: pure copper andtin-platedTest voltage: 7 V and 10 VFull factorial design of experiments:2³ = 8 Alternatives and 3 line spaces


31

Workshop Mikrosystemtechnik und Mikroelektronik in Sachsen und Thüringen, Zwickau, 14.Mai 2009 Courtesy: FABS Erlangen

0

10

20

30

40

50

60

µA

80

Cur

rent

0 2 4 6 8 10 12 14 16 18 20 h 240

2

4

6

8

10

12

µg/mm²

16

Time

Con

dens

atio

n

Online-Measurement of Comb Pattern

CurrentSignificant increase of current caused by CondensationContinuous raise of standby currentEvaluation criteria: maximum of current during test period


32

Workshop Mikrosystemtechnik und Mikroelektronik in Sachsen und Thüringen, Zwickau, 14.Mai 2009 Courtesy: FABS Erlangen

0

5

10

15

20

25

30

µA

40

Cur

rent

Ste

p

0 2 4 6 8 10 12 14 16 18 20 h 240

2

4

6

8

10

12

µg/mm²

16

Time

Con

dens

atio

n

Online-Measurement of Comb Pattern

Current StepDetection of short-cuts caused by dendritsCorrelation with phases of condensationEvaluation criteria: first step of current > 10 µA


4.3 Test Pattern

33


Conclusion

> first time quantitative measurement of condensat mass

> calibrated output signal of water mass

> suitable for field measurement

> support for R&D and production of high integrated PCBs

34


Thanks for your attention!

deadly condensation â€“ reliability tests of electronic components

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