Leiterplattenoberflächen im Fokus · For improved drop-test performance OSP is the most favourable surface ENEPIG was developed further and displays now a real „Universal Finish“

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Auswahl der besten technischen und kommerziellen Lösung für Ihre Anwendung

Leiterplattenoberflächen im Fokus

Hubert Haidinger

Director PE/CAM BU Industrial & Automotive

28. Februar 2013

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Major Decision drivers

Requirements for the PCB surfaceRequirements for the PCB surfaceRequirements for the PCB surfaceRequirements for the PCB surface

Application ?

Solderability ?

Wire Bond process ?

Mechanical Requirements

?

Cost?

Shelf Life ?Rework ?

Leiterplattenoberflächen im Fokus / Hubert Haidinger

AgendaAgendaAgendaAgenda

Leiterplattenoberflächen im Fokus / Hubert Haidinger 2

Requirements for the PCB SurfaceRequirements for the PCB SurfaceRequirements for the PCB SurfaceRequirements for the PCB Surface

Which surfaces are available ?Which surfaces are available ?Which surfaces are available ?Which surfaces are available ?

Environmental & Recycling Environmental & Recycling Environmental & Recycling Environmental & Recycling

Surface Recommendations from AT&SSurface Recommendations from AT&SSurface Recommendations from AT&SSurface Recommendations from AT&S

Cost of surfaces & Cost DriverCost of surfaces & Cost DriverCost of surfaces & Cost DriverCost of surfaces & Cost Driver

Widely used surface finish for all kinds of products

+Easy and „cheap“ process+Even surface+Very well known+Very robust solder joint

-More assembly issues due to LF requirements-Not suitable for wire bonding or contact pads-Inspection

Thickness: Thin ones (one solder step) 0,1µm; „normal ones“ 0,2µm to 0,5 µm

SurfaceSurfaceSurfaceSurface finish finish finish finish ---- OSPOSPOSPOSP

3Leiterplattenoberflächen im Fokus / Hubert Haidinger

Very common surface finish for automotive and industrial applications

+Very cheap and easy process+Very reliable+Very easy to solder+Shelf life+Less problems

-Uneven surface (thickness range from 1to 40 micrometer)-Thermal shock for PCB-Environmental issues (Lead Free)-Not suitable for small design and contact pads or wire bonding

Thickness: HAL on pad 1 – 40 µm, edge of holes should be covered

SurfaceSurfaceSurfaceSurface finish finish finish finish ---- HALHALHALHAL


More and more common surface finish for industrial and automotive applications (replacement for HAL)

+Very even surface+Good solderjoint reliability+Lead free+Easy to solder+Perfect for pin in or press fit

-Complex and expensive process-Aggressive chemistry (attacks soldermask)-Sensitive to contamination-Not suitable for contact pads

Thickness: 0,8 to 1,2 µm; For LF applications 1,0 to 1,4 µm is prevered)

SurfaceSurfaceSurfaceSurface finish finish finish finish –––– Immersion TinImmersion TinImmersion TinImmersion Tin


Used for industrial and automotive applications (North America)

+Very even surface+Easy process (compared to ENIG+Imm Tin)+Good solderjoint reliability+Easy to solder+Lead free+Not aggressive process+Suitable for wire bonding

-Risk of tarnishing (must be packed within short time)-Sensitive to sulfur-Not suitable for contact pads -Studies show that there is the risk of migration, especially in the precence of copper

Thickness: 0,15 to 0,4µm

SurfaceSurfaceSurfaceSurface finish finish finish finish –––– Immersion Immersion Immersion Immersion SilverSilverSilverSilver


Very popular surface finishing for all kinds of PCB (industrial, automotive, telecom application)

+Even surface+Reworkable (solderpaste misprinting)+Long storage time+„Easy“ to solder+Multi reflow approved+Can be used for wire bonding+For soldering and contact pads

-High process costs (Chemistry and long cycle time)-Process is very complex-Ni-Corrosion/Black pad-Risk of brittle solder joint (Too much Au in solder, P content,…)-For small BGAs solderjoint reliability is lower as on other surfaces

Thickness: Ni thickness normally 3 – 6 µm, Au thickness 0,05 to 0,12 µm

SurfaceSurfaceSurfaceSurface finish finish finish finish ---- ENIGENIGENIGENIG


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Available surfaces Available surfaces Available surfaces Available surfaces

Surface Soldering AL Wire Bondable Gold Wire Bondable M echanical Strength

OSP Yes No No Pure ( Copper )

Carbon No No NoHigh & Reliable ( new Ink types )

HAL SNPB Yes No No Pure

HAL Pb-free Yes No No Pure

Imm. Sn Yes No No Pure ( 1µm )

Imm. Au Yes Yes No Ok ( Low Gold Layer )

Imm.Ag Yes Yes Yes Pure

ENEPIG Yes Yes Yes OK ( Low Gold Layer )

Electrolytic Ni/Au

No Yes NoHigh Very Reliable ( Edge Connector )

Electrolytic Sn

Yes No No Pure

ElectrolyticSoft Gold

Yes ( but Risk ) Yes YesOk ( higher Layer of

Gold )

Immersion Soft Gold

Yes ( but Risk ) Yes YesOOk ( higher Layer of

Gold )









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80%

100%

120%

140%

160%

180%

200%

220%

240%

OSP HAL ( Lead Free ) Immersion Tin 1 µm ENIG ENEPIG ENIG + Plated Gold

Cost based on a 2 Layer PTH PCB with Format 160 mm x 100 mm 1,55 mm / 18 µm Copper








SurfaceEnergy

[kWh/m²]

Waterconsumption

[l/m²]Potential Risk Recycling

OSP 1 23 No significant Risk No

Imm. Ag 3 0,02No significant Risk Silver recycling

internal

HAL Pb-frei 5 19No significant Risk

Tin from the process is recycled and re-

used

Imm. Au 7 0,04Kaliumgoldcyanid � high Risk for the employee � high security and control Monitoring needed

Gold Bath and rinse water are external

recyled

Imm. Sn 11 63No significant Risk

No

ENEPIG 18 0,11Kaliumgoldcyanid � high Risk for the employee � high security and control Monitoring needed

Gold is recyledexternal

Galv. Ni/Au 68 146Kaliumgoldcyanid – same as Imm.Au

Nickelchlorid /-sulfat: Risk for cancer � High security needed and regular medical examination

Gold is recyledexternal

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Environmental & Recycling InformationEnvironmental & Recycling InformationEnvironmental & Recycling InformationEnvironmental & Recycling Information









Guideline Guideline Guideline Guideline forforforfor Industrial Industrial Industrial Industrial andandandand Automotive AreaAutomotive AreaAutomotive AreaAutomotive Area

Immersion Tin displays a very good choice for manyapplications in Industrial and Automotive

ENIG is loosing Ground to Cost reasons

For improved drop-test performance OSP is the mostfavourable surface

ENEPIG was developed further and displays now a real „Universal Finish“ that fulfills also the demand for „no bondfailures“.


HoweverHoweverHoweverHowever youryouryouryour thethethethe needsneedsneedsneeds ofofofof youryouryouryour specificspecificspecificspecificapplicationapplicationapplicationapplication definesdefinesdefinesdefines thethethethe rightrightrightright surfacesurfacesurfacesurface …………

Surface Pros Cons

OSP

Organic Surface Preservative

Cheap, good joint integrity, easy to apply

Poor solder wetability

No testing through OSP possible

ENIG

Electroless Nickel Immersion Gold

Best Solder ability, good joint integrity, multiple reflow possible

Cost intensive, failure black-pads

Poor resistivity against SO2

ENEPIG

Electroless Nickel Electroless Palladium Immersion Gold

Similar to ENIG, additional feature: bonding is possible

Cost intensive, failure black-pads

Poor resistivity against SO2

Silver Simple application, multiple application possible, „mixed finishes“ possible

Mid range solder ability, poor joint integrity, risk of silver voids

Tin Good solder joint, good prize Mid range joint integrity, discoloration, no multiple reflow possible


AT&S – Well Positioned for the Future

Documents

Leiterplattenoberflächen im Fokus · For improved drop-test performance OSP is the most favourable surface ENEPIG was developed further and displays now a real „Universal Finish“