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Pb-Free
Program
- What is a "Pb-free product"?
- Why Pb-free?
- What about Automotive applications?
- Do austriamicrosystems
AG offer Green Products?
- Why is austriamicrosystems
AG always using "Pb-free" instead of lead free?
- When will Pb-free products
be available?
- Who is the Contact Partner?
- Are Quality & Reliability
Standards for Pb-Free packages different from
the standards for existing packages?
- Does "Pb-free" affect
the product reliability?
- What material will be
used for lead-finish plating?
- What material will be
used for BGA solder balls?
- What about the Whisker
phenomena on Tin?
- Why are there no problems
with Whiskers on laminate (BGA) devices?
- What does MSL mean and
why is it so important?
- How are the new MSL-classifications
done?
- Is a Pb containing component
compatible with a Pb-free solder paste?
- Is a Pb-free component
compatible with SnPb solder paste?
- Which changes will be
necessary in customer processes when using Pb-Free
components?
- What is the marking convention
for Pb-free devices?
- Is there a possibility
to recognize Pb-free parts in their reels, trays
or boxes?
- Does austriamicrosystems
AG choice of molding compounds contain inorganic
Phosphorus?
Answers
Pb-Free Program
1. What is a "Pb-free product"?
austriamicrosystems AG’s Pb-free products
are RoHS compliant. (EU – Directive 2002/95/EG)
This means mainly Pb will be replaced (less
than 0.1% lead in any base material) at the
lead finish or solder balls and the molding
compound or substrate materials do not contain
Polybrominated biphenyl (PBB) or Polybrominated
diphenyl ether (PBDE) either. Of Course, Mercury
(Hg), cadmium (Cd) and hexavalent chromium (Cr
6) are not contained in our products.
2. Why Pb-free?
On 27.01.2003 the European Parliament and the
council adopted the Directive 2002/95/EG (RoHS):
EU - Directive on the Restriction of the Use
of Certain Hazardous Substances in Electrical
and Electronic Equipment
(http://europa.eu.int/eur-lex/pri/en/oj/dat/2003/l_037/l_03720030213en00190023.pdf)
This directive bans the use of lead (Pb), mercury
(Hg), cadmium (Cd) and hexavalent chromium (Cr
6) in solders, and the use of Polybrominated
biphenyl (PBB), Polybrominated diphenyl ether
(PBDE) in substrate materials or mold compounds
for equipment put in circulation in the EU after
1. July 2006.
Although there is no similar rigorous legislation
in the US or Japan different US and Japanese
companies have already started to reduce or
ban Pb (and other substances).
The parts actually delivered by austriamicrosystems
AG are already free of Hg, Cd, Cr 6, PBB and
PBDE. Pb is part of the lead-finish.
Therefore austriamicrosystems AG has implemented
a Pb-free/RoHS compliance program. Part of this
program is the re-qualification of all packages
to ensure the same quality and reliability level.
These qualifications will be finished by the
end of 2004.
3. What about Automotive applications?
For the Automotive industry the "Directive
2000/53/EC of the European Parliament and of
the Council of 18 September 2000 on end-of life
vehicles" is valid. There is an exception
for lead as part of the solder but nevertheless
the lead finish for these parts should be changed
to Pb-free too.
http://europa.eu.int/eur-lex/pri/en/oj/dat/2003/l_037/l_03720030213en00240038.pdf
http://europa.eu.int/eur-lex/pri/en/oj/dat/2002/l_170/l_17020020629en00810084.pdf
4. Do austriamicrosystems AG
offer Green Products?
The expression "Green" is not really
defined yet - different customers and suppliers
have different interpretations on this, some
understand it just as Pb-free, some as RoHS
compliant.
What austriamicrosystems AG offers is a product
compliant to the RoHS directive.
If you have more restrictions as those defined
in the RoHS please contact us. We will check
if we can offer you an appropriate material
set.
5. Why is austriamicrosystems
AG always using "Pb-free" instead of lead free?
austriamicrosystems AG decided internally to
use "Pb-free" instead of "lead-free"
and "Pb" instead of "lead"
due to the possible misunderstanding of lead
(Pb) and lead (as in lead frame).
6. When will Pb-free products
be available?
All qualifications will be finished by end
of 2004. For details please refer to the "package
roadmap".
We recommend to start new projects as Pb-free
only. Please contact your sales and marketing
partner in order to discuss the specific project.
For switching over for a existing product (ASICs)
please contact your sales or customer service
contact.
http://www.austriamicrosystems.com/05foundry/pdfs/Package_Roadmap_v2_0.pdf
7. Who is the Contact Partner?
The Overall Project Leader is Mrs. Evelyn Brandlhofer,
please contact her at
pb-free@austriamicrosystems.com.
She will directly answer your question or establish
a contact for specific requests. Product specific
questions should be addressed to the specific
marketing and sales partner.
8. Are Quality & Reliability
Standards for Pb-Free packages different from
the standards for existing packages?
No. Quality and Reliability Standards remain
the same.
Please notice that the MSL classification has
to be adopted to the new (higher temperature)
soldering profiles (see JEDEC J-STD-020C).
9. Does "Pb-free" affect the
product reliability?
Pb-free Products are designed and qualified
for the same or better performance as today
(with respect to the higher temperatures required
for the Pb-free board assembly process).
10. What material will be used
for lead-finish plating?
100% Sn, "Matte Tin"
11. What material will be used
for BGA solder balls?
Sn / 4.0%Ag / 0.5%Cu (SAC) (Tin / 4.0% Silver
/ 0.5% Copper)
12. What about the Whisker
phenomena on Tin?
Matte Tin and a thickness > 5µm was
chosen to reduce the potential risk of Whiskers.
During qualification at our subcons there were
excessive analysis done on this issue. The executed
reliability tests proved that with the qualified
plating process parameters no Whiskers will
grow.
13. Why are there no problems
with Whiskers on laminate (BGA) devices?
Laminate devices as BGAs are no affected because
this phenomena is related only to plating process
not to solder balls.
14. What does MSL mean and
why is it so important?
MSL stands for Moisture Sensitivity Level.
This classification means that a package is
classified according the IPC/JEDEC J-STD-020C
standard “Moisture/Reflow Sensitivity
Classification for Nonhermetic Solid State Surface
Mount Devices” so that the parts can be
properly packaged, stored, and handled to avoid
damage during assembly solder reflow attachment
and/or repair operations.
This classification procedure applies to all
nonhermetic solid state Surface Mount Devices
(SMDs) in packages, which, because of absorbed
moisture, could be sensitive to damage during
solder reflow.
The vapor pressure of moisture inside a nonhermetic
package increases greatly when the package is
exposed to the high temperature of solder reflow.
Under certain conditions, this pressure can
cause internal delamination of the packaging
materials from the die and/or leadframe/substrate,
internal cracks that do not extend to the outside
of the package, bond damage, wire necking, bond
lifting, die lifting, thin film cracking, or
cratering beneath the bonds. In the most severe
case, the stress can result in external package
cracks. This is commonly referred to as the
‘‘popcorn’’ phenomenon
because the internal stress causes the package
to bulge and then crack with an audible ‘‘pop.’’
SMDs are more susceptible
to this problem than through-hole parts because
they are exposed to higher temperatures during
reflow soldering. The reason for this is that
the soldering operation must occur on the same
side of the board as the SMD device. For through-hole
devices, the soldering operation occurs under
the board that shields the devices from the
hot solder.
15. How are the new MSL-classifications
done?
austriamicrosystems AG is using the IPC/JEDEC
J-STD-020C standard “Moisture/Reflow Sensitivity
Classification for Nonhermetic Solid State Surface
Mount Devices”. The products are classified
according to package size (thickness and volume).
Peak Temperature according IPC/JEDEC
J-STD-020C:
Package Thickness |
Volume
<350 mm³ |
Volume
350 – 2000 mm³ |
Volume
> 2000 mm³ |
<1.6 mm |
260 +0°C |
260 +0°C |
260 +0°C |
1.6 – 2.5 mm |
260 +0°C |
250 +0°C |
245 +0°C |
> 2.5
mm |
250 +0°C |
245 +0°C |
245 +0°C |
For all package families at least MSL3 was
archived.
16. Is a Pb containing component
compatible with a Pb-free solder paste?
Products with Pb containing lead finishes shall
not be assembed using the necessary higher soldering
temperatures required by Pb-free solder pastes.
This can lead to de-wetting of the leads or
holes in the solder balls. Also the used material
sets are not suitable for the higher temperatures
which can result in a damaged device.
17. Is a Pb-free component
compatible with SnPb solder paste?
For leaded /leadframe packages (as SOIC, QFP,
QFN..), several studies done in the industry
showed a good board reliability. The visual
appearance of the solder joints may differ from
today's standards. Some process adaptation might
be necessary.
For laminate (BGAs) packages it is not recommended
to mix Pb-free balls with Pb containing solder
pastes or Pb containing balls with Pb-free pastes
because there will be a potential reliability
risk to the balls due to the mixing.
18. Which changes will be necessary
in customer processes when using Pb-Free components
Solder Paste
For Pb-free packages using Pb-free surface mount
process, the flux chemistry needs to be modified
in order to meet high temperature reflow requirement.
If voiding occurs, the user needs to work with
solvent or resin systems to alleviate the problem.
Check with your solder paste vendor for support.
Pb-Free Reflow Temperature Profile
Currently, there is no industry standard for
Pb-free temperature profiles for surface mount.
The profile is recommended by paste/flux supplier
and needs to be modified, based on specific
application, to achieve optimum reflow process.
Pb-free packages are compliant to the needed
higher reflow temperature.
Customers are encouraged to work with their
solder paste and reflow process equipment suppliers
to develop the optimum temperature profile for
their application.
19. What is the marking convention
for Pb-free devices?
Currently you will find on the
device a line which defines the Assembly lot
code.
The format for this code is YYWWIXX
YY...last two digits of the current
year,
WW...manufacturing week
I...plant identifier
XX...traceability code
This Assembly lot code will be changed for
Pb-free
to AYWWIXX (0335MAA --> A335MAA)
A…Pb-free identifier
Y... last digit of the current year
WW...manufacturing week
I...plant identifier
XX...traceability code
We will adopt an industry standard marking
in place of our Pb Free marking, if an industry
standard is developed and if it is possible
(depending on package size).
20. Is there a possibility
to recognize Pb-free parts in their reels, trays
or boxes?
Currently there are 2 different possibilities
to recognize a Pb-free part in it's packaging:
1)On the MSL label for SMD there is a print
“Pb-free”, for THM devices the
2nd level interconnect label according JEDEC
Standard JESD97 is used.
(SMD -> surface mount device, THM ->
through hole mount)
2) On the barcode label on the boxes, dry
pack bags and reels there will be “Pb-free/
RoHS compliant sign. The Pb-free category
according JEDEC Standard JESD97 is included
too.
21. Does austriamicrosystems
AG choice of molding compounds contain inorganic
Phosphorus?
We understand customers have concern regarding
a molding compound that contained red phosphorus,
which caused failures in (other companies’)
products.
The molding compound in question was later recalled
by the manufacturer.
austriamicrosystems AG never used the molding
compound in question.
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