RoHS, Lead-Free, and Equipment Reliability Reports from the

1
Whats Creeping Around Your Data Center?

• RoHS, Lead-Free, and Equipment Reliability
  Reports from the Field

Chris Muller, Technical Director Purafil, Inc.
2
Introduction WEEE

• To address hazardous waste issues, the member
  states of the European Union created the Waste
  Electrical and Electronics Equipment (WEEE)
  directive. Its purposes were
• Improve manufacturers designs to reduce the
  creation of waste,
• Make manufacturers responsible for certain phases
  of waste management,
• Separate collections of electronic waste (from
  other types of waste), and
• Create systems to improve treatment, refuse, and
  recycling of WEEE.

3
Introduction WEEE (2)

• The WEEE directive laid the groundwork for
  additional legislation and a proposal called EEE
  (Environment of Electrical Electronics
  Equipment).
• This policy is generally referred to as the RoHS
  Directive and is often referred to as Lead-Free
  legislation.
• This is not a very accurate nickname, because it
  extends to other pollutants as well.
• However, they do take it seriously in Europe.

4
The RSA WEEE Man
The WEEE man, designed by Paul Bonomini, is a
huge robotic figure made of scrap electrical and
electronic equipment. It weighs 3.3 tons and
stands 23 feet tall representing the average
amount of electronic products every single one of
us throws away over a lifetime.
Royal Society for the encouragement of Arts,
Manufactures and Commerce Removing Barriers to
Social Progress
5
European Union directive 2002/95/EC

• EU directive 2002/95/EC on the Restriction of
  the use of certain Hazardous Substances in
  electrical and electronic equipment or RoHS was
  implemented in July 2006.
• Applies to electrical and electronic equipment
  designed for use with a voltage rating not
  exceeding 1,000 volts for alternating current and
  1,500 volts for direct current.
• The requirements of this directive are applicable
  to the member states of the European Union.

6
RoHS Directive

• Restricts the use of hazardous substances in
  electrical and electronic equipment.
• Lead (Pb)
• Mercury (Hg)
• Hexavalent chromium (Cr(VI))
• Cadmium (Cd)
• Polybrominated biphenyls (PBB)
• Polybrominated diphenyl ethers (PBDE).
• Contributes to the protection of human health.
• Environmentally sound recovery and disposal of
  waste electrical and electronic equipment.

7
RoHS Directive (2)

• All applicable products in the EU market must now
  pass RoHS compliance.
• RoHS impacts the entire electronics industry and
  compliance violations are costly.
• Product quarantine, transport, rework, scrap,
  lost sales and man-hours, legal action, etc.
• Non-compliance reflects poorly on brand and image
  and undercuts ongoing environmental and due
  diligence activities.

8
Where is RoHS in Effect?

• All EU member countries
• WEEE and RoHS rules, while laid down at the
  European level, are put into law at the national
  level.
• The EU law simply serves as a template for
  national laws, which may differ considerably.
• Croatia, Norway, and Switzerland
• May have legislation implementing
• EU WEEE and RoHS rules, or
• similar legislation.

9
China RoHS

• China RoHS regulations have also been put into
  effect.
• Many consider them to be considerably more
  restrictive.
• Without exemptions, it is impossible to build a
  compliant board

China RoHS Phase 2 Hard Data Reveals a Red
Flag Jim Dills - The Goodbye Chain Group, Feb 15,
2007
10
RoHS in the U.S.

• U.S. State Bills
• California SB20 has the same requirements as EU
  RoHS except that its scope includes only products
  with displays larger than 4.
• California AB2202 includes all EU RoHS
  products.
• Minnesota patterned after EU RoHS, however only
  for consumer products.
• Several other states are looking at RoHS
  legislation.

11
Other RoHS Legislation

• RoHS regulations are also either in effect or
  pending in many countries. Additional RoHS-like
  regulations include
• Argentina has both a WEEE and RoHS bill.
• Japan recently adopted RoHS labeling
  requirements for certain products.
• Taiwan has a voluntary RoHS program.
• Korea is considering RoHS legislation.
• Australia is conducting a survey.

12
Get the Lead Out!

• An aim shared by almost all RoHS legislation is
  the elimination of lead in electronic products.
• The main issue for the electronics industry
  became the use of lead in the manufacture of
  components and circuit board assemblies.
• PCBs have conducting layers on their surface
  typically made of thin copper foil.
• Unprotected copper will oxidize and deteriorate.
• Traditionally, any exposed copper was plated with
  lead(-based) solder by the hot air solder
  leveling (HASL) process.

13
Get the Lead Out! (2)

• HASL has been working well for many years
• Predominant surface finish used in the industry.
• Cheapest PCB available.
• RoHS essentially makes PCBs using HASL process
  obsolete.
• Failure modes on lead-free PCB finishes such as
  OSP and ENIG make these undesirable.
• Alternatives such as ImmAg and OCC are currently
  used as board finishes.
• Due to processing difficulties with OCC boards,
  ImmAg boards quickly became the standard PCB
  finish.

14
Get the Lead Out! (3)

• Immersion silver would seem to have a bright
  future under RoHS.
• Easy to apply to the boards.
• Relatively inexpensive.
• Usually performs well.
• Although ENIG has a larger market share, more
  immersion silver process lines have been
  installed in PCB facilities than any other
  finish.
• Complaints about issues with corrosion.
• Can lead to shorts and ultimate failure of the
  board.

15
Data Center Environments

• Data centers are designed to provide a
  contaminant-free environment by (primarily)
  maximizing the control of airborne particulates.
• Particulate filtration is a "mature" science and
  can be easily applied.

16
Data Center Environments (2)

• The control of gaseous contaminants is critical
  in providing a truly "clean" data center
  environment.
• Gaseous contaminant control can be achieved by
  using chemical filtration systems employing one
  or more chemical filtration media.
• Packed-bed gas-phase air filtration systems are
  most commonly used.
• Adsorbent-loaded fiber filters and combination
  particulate/chemical filters are also being used.

17
What is Gaseous Contamination?

• Solids (Particulates) - 0.003 to 100 microns
• Dust, Smoke
• Liquids ( vapors) - 1 to 9 microns
• Vapors, Aerosols
• Gases - 0.0003 to 0.007 microns
• Sulfur dioxide (SO2), nitrogen dioxide (NO2),
  ozone (O3), formaldehyde (HCHO), hydrogen sulfide
  (H2S), chlorine (Cl2)

18
Particulates vs. Gaseous Contaminants
BACTERIA
PLANT SPORES
VIRUSES
INSECTICIDE DUST
FERTILIZER
COAL DUST
TOBACCO SMOKE
COOKING SMOKE/GREASE
HOUSEHOLD DUST
HUMAN HAIR
PET DANDER
1
10 100
0.0001
0.001
0.01
0.1
Particle Size, Microns
19
Control Methods

• Source Control
• Remove the source(s) of contaminants.
• Ventilation Control
• Introduce clean air into the space.
• Removal Control
• Control contaminants by physical or chemical
  means.

20
Air Quality in the U.S.

• AirData Website Provides access to yearly
  summaries of U.S. air pollution data, taken from
  EPA's air pollution databases.
• Includes all 50 states plus District of Columbia,
  Puerto Rico, and the U. S. Virgin Islands.
• Has information about where air pollution comes
  from (emissions) and how much pollution is in the
  air outside our homes and work places
  (monitoring).

http//www.epa.gov/oar/data/
21
Air Quality in the U.S. (2)

• Monitoring sites report data to EPA for these six
  criteria air pollutants
• Carbon monoxide (CO)
• Nitrogen dioxide (NO2)
• Ozone (O3)
• Sulfur dioxide (SO2)
• Particulate matter (PM10 and PM2.5)
• Lead (Pb)
• AirData information is from two EPA databases.
• National Emissions Inventory (NEI) Database
• Air Quality System (AQS) Database - Monitoring
  Data

22
Air Quality in the U.S. (3)

• Historically the U.S. EPA has identified part or
  all of 463 counties in 31 states and the District
  of Columbia as having air quality that violates
  the federal air standard for ozone (O3, commonly
  called smog).
• These ozone nonattainment areas encompass a
  total population of almost 160 million people or
  more than 54 of the population!!!

23
Nonattainment Areas for O3 - USA
24
AIRNow Air Quality Index (AQI)
25
Air Quality in Atlanta

• Air pollution no longer just Atlanta's
  problemby The Associated Press
• "Atlanta once was the poster child for bad air.
  Now we're seeing mid-sized cities grapple with
  the same problems," said Ciannat Howett, director
  of the Atlanta office of the Southern
  Environmental Law Center.

26
Air Quality in Atlanta (2)

• 24 Counties 4.4 million people gt50 of the
  population!!

27
Motor Vehicle Exhaust

• There are six main classes of gaseous
  contaminants which are routinely described in
  motor vehicle exhaust.

Emission factors in pounds per 1000 gallons of
fuel
28
Emissions from Diesel Engines

• Toxic compounds, like polyaromatic hydrocarbons
  (PAH), are found in diesel engine exhaust.

CO - carbon monoxide, HC hydrocarbons, DPM -
diesel particulate matter, NOx - nitrogen oxides,
SO2 - sulfur dioxide
29
Corrosion and Electronic Circuits
Pictures courtesy of IBM Global Services
30
Corrosion and Electronic Circuits (2)

• High reliability expected in an environmentally
  -controlled data center.
• Electronics do not simply wear out.
• Causes of electronics failures
• Electrical power quality,
• lightning, electrostatic
• discharge.
• Contamination and
• corrosion.
• Outdoor and indoor pollutants
• (gases and vapors), liquid
• (water), particulates (dirt, dust).

31
Causes of Corrosion

• Particulate Matter - ?
• Relative Humidity - ?
• Temperature - ?
• Gaseous Contaminants - ?

32
Corrosive Chemical Gases

• Active sulfur compounds (H2S)
• Sulfur oxides (SO2, SO3)
• Nitrogen oxides (NOx)
• Inorganic chlorine compounds (Cl2, ClO2, HCl)
• Hydrogen fluoride (HF)
• Ammonia and derivatives (NH3, NH4)
• Photochemical species (O3)
• Strong oxidants

33
How Corrosion Occurs
Acid gases react with metals to form
non-conductive salts. As salt builds up, the
salt is forced back up through the pores of the
metal onto its surface, thus causing disruption
of the contact point.
34
Types and Effects of Corrosion

• Pore Corrosion
• Electrical contacts coated with noble metals.
• Underlying metal corrodes through pores in top
  coating.
• Corrosion migrates to
• the contact surface
• and increases contact
• resistance.

35
Types and Effects of Corrosion (2)

• Creep Corrosion
• The result of copper or silver corrosion growing
  (or creeping) over the noble metal top coating.
• This corrosion forms
• a non-conductive film
• on the contact surface
• and inhibits the flow
• of current.

36
Types and Effects of Corrosion (3)

• Via Corrosion
• Exposed copper, such as the inside of via
  barrels.
• Where the via hole is not completely coated,
  copper metal is vulnerable to atmospheric attack.

• Review of dozens of incidents and hundreds of
  failures in an environment high in reduced sulfur
  gases (e.g., H2S) showed the majority of the
  failures show the heaviest corrosion mainly
  inside the via holes.

37
Types and Effects of Corrosion (4)

• Whisker growth
• Growth of microscopic crystals out of a
  conductive metal.
• May cause untraceable
• alarms and other
• random occurrences
• by creating circuit
• paths for current to
• flow.

38
Electronic Equipment Corrosion

• CAUSE Capillary condensation on particulates.

39
Electronic Equipment Corrosion (2)
BEFORE CLEANING
AFTER CLEANING
40
Electronic Equipment Corrosion (3)
41
Electronic Equipment Corrosion (4)
AFTER REMOVING DUST THERE IS EVIDENCE OF BRIDGING
CORROSION SALTS ARE HARD TO REMOVE AND ACT AS
INSULATORS
42
Environmental Assessment
43
Standards for Air Quality

• ISA Standard S71.04-1985 - "Environmental
  Conditions for Process Measurement and Control
  Systems Airborne Contaminants
• IEC Standard, 60654-4 (1987-07) - "Operating
  Conditions for Industrial-Process Measurement and
  Control Equipment. Part 4 Corrosive and Erosive
  Influences
• JEIDA Standard 29-1990 - "Standard for Operating
  Conditions of Industrial Computer Control System

44
Standards for Air Quality (2)

• These standards define or characterize
  environments in terms of the overall corrosion
  potential.
• Using "reactivity monitoring," a quantitative
  measure of this potential can be established.

45
Standards for Air Quality (3)

• Four levels of corrosion severity have been
  established by ISA-S71.04.
• The optimum severity level is G1 - Mild.
• At this level, corrosion is not a factor in
  determining equipment reliability.
• As the corrosive potential of an environment
  increases, the severity level will be classified
  as G2, G3 and GX (the most severe).
• The effects of humidity and temperature are also
  quantified in this standard.
• Relative humidity of less than 50 percent is
  specified by the standard.

46
Standards for Air Quality (4)
47
Effects of Corrosive Contaminants
48
Air Quality in Atlanta vs. ISA Standard

• AQI for Atlanta (07 08 data)
• SO2 1 17 ppb Average 8.3 ppb
• G1/G2 (lt10 ppb) Average G1
• NO2 1 105 ppb Average 63.5 ppb
• G1/G2 (lt50 ppb) Average G2
• O3 1 126 ppb Average 16.39 ppb
• G1/GX (lt2 ppb) Average G2

Note ozone (O3) catalyzes the conversion of
nitrogen dioxide (NO2) to nitric acid (HNO3).
Therefore, control of ozone is critical to
achieving and maintaining acceptable air quality
levels.
49
Reactivity (Corrosion) Monitoring

• Environmental monitoring technique using copper
  and/or silver corrosion rates.
• Many of the gaseous contaminants targeted for
  control in data centers are corrosive in nature
  and can be easily measured using reactivity
  monitoring.
• Both passive and real-time reactivity monitors
  are available.

50
Reactivity Monitoring (2)

• Silver Coupons - sensitive to lower levels of
  contaminants, detects chlorine, and identifies
  sulfur species (i.e., H2S vs. SO2).
• Reactivity and severity levels have not been
  formally established.
• Purafil has the largest database of silver coupon
  data (gt10,000 locations).
• Used to obtain a more accurate assessment of the
  corrosive potential of an environment.
• Gold Coupons - indicator of damage to gold-plated
  contacts.
• Provides a visual indication of corrosive damage.
• Gauges porosity of metal plating.

51
Real-Time Corrosion Monitoring

• Continuous Corrosion Transmitter (CCT)
• Direct 4-20 mA digital or analog output to
  facility management system.
• Copper and silver sensors available.
• No RH or Temperature monitoring.

52
Real-Time Corrosion Monitoring (2)

• Atmospheric Corrosion Monitor (ACM)
• Microprocessor-controlled device that
  continuously monitors the amount of corrosion
  attributable pollutant gases.
• Can be operated as a battery-operated data
  logging system or wired into a central computer
  system.
• Can also monitor temperature and RH.

53
Chemical Filtration Systems

• Removal of corrosive contaminant gases and odors.
• Protection for people.
• Extends the life of data center equipment.
• Provides for savings due to reduced energy
  consumption.

54
Chemical Filtration Systems (2)

• Prefilter Section
• Removes unwanted particulate matter.
• Protects chemical filtration media.
• Chemical Filter Section(s)
• Removes unwanted gases and odors.
• Protects equipment and personnel.
• Final Filter Section

55
Chemical Filtration System (3)

• Computer Air Recirculation Equipment (C.A.R.E.)
• In-room, self-contained unit designed to draw air
  directly from under the raised floor in a data
  center.
• Used to provide clean recirculation air to areas
  with low-to-moderate gaseous contaminant levels.
• The C.A.R.E. system contains a pre-filter, one or
  two banks of chemical filters, a blower section,
  and a 90 final filter.
• The unit is also used to further clean and polish
  room air in order to maintain very low gas
  contaminant levels.

56
Application Data Centers

• The Problem damage to servers, hard disk drives,
  and other electronic equipment reducing
  reliability, increasing cost of maintenance, and
  potentially leading to data loss.
• Contaminant Gases sulfur dioxide, nitrogen
  dioxide, ozone, chlorine, acetic acid, organic
  acids, formaldehyde

57
Application Data Centers (2)

• The Basic Concept - pressurize the protected
  space with clean air - blow it up like a balloon!

58
What will this require?

• Room Air Purification
• Pressurize the room to 0.05-0.10 IWG with clean
  air (3 to 6 air changes per hour)
• Humidity Control
• lt50 Relative Humidity (with less than a 6
  change per hour)
• Temperature Control
• 70 2F
• Room Construction and Integrity
• Well-sealed room double airlock entryways
• Room Air Recirculation
• 6 to 12 air changes per hour

59
Cost Justification

• Monitoring the environment can prevent potential
  problems.
• 50,000Å / year corrosion creep across
  insulation and PCB traces expected in 4-6 months
• 20,000Å / year wire wrap failures expected in
  2-3 months
• 7,000Å / year IC socket failures expected in
  6-8 months
• 4,000Å / year edge card intermittents expected
  in 6-8 months
• 2,500Å / year dielectric failures expected in
  2-3 years
• 1,000Å / year edge card intermittents expected
  in 1-3 years
• 800Å / year edge card failures expected in 4-5
  years

60
Case Study ABC Bank, Jinan Shandong

• Primary criteria for chemical filtration
• Achieve ISA Class G1 conditions in data center.
• Required 80 reduction in existing corrosion
  levels.
• Installation of one air cleaning system for
  outside air and two recirculating air cleaning
  systems for inside the data center.
• Also installed real-time corrosion monitor.
• Annual replacement of chemical media and
  particulate filters based on CCC results and
  associated contaminant levels.
• Complete filter change out 4,000.

61
Case Study Summary

• Summary of corrosion rates before and after
  installation of chemical filtration equipment and
  percent reduction.
• After start up ISA Class G1 conditions were
  achieved in all locations.

62
Case Study Summary (2)

• Cost of Ownership
• Initial cost of approx. 0.30-0.35 / ft3.
• 26,230 / 80,000 ft3 0.33/ft3 of data center
  space (avg.)
• Annual maintenance of approx. 0.05-0.07 / ft3.
• 4,000 / 80,000 ft3 0.05/ft3 of data center
  space (avg.)

63
QPL Ltd. Dong Guan, China
Leadframe Samples

• Trace amounts of sulfur were found to be
  associated with the silver layer.
• Sulfur dioxide, hydrogen sulfide, nitrogen oxides
  were measured in outdoor air.
• Sulfur was not detected on the copper or the
  iron-nickel region.
• This is consistent in a temperature and
  humidity-controlled environment.

64
Were Not Alone!

• Rockwell Automation study looking at lead-free
  finishes, four alternate PCB finishes were
  subjected to an accelerated mixed flowing gas
  corrosion test.
• The immersion gold (ENIG) and immersion silver
  (ImmAg) surface finishes failed early in the
  testing.
• These coatings are the most susceptible to
  corrosion failures and are expected to be much
  more susceptible than traditional HASL coatings.
• The use of these two coatings may make the PCB
  the weak link with regard to the sensitivities of
  the electronic devices to corrosion.
• None of the coatings can be considered immune
  from failure in an ISA Class G3 environment.
• The gold and silver coatings could not be
  expected to survive a mid to high Class G2
  environment based on these test results.

65
Were Still Not Alone!

• ERA Technology reports Recent research has shown
  that printed circuit boards made using lead-free
  materials can be more susceptible to corrosion
  than their tin/lead counterparts
• Industry is working diligently to address these
  concerns but they cannot be addressed overnight.
• Reliability and Failure Analysis Group has
  diagnosed failures in electronic devices due to
  interaction with low levels of gaseous sulfides.
• Showed that corrosion could occur even with
  measured hydrogen sulfide levels as low as
  0.2µg/m3 (0.14 ppb).
• Formation of a 200Å thick layer of silver sulfide
  in 100 hours at a concentration of just 100 µg/m3
  72 ppb.

66
Changes Are Coming

• Dell, Inc. has characterized data center
  environments based on the ISA Standard.
• ISA Class G2 Moderate
• Considered to be High Sulfur environment.
• Current coatings will provide protection in G1 or
  G2 environments.
• Class G3 Harsh
• Considered to be Excessive Sulfur environment.
• Specifications call for maximum of G2
  environments for Dell data center equipment.
• G3 or GX classifications will void warranties.

67
Data Center Customers (partial list)
68
Its Not Just Data Centers!

• The ISA Standard is becoming irrelevant because
  it does not take into account silver corrosion.
  All of the new RoHS compliant equipment I have
  purchased over the last year contains silver and
  the failure rate for some components is now being
  measured in weeks instead of years.
• Grant Crosley, Visy Paper

69
Conclusions

• The issue and potential for corrosion-related
  problems in data centers has been presented.
• Data from many different sites shows that
  corrosive atmospheres exist in locations that
  most would consider otherwise benign if not for
  the changes in electronics mandated by RoHS
  legislation.
• These problems can be addressed by continuous
  monitoring of the data center environment and
  removal and control of corrosive contaminants
  where indicated.

70
Conclusions (2)

• Ultimately, the successful implementation of a
  corrosion protection program requires
• Knowledge and understanding that corrosion of
  electronic equipment is a serious problem.
• Commitment to a monitoring program to describe
  the potential for electronic equipment failure.
• Commitment to an integrated contamination control
  system.
• Commitment to take corrective action whenever
  necessary.

71
Summary

• Computer systems and components used in data
  centers are protected against fire, power, shock,
  humidity, temperature and particulate
  contamination.
• Unfortunately, the potential damage to equipment
  caused by the corrosive effects of gaseous
  contaminants due to RoHS compliance has not been
  fully recognized or addressed.
• Manufacturers have to comply with RoHS if they
  want to continue to do business in the EU, China,
  etc.,
• Many have taken the ImmAg route as their path to
  compliance.
• This has taken care of one issue but has
  presented new challenges with regards to
  equipment reliability.

72
Contact Information

• For more information on this subject or to
  request a copy of this presentation, please
  contact
• Chris Muller
• Purafil, Inc.
• 2654 Weaver Way
• Doraville, Georgia 30340
• Tel [phone] x341
• Fax [phone]
• E-mail cmuller_at_purafil.com
• www.purafil.com