EN IEC 61189-5-504:2020

Test methods for electrical materials, printed board and other interconnection structures and assemblies - Part 5-504: General test methods for materials and assemblies - Process ionic contamination testing (PICT)

IEC 61189-5-504:2020 is a test method designed to determine the proportion of soluble ionic residues present upon a circuit board, electronic component or assembly. The conductivity of the solution used to dissolve the ionic residues is measured to evaluate the level of ionic residues.

Prüfverfahren für Elektromaterialien, Leiterplatten und andere Verbindungsstrukturen und Baugruppen – Teil 5-504: Allgemeine Prüfverfahren für Materialien und Baugruppen – Prüfung der ionischen Verunreinigung bei Prozessen (PICT)

Méthodes d’essai pour les matériaux électriques, les cartes imprimées et autres structures d’interconnexion et ensembles - Partie 5-504: Méthodes d’essai générales pour les matériaux et les ensembles - Essai de contamination ionique des procédés (PICT)

L'IEC 61189-5-504:2020 est une méthode d'essai conçue pour déterminer la proportion de résidus ioniques solubles sur une carte à circuit imprimé, un composant électronique ou un ensemble. La conductivité de la solution utilisée pour dissoudre les résidus ioniques est mesurée afin d'évaluer le niveau des résidus ioniques.

Preskusne metode za električne materiale, tiskane plošče ter druge povezovalne strukture in sestave - 5-504. del: Splošne preskusne metode za materiale in sestave – Preskušanje procesa ionskega onesnaženja (PICT)

General Information

• Status: Published
• Publication Date: 11-Jun-2020
• ICS: 31.180 - Printed circuits and boards
• Technical Committee: CLC/SR 91 - Electronics assembly technology
• Drafting Committee: IEC/TC 91 - IEC_TC_91
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 12-Jun-2020
• Completion Date: 12-Jun-2020
• Ref Project: SIST EN IEC 61189-5-504:2020 - Test methods for electrical materials, printed boards and other interconnection structures and assemblies - Part 5-504: General test methods for materials and assemblies - Process ionic contamination testing (PICT)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN IEC 61189-5-504:2020
01-oktober-2020
Preskusne metode za električne materiale, tiskane plošče ter druge povezovalne
strukture in sestave - 5-504. del: Splošne preskusne metode za materiale in
sestave – Preskušanje procesa ionskega onesnaženja (PICT)

Test methods for electrical materials, printed boards and other interconnection structures

and assemblies - Part 5-504: General test methods for materials and assemblies -
Process ionic contamination testing (PICT)
Ta slovenski standard je istoveten z: EN IEC 61189-5-504:2020
ICS:
31.180 Tiskana vezja (TIV) in tiskane Printed circuits and boards
plošče
31.190 Sestavljeni elektronski Electronic component
elementi assemblies
SIST EN IEC 61189-5-504:2020 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN IEC 61189-5-504:2020
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SIST EN IEC 61189-5-504:2020
EUROPEAN STANDARD EN IEC 61189-5-504
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2020
ICS 31.180
English Version
Test methods for electrical materials, printed board and other
interconnection structures and assemblies - Part 5-504: General
test methods for materials and assemblies - Process ionic
contamination testing (PICT)
(IEC 61189-5-504:2020)

Méthodes d'essai pour les matériaux électriques, les cartes Prüfverfahren für Elektromaterialien, Leiterplatten und

imprimées et autres structures d'interconnexion et andere Verbindungsstrukturen und Baugruppen - Teil 5-

ensembles - Partie 5-504: Méthodes d'essai générales pour 504: Allgemeine Prüfverfahren für Materialien und

les matériaux et les ensembles - Essai de contamination Baugruppen - Prüfung der ionischen Verunreinigung bei

ionique des procédés (PICT) Prozessen (PICT)
(IEC 61189-5-504:2020) (IEC 61189-5-504:2020)

This European Standard was approved by CENELEC on 2020-05-26. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the

Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN IEC 61189-5-504:2020 E
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SIST EN IEC 61189-5-504:2020
EN IEC 61189-5-504:2020 (E)
European foreword

The text of document 91/1639/FDIS, future edition 1 of IEC 61189-5-504, prepared by IEC/TC 91

"Electronics assembly technology" was submitted to the IEC-CENELEC parallel vote and approved by

CENELEC as EN IEC 61189-5-504:2020.
The following dates are fixed:

• latest date by which the document has to be implemented at national (dop) 2021-02-26

level by publication of an identical national standard or by endorsement

• latest date by which the national standards conflicting with the (dow) 2023-05-26

document have to be withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice

The text of the International Standard IEC 61189-5-504:2020 was approved by CENELEC as a

European Standard without any modification.
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SIST EN IEC 61189-5-504:2020
EN IEC 61189-5-504:2020 (E)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments)

applies.

NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the relevant

EN/HD applies.

NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:

www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60068-1 - Environmental testing - Part 1: General and EN 60068-1 -
guidance
IEC 60068-2-20 - Environmental testing - Part 2-20: Tests - EN 60068-2-20 -
Test T: Test methods for solderability and
resistance to soldering heat of devices with
leads
IEC 60068-2-58 - Environmental testing - Part 2-58: Tests - EN 60068-2-58 -
Test Td: Test methods for solderability,
resistance to dissolution of metallization
and to soldering heat of surface mounting
devices (SMD)
IEC 60079-7 - Explosive atmospheres - Part 7: Equipment EN 60079-7 -
protection by increased safety "e"
IEC 60194 - Printed board design, manufacture and - -
assembly - Terms and definitions
IEC 61189-5-502 - Test methods for electrical materials, - -
printed boards and other interconnection
structures and assemblies - Part 5-502:
General test methods for materials and
assemblies - Surface insulation resistance
(SIR) testing of assemblies
IEC 61190-1-3 - Attachment materials for electronic EN IEC 61190-1-3 -
assembly - Part 1-3: Requirements for
electronic grade solder alloys and fluxed
and non-fluxed solid solder for electronic
soldering applications
IPC-TM-650 - Surface Insulation Resistance - -
method 2.6.3.7
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SIST EN IEC 61189-5-504:2020
EN IEC 61189-5-504:2020 (E)
IPC 9202 - Material and Process Characterisation / - -
Qualification Test Protocol for Assessing
Electrochemical Performance
IPC 9203 - Users Guide to IPC 9202 and the IPC-B-52 - -
Standard Test Vehicle
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SIST EN IEC 61189-5-504:2020
IEC 61189-5-504
Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Test methods for electrical materials, printed board and other interconnection
structures and assemblies –
Part 5-504: General test methods for materials and assemblies – Process ionic
contamination testing (PICT)
Méthodes d'essai pour les matériaux électriques, les cartes imprimées et autres
structures d'interconnexion et ensembles –
Partie 5-504: Méthodes d'essai générales pour les matériaux et les ensembles –
Essai de contamination ionique des procédés (PICT)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.180 ISBN 978-2-8322-8111-6

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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SIST EN IEC 61189-5-504:2020
– 2 – IEC 61189-5-504:2020  IEC 2020
CONTENTS

FOREWORD ........................................................................................................................... 4

1 Scope .............................................................................................................................. 6

2 Normative references ...................................................................................................... 6

3 Terms and definitions ...................................................................................................... 7

4 General description of the test ......................................................................................... 7

5 Test apparatus ................................................................................................................ 7

6 Materials ......................................................................................................................... 8

6.1 Test solution ........................................................................................................... 8

6.1.1 General ........................................................................................................... 8

6.1.2 Deionised water (DI) ........................................................................................ 8

6.1.3 Propan-2-ol ..................................................................................................... 9

6.2 Calibration solution ................................................................................................. 9

6.3 Test chamber .......................................................................................................... 9

6.4 Regeneration filter column ...................................................................................... 9

6.5 Recirculating pump ................................................................................................. 9

6.6 Measurement system capability .............................................................................. 9

7 Test procedure ................................................................................................................ 9

7.1 Test apparatus ........................................................................................................ 9

7.2 Closed loop ........................................................................................................... 10

7.3 Open loop ............................................................................................................. 11

7.4 System verification ................................................................................................ 12

7.4.1 General ......................................................................................................... 12

7.4.2 Polishing the test solution .............................................................................. 12

7.4.3 Recording test solution temperature and specific gravity................................ 12

7.4.4 Checking conductivity accuracy ..................................................................... 13

7.5 Procedure ............................................................................................................. 14

7.5.1 Specimen handling ........................................................................................ 14

7.5.2 General ......................................................................................................... 14

7.5.3 Closed loop ................................................................................................... 14

7.5.4 Open loop ...................................................................................................... 15

7.5.5 Influence of CO ............................................................................................ 15

8 Measurement Methods .................................................................................................. 16

8.1 Method 1............................................................................................................... 16

8.2 Method 2............................................................................................................... 17

Annex A (normative) Test technique .................................................................................... 18

A.1 Conductivity signal ................................................................................................ 18

A.2 DI water correction ................................................................................................ 18

A.3 Conductivity of the ionic solution ........................................................................... 19

A.3.1 General ......................................................................................................... 19

A.3.2 Conductivity differences................................................................................. 20

A.4 Test solution temperature ..................................................................................... 20

A.4.1 General ......................................................................................................... 20

A.4.2 Linear temperature ........................................................................................ 20

A.4.3 Leaching effects ............................................................................................ 20

A.5 Conversion of conductivity to contamination .......................................................... 21

A.6 Calibration ............................................................................................................ 21

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SIST EN IEC 61189-5-504:2020
IEC 61189-5-504:2020  IEC 2020 – 3 –

Annex B (informative) Measurement methods ...................................................................... 22

B.1 Method 1............................................................................................................... 22

B.2 Method 2............................................................................................................... 24

Bibliography .......................................................................................................................... 25

Figure 1 – Typical test instrument ........................................................................................... 8

Figure 2 – Closed-loop method in regeneration mode ........................................................... 10

Figure 3 – Closed loop in test mode ...................................................................................... 11

Figure 4 – Open loop method ................................................................................................ 12

Figure 5 – 50 % specific gravity chart ................................................................................... 13

Figure 6 – 75 % specific gravity chart ................................................................................... 13

Figure 7 – Example of result measuring the influence of CO ............................................... 16

Figure A.1 – Conductivity against voltage curve .................................................................... 18

Figure A.2 – Deionised water correction................................................................................ 19

Figure B.1 – Test pass .......................................................................................................... 23

Figure B.2 – Test fail ............................................................................................................ 23

Table B.1 – Pass/Fail value method 1 worked example ......................................................... 22

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SIST EN IEC 61189-5-504:2020
– 4 – IEC 61189-5-504:2020  IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TEST METHODS FOR ELECTRICAL MATERIALS, PRINTED BOARDS
AND OTHER INTERCONNECTION STRUCTURES AND ASSEMBLIES –
Part 5-504: General test methods for materials and assemblies –
Process ionic contamination testing (PICT)
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

international co-operation on all questions concerning standardization in the electrical and electronic fields. To

this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,

Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC

Publication(s)"). Their preparation is entrusted to technical committees; any IEC National Committee interested

in the subject dealt with may participate in this preparatory work. International, governmental and non-

governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely

with the International Organization for Standardization (ISO) in accordance with conditions determined by

agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence

between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in

the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 61189-5-504 has been prepared by IEC technical committee 91:

Electronics assembly technology.
The text of this International Standard is based on the following documents:
FDIS Report on voting
91/1639/FDIS 91/1644/RVD

Full information on the voting for the approval of this International Standard can be found in

the report on voting indicated in the above table.

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

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SIST EN IEC 61189-5-504:2020
IEC 61189-5-504:2020  IEC 2020 – 5 –

A list of all parts in the IEC 61189 series, published under the general title Test methods for

electrical materials, printed boards and other interconnection structures and assemblies, can

be found on the IEC website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates

that it contains colours which are considered to be useful for the correct

understanding of its contents. Users should therefore print this document using a

colour printer.
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SIST EN IEC 61189-5-504:2020
– 6 – IEC 61189-5-504:2020  IEC 2020
TEST METHODS FOR ELECTRICAL MATERIALS, PRINTED BOARDS
AND OTHER INTERCONNECTION STRUCTURES AND ASSEMBLIES –
Part 5-504: General test methods for materials and assemblies –
Process ionic contamination testing (PICT)
1 Scope

This part of IEC 61189 is a test method designed to determine the proportion of soluble ionic

residues present upon a circuit board, electronic component or assembly. The conductivity of

the solution used to dissolve the ionic residues is measured to evaluate the level of ionic

residues.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their

content constitutes requirements of this document. For dated references, only the edition

cited applies. For undated references, the latest edition of the referenced document (including

any amendments) applies.
IEC 60068-1, Environmental testing – General and guidance

IEC 60068-2-20, Environmental testing – Part 2-20: Tests – Test T: Test methods for

solderability and resistance to soldering heat of devices with leads

IEC 60068-2-58, Environmental testing – Part 2-58: Tests – Test Td: Test methods for

solderability, resistance to dissolution of metallization and to soldering heat of surface

mounting devices (SMD)

IEC 60079-7, Explosive atmospheres – Part 7: Equipment protection by increased safety "e"

IEC 60194, Printed board design, manufacture and assembly – Terms and definitions

IEC 61189-5-502, Test methods for electrical materials, printed boards and other

interconnection structures and assemblies – Part 5-502: General test methods for materials

and assemblies – Surface insulation resistance (SIR) testing of assemblies

IEC 61190-1-3, Attachment materials for electronic assembly – Part 1-3: Requirements for

electronic grade solder alloys and fluxed and non-fluxed solid solder for electronic soldering

applications
IPC-TM-650 method 2.6.3.7, Surface Insulation Resistance

IPC 9202, Material and Process Characterisation / Qualification Test Protocol for Assessing

Electrochemical Performance
IPC 9203, Users Guide to IPC 9202 and the IPC-B-52 Standard Test Vehicle
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SIST EN IEC 61189-5-504:2020
IEC 61189-5-504:2020  IEC 2020 – 7 –
3 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 60068-1,

IEC 60068-2-20:2008, IEC 60068-2-58, IEC 60194, and IEC 61190-1-3 apply.
4 General description of the test

The test measures the conductivity of a test solution that comprises a mixture of de-ionised

water and alcohol (propan-2-ol). The test equipment shall measure the total current flow and

the result shall be expressed as an equivalence of sodium chloride (NaCl) mass per unit area

(μg/cm ≡ NaCl).

The test is used to monitor levels of ionic residues of printed circuit boards, electrical and

electronic components or printed circuit assemblies. The measured values are compared to

the user’s performance specification.

Ionic residues emanate from multiple processes during the manufacture of electronic circuit

boards, components and assemblies. Examples of ionic residues include: ammonium chloride

– citric acid – diethylamine hydrochloride – hydrochloric acid – methylamine hydrohalide –

sulphuric acid – finger salts – carboxilic acid.

When an ionic contaminant comes into contact with water, the conductance value of the water

will increase owing to the dissolution of the contaminant into the water. If the surface area and

the type of contamination are also known it is possible to express the amount of
contamination present, as a given weight per unit area of board.

This test does not measure any surface ionic materials that are not brought into solution

owing to insolubility, physical entrapment or inadequate exposure to the extracting solvent.

Additionally, non-ionic components of the soil are not measured. Not all ionic contaminants

are easily soluble in water, particularly those trapped within process residues such as solder

flux. These contaminants do however have increased solubility in alcohol.

The addition of a strongly ionized salt to deionized water will enhance its electrical

conductance to a degree that is nearly proportional to the concentration of the salt.

Conductance measurement can thus be used to indicate concentration of an ionic salt

extracted into a solution.

Amounts of ionic materials in the test solution are expressed by a conductivity factor that is

equivalent to the measured conductivity contributed by a known amount of a standard,

strongly ionized salt such as sodium chloride (NaCl). Ionic residues are therefore usually

expressed as equivalents of sodium chloride in micrograms per unit surface area (X μg/cm ≡

NaCl) of the sample under test. This does not imply that the contamination is NaCl, but that it

exhibits conductivity equivalence to that of the expressed amount of NaCl if it were in solution

instead of the ionic soil.

Measurements of ionic conductivity obtained by this test method do not differentiate between

different ionic species, they simply measure conductivity that can be related to the total

amounts of ionic materials present in the test solution.
5 Test apparatus

The test requires measurement apparatus, corresponding generally to that shown in Figure 1.

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SIST EN IEC 61189-5-504:2020
– 8 – IEC 61189-5-504:2020  IEC 2020
Key
1 test chamber
2 measurement cell
3 recirculation pump
4 control valve(s)
5 regeneration filter column
6 control valve(s)
Figure 1 – Typical test instrument
6 Materials
6.1 Test solution
6.1.1 General

Ionic soils can be dissociated in water, and the conductance measured to give an indication of

the contaminate level. The test solution however is more than just water; it contains propan-2-

ol, a non-polar liquid that aids the dissolution of the soil and, as a non-ionic hydrophilic

solvent, its presence does not influence the reading except insofar as it "dilutes" the water

bearing the dissociated ions. The test employs a test solution that comprises a specific ratio

of 50 % V/V propan-2-ol and 50 % V/V deionised water or 75 % V/V propan-2-ol and 25 % V/V

de-ionised water.

The 50:50 mixed solution is an optimal compromise between the sensitivity and the solvency

when using immersion test methods.

The 75:25 mixed solution with the higher alcohol content will reduce sensitivity but increase

solvency and vice versa with respect to water.
6.1.2 Deionised water (DI)

The detection of ionic impurities in water uses a well-established conductivity test method.

The electrical conductivity of pure water is 0,055 μS/cm at 25 °C. This value is temperature-

dependent.
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SIST EN IEC 61189-5-504:2020
IEC 61189-5-504:2020  IEC 2020 – 9 –

The addition of 1 × 10 parts of NaCl increases the conductivity of pure water from

0,055 µS/cm to 0,057 µS/cm at 25 °C [1] .
6.1.3 Propan-2-ol

Propan-2-ol, also commonly known as iso-propyl alcohol (IPA), is used to increase the

dissolution of ionic material that is inorganic in nature and trapped by an organic residue.

6.2 Calibration solution

The calibration solution contains a known value of NaCl, typically 0,1 %, and deionised water.

The calibration solution shall be marked with an expiry date and shall not be used beyond this

expiry date.
6.3 Test chamber

For optimum accuracy, the relationship between the test specimen surface area and the

volume of test solution in the test chamber should be 1cm per 10 ml [2].

When testing smaller specimens, the size criterion can be met by testing multiple specimens

simultaneously.

The test chamber should always have a lid to minimise the absorption effect of surrounding

CO and other pollutants.
6.4 Regeneration filter column

The regeneration filter column contains a pre-mixed de-ionising resin that comprises chelate,

cation and anion resins.

The test solution is pumped through the filter column where, by ionic exchange, the solution is

polished until it reaches a predetermined level of conductivity < 0,1 µS/cm.
6.5 Recirculating pump

The test solution is re-circulated by using a pump that shall comply with IEC 60079-7.

6.6 Measurement system capability
The measurement system shall have an accuracy of ±0,05 µS/cm.

The instrument should be capable of avoiding polarisation effects between electrodes such as

those that can occur when using DC test currents. Equally, error signa
...