Semiconductor devices - Mechanical and climatic test methods - Part 20-1: Handling, packing, labelling and shipping of surface mount devices sensitive to the combined effect of moisture and soldering heat (IEC 60749-20-1:2009)

This part of IEC 60749 applies to all non-hermetic SMD packages which are subjected to reflow solder processes and which are exposed to the ambient air. The purpose of this document is to provide SMD manufacturers and users with standardized methods for handling, packing, shipping, and use of moisture/reflow sensitive SMDs which have been classified to the levels defined in IEC 60749-20. These methods are provided to avoid damage from moisture absorption and exposure to solder reflow temperatures that can result in yield and reliability degradation. By using these procedures, safe and damage-free reflow can be achieved, with the dry packing process, providing a minimum shelf life capability in sealed dry-bags from the seal date. Two test conditions, method A and method B, are specified in the soldering heat test of IEC 60749-20. For method A, moisture soak conditions are specified on the assumption that moisture content inside the moisture barrier bag is less than 30 % RH. For method B, moisture soaking conditions are specified on the assumption that manufacturer's exposure time (MET) does not exceed 24 h and the moisture content inside the moisture barrier bag is less than 10 % RH. In an actual handling environment, SMDs tested by method A are permitted to absorb moisture up to 30 % RH, and SMDs tested by method B are permitted to absorb moisture up to 10 % RH. This standard specifies the handling conditions for SMDs subjected to the above test conditions.

Halbleiterbauelemente - Mechanische und klimatische Prüfverfahren - Teil 20-1: Handhabung, Verpackung, Kennzeichnung und Transport oberflächenmontierbarer Bauelemente, die empfindlich gegen die Kombination von Feuchte und Lötwärme sind (IEC 60749-20-1:2009)

Dispositifs à semiconducteurs - Méthodes d'essais mécaniques et climatiques - Partie 20-1: Manipulation, emballage, étiquetage et transport des composants pour montage en surface sensibles à l'effet combiné de l'humidité et de la chaleur de brasage (CEI 60749-20-1:2009)

La CEI 60749-20-1:2009 s'applique aux boîtiers CMS non hermétiques qui sont soumis aux procédés de brasage par refusion et qui sont exposés à l'air ambiant. L'objet de ce document est de fournir aux fabricants et aux utilisateurs de CMS des méthodes normalisées pour la manipulation, l'emballage, le transport et l'utilisation des CMS sensibles à l'humidité/la refusion qui sont classés selon les niveaux définis dans la CEI 60749-20. Ces méthodes sont fournies pour éviter les dommages provoqués par l'absorption d'humidité et l'exposition aux températures de brasage par refusion pouvant donner lieu à une dégradation de rendement et de fiabilité. L'utilisation de ces procédures permet une refusion sûre et ne causant pas de dommages, avec le procédé d'emballage avec dessiccant, ce qui permet une durée minimale de stockage dans des sacs scellés avec dessiccant à compter de la date de scellement.

Polprevodniški elementi - Mehanske in klimatske preskusne metode - 20-1. del: Obdelava, pakiranje, označevanje in pošiljanje elementov za površinsko montažo (SMD), občutljivih na učinkovanje vlage in spajkalne vročine (IEC 60749-20-1:2009)

General Information

Status
Published
Publication Date
15-Jul-2009
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
10-Jun-2009
Due Date
15-Aug-2009
Completion Date
16-Jul-2009

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 60749-20-1:2009
01-september-2009
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2EGHODYDSDNLUDQMHR]QDþHYDQMHLQSRãLOMDQMHHOHPHQWRY]DSRYUãLQVNRPRQWDåR
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Semiconductor devices - Mechanical and climatic test methods - Part 20-1: Handling,
packing, labelling and shipping of surface mount devices sensitive to the combined effect
of moisture and soldering heat (IEC 60749-20-1:2009)
Halbleiterbauelemente - Mechanische und klimatische Prüfverfahren - Teil 20-1:
Handhabung, Verpackung, Kennzeichnung und Transport oberflächenmontierbarer
Bauelemente, die empfindlich gegen die Kombination von Feuchte und Lötwärme sind
(IEC 60749-20-1:2009)
Dispositifs à semiconducteurs - Méthodes d'essais mécaniques et climatiques - Partie 20
-1: Manipulation, emballage, étiquetage et transport des composants pour montage en
surface sensibles à l'effet combiné de l'humidité et de la chaleur de brasage (CEI 60749-
20-1:2009)
Ta slovenski standard je istoveten z: EN 60749-20-1:2009
ICS:
31.080.01 Polprevodniški elementi Semiconductor devices in
(naprave) na splošno general
SIST EN 60749-20-1:2009 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST EN 60749-20-1:2009

---------------------- Page: 2 ----------------------

SIST EN 60749-20-1:2009

EUROPEAN STANDARD
EN 60749-20-1

NORME EUROPÉENNE
June 2009
EUROPÄISCHE NORM

ICS 31.080.01


English version


Semiconductor devices -
Mechanical and climatic test methods -
Part 20-1: Handling, packing, labelling and shipping
of surface-mount devices sensitive to the combined effect
of moisture and soldering heat
(IEC 60749-20-1:2009)


Dispositifs à semiconducteurs -  Halbleiterbauelemente -
Méthodes d'essais mécaniques Mechanische und klimatische
et climatiques - Prüfverfahren -
Partie 20-1: Manipulation, emballage, Teil 20-1: Handhabung, Verpackung,
étiquetage et transport des composants Kennzeichnung und Transport
pour montage en surface sensibles oberflächenmontierbarer Bauelemente,
à l'effet combiné de l'humidité die empfindlich gegen die Kombination
et de la chaleur de brasage von Feuchte und Lötwärme sind
(CEI 60749-20-1:2009) (IEC 60749-20-1:2009)


This European Standard was approved by CENELEC on 2009-05-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: Avenue Marnix 17, B - 1000 Brussels


© 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60749-20-1:2009 E

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SIST EN 60749-20-1:2009
EN 60749-20-1:2009 - 2 -
Foreword
The text of document 47/2010/FDIS, future edition 1 of IEC 60749-20-1, prepared by IEC TC 47,
Semiconductor devices, was submitted to the IEC-CENELEC parallel vote and was approved by
CENELEC as EN 60749-20-1 on 2009-05-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2010-02-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2012-05-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60749-20-1:2009 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60749-37 NOTE  Harmonized as EN 60749-37:2008 (not modified).
IEC 60749-39 NOTE  Harmonized as EN 60749-39:2006 (not modified).
__________

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SIST EN 60749-20-1:2009
- 3 - EN 60749-20-1:2009
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.

Publication Year Title EN/HD Year

1) 2)
IEC 60749-20 - Semiconductor devices - Mechanical and EN 60749-20 200X
climatic test methods -
Part 20: Resistance of plastic encapsulated
SMDs to the combined effect of moisture and
soldering heat


1) 3)
IEC 60749-30 - Semiconductor devices - Mechanical and EN 60749-30 2005
climatic test methods -
Part 30: Preconditioning of non-hermetic
surface mount devices prior to reliability
testing




1)
Undated reference.
2)
To be ratified.
3)
Valid edition at date of issue.

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SIST EN 60749-20-1:2009

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SIST EN 60749-20-1:2009
IEC 60749-20-1
®
Edition 1.0 2009-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Semiconductor devices – Mechanical and climatic test methods –
Part 20-1: Handling, packing, labelling and shipping of surface-mount devices
sensitive to the combined effect of moisture and soldering heat

Dispositifs à semiconducteurs – Méthodes d'essais mécaniques et climatiques –
Partie 20-1: Manipulation, emballage, étiquetage et transport des composants
pour montage en surface sensibles à l'effet combiné de l'humidité et de la
chaleur de brasage

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
V
CODE PRIX
ICS 31.080.01 ISBN 2-8318-1036-6
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 7 ----------------------

SIST EN 60749-20-1:2009
– 2 – 60749-20-1 © IEC:2009
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references .7
3 Terms and definitions .7
4 General applicability and reliability considerations.9
4.1 Assembly processes.9
4.1.1 Mass reflow .9
4.1.2 Localized heating .9
4.1.3 Socketed components .9
4.1.4 Point-to-point soldering .9
4.2 Reliability .9
5 Dry packing .10
5.1 Requirements.10
5.2 Drying of SMDs and carrier materials before being sealed in MBBs.10
5.2.1 Drying requirements - level A2.10
5.2.2 Drying requirements - levels B2a to B5a.10
5.2.3 Drying requirements - carrier materials .10
5.2.4 Drying requirements - other .11
5.2.5 Excess time between bake and bag.11
5.3 Dry pack.11
5.3.1 Description .11
5.3.2 Materials .11
5.3.3 Labels .13
5.3.4 Shelf life .14
6 Drying .14
6.1 Drying options .14
6.2 Post exposure to factory ambient .16
6.2.1 Floor life clock .16
6.2.2 Any duration exposure.16
6.2.3 Short duration exposure .16
6.3 General considerations for baking .17
6.3.1 High-temperature carriers.17
6.3.2 Low-temperature carriers.17
6.3.3 Paper and plastic container items .17
6.3.4 Bakeout times.17
6.3.5 ESD protection .17
6.3.6 Reuse of carriers .17
6.3.7 Solderability limitations.17
7 Use .18
7.1 Floor life clock start .18
7.2 Incoming bag inspection.18
7.2.1 Upon receipt.18
7.2.2 Component inspection .18
7.3 Floor life.18
7.4 Safe storage.19

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SIST EN 60749-20-1:2009
60749-20-1 © IEC:2009 – 3 –
7.4.1 Safe storage categories.19
7.4.2 Dry pack.19
7.4.3 Dry atmosphere cabinet.19
7.5 Reflow.19
7.5.1 Reflow categories .19
7.5.2 Opened MBB .19
7.5.3 Reflow temperature extremes .19
7.5.4 Additional thermal profile parameters .20
7.5.5 Multiple reflow passes .20
7.5.6 Maximum reflow passes .20
7.6 Drying indicators .20
7.6.1 Drying requirements .20
7.6.2 Excess humidity in the dry pack.20
7.6.3 Floor life or ambient temperature/humidity exceeded.21
7.6.4 Level B6 SMDs.21
Annex A (normative) Symbol and labels for moisture-sensitive devices.22
Annex B (informative) Board rework.27
Annex C (informative) Derating due to factory environmental conditions .28
Bibliography.31

Figure 1 – Typical dry pack configuration for moisture-sensitive SMDs in shipping
tubes .11
Figure 2a – Example humidity indicator card for level A2 .13
Figure 2b – Example humidity indicator card for levels B2a to B5a .13
Figure 2 – Example humidity indicator cards .13
Figure A.1 – Moisture-sensitive symbol (example) .22
Figure A.2 – MSID label (example) .22
Figure A.3 – Information label for level A1 or B1 (example).23
Figure A.4 – Moisture-sensitive caution label for level A2 (example) .24
Figure A.5 – Moisture-sensitive caution label for levels B2-B5a (example) .25
Figure A.6 – Moisture-sensitive caution label for level B6 (example) .26

Table 1 – Dry packing requirements.10
Table 2 – Reference conditions for drying mounted or unmounted SMDs (user bake:
floor life begins counting at time = 0 after bake).14
Table 3 – Default baking times used prior to dry-pack that were exposed to conditions
16
≤60 % RH (supplier bake: MET = 24 h) .
Table 4 – Moisture classification level and floor life .18
Table C.1 – Recommended equivalent total floor life (days) for level A2 at 20 °C, 25 °C,
30 °C and 35 °C for ICs with Novolac, biphenyl and multifunctional epoxies (reflow at
same temperature at which component was classified) .28
Table C.2 – Recommended equivalent total floor life (days) for levels B2a to B5a at
20 °C, 25 °C, 30 °C and 35 °C for ICs with Novolac, biphenyl and multifunctional
epoxies (reflow at same temperature at which component was classified).29

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SIST EN 60749-20-1:2009
– 4 – 60749-20-1 © IEC:2009
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –

Part 20-1: Handling, packing, labelling and shipping of surface-mount
devices sensitive to the combined effect of moisture and soldering heat


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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 60749-20-1 has been prepared by IEC technical committee 47:
Semiconductor devices.
This standard cancels and replaces IEC/PAS 62168 and IEC/PAS 62169 published in 2000.
IEC/PAS 62169 was based on a Joint (IPC/JEDEC) Industry Standard. This first edition of
IEC 60749-20-1 constitutes a technical revision.

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SIST EN 60749-20-1:2009
60749-20-1 © IEC:2009 – 5 –
The text of this standard is based on the following documents:
FDIS Report on voting
47/2010/FDIS 47/2013/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 60749 series, under the general title Semiconductor devices –
Mechanical and climatic test methods, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

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SIST EN 60749-20-1:2009
– 6 – 60749-20-1 © IEC:2009
INTRODUCTION
The advent of surface-mount devices (SMDs) introduced a new class of quality and reliability
concerns regarding package damage ‘‘cracks and delamination’’ from the solder reflow
process. This document describes the standardized levels of floor life exposure for
moisture/reflow-sensitive SMDs along with the handling, packing and shipping requirements
necessary to avoid moisture/reflow-related failures. IEC 60749-20 defines the classification
procedure and Annex A of this document defines the labelling requirements.
Moisture from atmospheric humidity enters permeable packaging materials by diffusion.
Assembly processes used to solder SMDs to printed circuit boards (PCBs) expose the entire
package body to temperatures higher than 200 °C. During solder reflow, the combination of
rapid moisture expansion, materials mismatch, and material interface degradation can result
in package cracking and/or delamination of critical interfaces within the package.
The solder reflow processes of concern are convection, convection/IR, infrared (IR), vapour
phase (VPR) and hot air rework tools. The use of assembly processes that immerse the
component body in molten solder are not recommended for most SMDs.
1
This first edition of IEC 60749-20-1 is based principally on IPC/JEDEC J-STD-033 and the
permission to use this standard is gratefully acknowledged. It is also based on contributing
documents from various national committees.
___________
1
 Refer to Bibliography.

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SIST EN 60749-20-1:2009
60749-20-1 © IEC:2009 – 7 –
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –

Part 20-1: Handling, packing, labelling and shipping of surface-mount
devices sensitive to the combined effect of moisture and soldering heat



1 Scope
This part of IEC 60749 applies to all non-hermetic SMD packages which are subjected to
reflow solder processes and which are exposed to the ambient air.
The purpose of this document is to provide SMD manufacturers and users with standardized
methods for handling, packing, shipping, and use of moisture/reflow sensitive SMDs which
have been classified to the levels defined in IEC 60749-20. These methods are provided to
avoid damage from moisture absorption and exposure to solder reflow temperatures that can
result in yield and reliability degradation. By using these procedures, safe and damage-free
reflow can be achieved, with the dry packing process, providing a minimum shelf life
capability in sealed dry-bags from the seal date.
Two test conditions, method A and method B, are specified in the soldering heat test of
IEC 60749-20. For method A, moisture soak conditions are specified on the assumption that
moisture content inside the moisture barrier bag is less than 30 % RH. For method B,
moisture soaking conditions are specified on the assumption that manufacturer’s exposure
time (MET) does not exceed 24 h and the moisture content inside the moisture barrier bag is
less than 10 % RH. In an actual handling environment, SMDs tested by method A are
permitted to absorb moisture up to 30 % RH, and SMDs tested by method B are permitted to
absorb moisture up to 10 % RH. This standard specifies the handling conditions for SMDs
subjected to the above test conditions.
NOTE Hermetic SMD packages are not moisture sensitive and do not require moisture precautionary handling.
2 Normative references
The following referenced documents are indispensable for the application 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 60749-20, Semiconductor devices – Mechanical and climatic test methods – Part 20:
Resistance of plastic-encapsulated SMDs to the combined effect of moisture and soldering
heat
IEC 60749-30, Semiconductor devices – Mechanical and climatic test methods – Part 30:
Preconditioning of non-hermetic surface mount devices prior to reliability testing
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
active desiccant
desiccant that is either fresh (new) or has been baked according to the manufacturer’s
recommendations to renew it to original specifications

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SIST EN 60749-20-1:2009
– 8 – 60749-20-1 © IEC:2009
3.2
bar code label
a label that gives information in a code consisting of parallel bars and spaces, each of various
specific widths
NOTE For the purposes of this standard, the bar code label is on the lowest level shipping container and includes
information that describes the product, e.g., part number, quantity, lot information, supplier identification, and
moisture-sensitivity level etc.
3.3
mass reflow
reflow of a number of components with simultaneous attachment by an infrared (IR),
convection/IR, convection, or vapour phase reflow (VPR) process
3.4
carrier
container that directly holds components such as a tray, tube, or tape and reel
3.5
desiccant
absorbent material used to maintain a low relative humidity
3.6
floor life
allowable time period for a moisture-sensitive device, after removal from a moisture barrier
bag, dry storage or dry bake and before the solder reflow process
3.7
humidity indicator card
HIC
card on which a moisture-sensitive chemical is applied in such a way that it will make a
significant, perceptible change in colour (hue), typically from blue (dry) to pink (wet) when the
indicated relative humidity is exceeded
NOTE The HIC is packed inside the moisture-barrier bag, along with a desiccant, to aid in determining the level of
moisture to which the moisture-sensitive devices have been subjected.
3.8
manufacturer’s exposure time
MET
maximum time after bake that the component manufacturer requires to process components
prior to bag seal; it also includes the maximum time allowed at the distributor for having the
bag open to split out smaller shipments
3.9
moisture barrier bag
MBB
bag designed to restrict the transmission of water vapour and used to pack moisture-sensitive
devices
3.10
rework
the removal of a component for scrap, reuse, or failure analysis; the replacement of an
attached component; or the heating and repositioning of a previously attached component
3.11
shelf-life
maximum storage period for a dry-packed moisture-sensitive device in an unopened moisture
barrier bag (MBB) to avoid exceeding the specified interior bag ambient humidity

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SIST EN 60749-20-1:2009
60749-20-1 © IEC:2009 – 9 –
3.12
surface-mount device
SMD
plastic-encapsulated surface-mount devices made with moisture-permeable materials
NOTE For the purposes of this standard, the term SMD is limited as indicated in the definition.
3.13
solder reflow
a solder attachment process in which previously applied solder or solder paste is melted to
attach a component to the printed circuit board
3.14
water vapour transmission rate
WVTR
measure of the permeability of plastic film or metallized plastic film material to moisture
4 General applicability and reliability considerations
4.1 Assembly processes
4.1.1 Mass reflow
This standard applies to mass solder reflow assembly by convection, convection/IR, infrared
(IR), and vapour phase (VPR), processes.
...

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