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 60749-20-1:2019 is available as IEC 60749-20-1:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 60749-20-1:2019 applies to all devices subjected to bulk solder reflow processes during PCB assembly, including plastic encapsulated packages, process sensitive devices, and other moisture-sensitive devices made with moisture-permeable materials (epoxies, silicones, etc.) that 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 that 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. This edition includes the following significant technical changes with respect to the previous edition:
- updates to subclauses to better align the test method with IPC/JEDEC J-STD-033C, including new sections on aqueous cleaning and dry pack precautions;
- addition of two annexes on colorimetric testing of HIC (humidity indicator card) and derivation of bake tables.

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

IEC 60749-20-1:2019 est disponible sous forme de IEC 60749-20-1:2019 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.
L'IEC 60749-20-1:2019 s'applique à tous les dispositifs soumis à des procédés de brasage par refusion en masse lors de l'assemblage de la PCB, comprenant les boîtiers plastiques, les dispositifs sensibles aux procédés et les autres dispositifs sensibles à l'humidité fabriqués dans des matériaux perméables à l'humidité (époxydes, silicones, etc.), qui sont exposés à l'air ambiant. L'objet du présent 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 l'IEC 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 sachets scellés avec dessiccant à compter de la date de scellement. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- mises à jour de certains paragraphes pour mieux aligner la méthode d'essai avec le document IPC/JEDEC J-STD-033C, comprenant de nouvelles sections sur le nettoyage aqueux et les précautions applicables aux emballages avec dessiccant;
- ajout de deux annexes sur les essais colorimétriques des cartes indicatrices d'humidité (HIC) et la détermination des tableaux d'étuvage.

General Information

Status
Published
Publication Date
25-Jun-2019
Technical Committee
Current Stage
PPUB - Publication issued
Completion Date
26-Jun-2019
Ref Project

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IEC 60749-20-1:2019 - 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
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IEC 60749-20-1
Edition 2.0 2019-06
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
IEC 60749-20-1:2019-06(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60749-20-1
Edition 2.0 2019-06
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
INTERNATIONALE
ICS 31.080.01 ISBN 978-2-8322-7043-1

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
---------------------- Page: 3 ----------------------
– 2 – IEC 60749-20-1:2019 © IEC:2019
CONTENTS

FOREWORD ........................................................................................................................... 5

INTRODUCTION ..................................................................................................................... 7

1 Scope .............................................................................................................................. 8

2 Normative references ...................................................................................................... 8

3 Terms and definitions ...................................................................................................... 8

4 General applicability and reliability considerations ......................................................... 10

4.1 Assembly processes ............................................................................................. 10

4.1.1 Mass reflow ................................................................................................... 10

4.1.2 Localized heating........................................................................................... 10

4.1.3 Socketed components ................................................................................... 10

4.1.4 Point-to-point soldering .................................................................................. 10

4.1.5 Aqueous cleaning .......................................................................................... 11

4.2 Reliability .............................................................................................................. 11

5 Dry packing ................................................................................................................... 11

5.1 Requirements ....................................................................................................... 11

5.2 Drying of SMDs and carrier materials before being sealed in MBBs ...................... 11

5.2.1 Drying requirements – level A2 ...................................................................... 11

5.2.2 Drying requirements – levels B2a to B5a ....................................................... 12

5.2.3 Drying requirements – carrier materials ......................................................... 12

5.2.4 Drying requirements – other .......................................................................... 12

5.2.5 Excess time between bake and bag ............................................................... 12

5.3 Dry pack ............................................................................................................... 12

5.3.1 Description .................................................................................................... 12

5.3.2 Materials ....................................................................................................... 13

5.3.3 Labels ........................................................................................................... 16

5.3.4 Moisture barrier bag sealing .......................................................................... 16

5.3.5 Dry pack precautions ..................................................................................... 16

5.3.6 Shelf life ........................................................................................................ 16

6 Drying............................................................................................................................ 17

6.1 Drying options ....................................................................................................... 17

6.2 Post exposure to factory ambient .......................................................................... 20

6.2.1 Floor life clock ............................................................................................... 20

6.2.2 Any duration exposure ................................................................................... 20

6.2.3 Short duration exposure ................................................................................ 20

6.3 General considerations for baking ......................................................................... 20

6.3.1 High-temperature carriers .............................................................................. 20

6.3.2 Low-temperature carriers ............................................................................... 20

6.3.3 Paper and plastic container items .................................................................. 21

6.3.4 Bakeout times ................................................................................................ 21

6.3.5 ESD protection .............................................................................................. 21

6.3.6 Reuse of carriers ........................................................................................... 21

6.3.7 Solderability limitations .................................................................................. 21

7 Use ............................................................................................................................... 21

7.1 Floor life clock start .............................................................................................. 21

7.2 Incoming bag inspection ....................................................................................... 21

---------------------- Page: 4 ----------------------
IEC 60749-20-1:2019 © IEC:2019 – 3 –

7.2.1 Upon receipt .................................................................................................. 21

7.2.2 Component inspection ................................................................................... 22

7.3 Floor life ............................................................................................................... 22

7.4 Safe storage ......................................................................................................... 22

7.4.1 Safe storage categories ................................................................................. 22

7.4.2 Dry pack ........................................................................................................ 22

7.4.3 Shelf life ........................................................................................................ 22

7.4.4 Dry atmosphere cabinet ................................................................................. 22

7.5 Reflow .................................................................................................................. 23

7.5.1 Reflow categories .......................................................................................... 23

7.5.2 Opened MBB ................................................................................................. 23

7.5.3 Reflow temperature extremes ........................................................................ 23

7.5.4 Additional thermal profile parameters............................................................. 23

7.5.5 Multiple reflow passes ................................................................................... 23

7.5.6 Maximum reflow passes ................................................................................. 24

7.6 Drying indicators ................................................................................................... 24

7.6.1 Drying requirements ...................................................................................... 24

7.6.2 Excess humidity in the dry pack ..................................................................... 24

7.6.3 Floor life or ambient temperature/humidity exceeded ..................................... 25

7.6.4 Level B6 SMDs .............................................................................................. 25

Annex A (normative) Symbol and labels for moisture-sensitive devices ................................ 26

A.1 Object ................................................................................................................... 26

A.2 Symbol and labels................................................................................................. 26

A.2.1 Moisture-sensitive symbol .............................................................................. 26

A.2.2 Moisture-sensitive identification (MSID) label ................................................ 26

A.2.3 Moisture-sensitive caution labels ................................................................... 26

Annex B (informative) Board rework ..................................................................................... 30

B.1 Component removal, rework and remount ............................................................. 30

B.1.1 Removal precautions ..................................................................................... 30

B.1.2 Removal for failure analysis ........................................................................... 30

B.1.3 Removal and remount .................................................................................... 30

B.2 Baking of populated boards................................................................................... 30

Annex C (normative) Test method for Humidity Indicator Card used with electronic

component packaging ........................................................................................................... 31

C.1 HIC testing method ............................................................................................... 31

C.2 Testing apparatus ................................................................................................. 31

C.3 Testing procedure ................................................................................................. 31

C.4 Data analysis ........................................................................................................ 32

Annex D (informative) Derivation of bake tables ................................................................... 33

Annex E (informative) Derating due to factory environmental conditions .............................. 35

Bibliography .......................................................................................................................... 39

Figure 1 – Typical dry pack configuration for moisture-sensitive SMDs in shipping

tubes .................................................................................................................................... 12

Figure 2 – Example humidity indicator cards ......................................................................... 15

Figure A.1 – Moisture-sensitive symbol (example) ................................................................ 26

Figure A.2 – MSID label (example) ....................................................................................... 26

Figure A.3 – Information label for level A1 or B1 (example) ................................................... 27

---------------------- Page: 5 ----------------------
– 4 – IEC 60749-20-1:2019 © IEC:2019

Figure A.4 – Moisture-sensitive caution label for level A2 (example) ..................................... 27

Figure A.5 – Moisture-sensitive caution label for levels B2-B5a (example) ............................ 28

Figure A.6 – Moisture-sensitive caution label for level B6 (example) ..................................... 29

Figure D.1 –Typical moisture concentration over time ........................................................... 33

Table 1 – Dry packing requirements ...................................................................................... 11

Table 2 –Typical HIC spot compliance .................................................................................. 15

Table 3 – Reference conditions for drying mounted or unmounted SMDs (user bake:

floor life begins counting at time = 0 after bake) – Level 2..................................................... 17

Table 4 – Reference conditions for drying mounted or unmounted SMDs (user bake:

floor life begins counting at time = 0 after bake) – Levels B2, B2a to B5a ............................. 18

Table 5 – Default baking times used prior to dry-pack that were exposed to conditions

≤60 % RH (supplier bake: MET = 24 h) ................................................................................. 19

Table 6 – Resetting or pausing the ‘floor life’ clock at user site ............................................. 19

Table 7 – Moisture classification level and floor life .............................................................. 22

Table C.1 – HIC spot compliance: ......................................................................................... 31

Table E.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) ......................................................... 36

Table E.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) ............................. 37

---------------------- Page: 6 ----------------------
IEC 60749-20-1:2019 © IEC:2019 – 5 –
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

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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.

This second edition cancels and replaces the first edition published in 2009. This edition

constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous

edition:

a) updates to subclauses to better align the test method with IPC/JEDEC J-STD-033C,

including new sections on aqueous cleaning and dry pack precautions;

b) addition of two annexes on colorimetric testing of HIC (humidity indicator card) and

derivation of bake tables.
---------------------- Page: 7 ----------------------
– 6 – IEC 60749-20-1:2019 © IEC:2019
The text of this standard is based on the following documents:
FDIS Report on voting
47/2565/FDIS 47/2579/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 parts in the IEC 60749 series, published 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.
---------------------- Page: 8 ----------------------
IEC 60749-20-1:2019 © IEC:2019 – 7 –
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.

Typical solder reflow processes of concern for all devices are infrared (IR), convection/IR,

convection, vapour phase reflow (VPR), hot air rework tools, and wave solder, including full

immersion.

Non-semiconductor devices can exhibit additional process sensitivities beyond moisture

sensitivity such as thermal sensitivity, flux sensitivity, or cleaning process sensitivity.

---------------------- Page: 9 ----------------------
– 8 – IEC 60749-20-1:2019 © IEC:2019
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 devices subjected to bulk solder reflow processes during

PCB assembly, including plastic encapsulated packages, process sensitive devices, and other

moisture-sensitive devices made with moisture-permeable materials (epoxies, silicones, etc.)

that 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 that 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 document 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 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 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.

ISO and IEC maintain terminological databases for use in standardization at the following

addresses:
---------------------- Page: 10 ----------------------
IEC 60749-20-1:2019 © IEC:2019 – 9 –
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
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
3.2
bar code label
label that gives information in a code c
...

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