Semiconductor devices - Mechanical and climatic test methods - Part 30: Preconditioning of non-hermetic surface mount devices prior to reliability testing

IEC 60749-30:2020 is available as IEC 60749-30:2020 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 60749-30:2020 establishes a standard procedure for determining the preconditioning of non-hermetic surface mount devices (SMDs) prior to reliability testing.
The test method defines the preconditioning flow for non-hermetic solid-state SMDs representative of a typical industry multiple solder reflow operation.
These SMDs are subjected to the appropriate preconditioning sequence described in this document prior to being submitted to specific in-house reliability testing (qualification and/or reliability monitoring) in order to evaluate long term reliability (impacted by soldering stress). This edition includes the following significant technical changes with respect to the previous edition:
- inclusion of new Clause 3;
- expansion of 6.7 on solder reflow;
- inclusion of explanatory notes and clarifications.

Dispositifs à semiconducteurs - Méthodes d'essais mécaniques et climatiques - Partie 30: Préconditionnement des composants pour montage en surface non hermétiques avant les essais de fiabilité

IEC 60749-30:2020 est disponible sous forme de IEC 60749-30:2020 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.
L’IEC 60749-30:2020 établit une procédure normalisée de détermination du préconditionnement pour les composants pour montage en surface (CMS) non hermétiques avant les essais de fiabilité. Cette méthode d’essai définit une refusion de préconditionnement pour les CMS à l’état solide non hermétiques représentative d’une opération de refusion de soudure multiple industrielle type. Les CMS sont soumis à la séquence de préconditionnement appropriée décrite dans le présent document avant d’être soumis aux essais de fiabilité sur place spécifiques (qualification et/ou surveillance de la fiabilité) pour évaluer la fiabilité à long terme (qui pourrait être affectée par la refusion de soudure). Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- ajout du nouvel Article 3;
- extension de 6.7 concernant la refusion de soudure;
- inclusion de notes explicatives et de clarifications.

General Information

Status
Published
Publication Date
16-Aug-2020
Technical Committee
Current Stage
PPUB - Publication issued
Completion Date
17-Aug-2020
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IEC 60749-30
Edition 2.0 2020-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Semiconductor devices – Mechanical and climatic test methods –
Part 30: Preconditioning of non-hermetic surface mount devices prior to
reliability testing
Dispositifs à semiconducteurs – Méthodes d’essais mécaniques et climatiques –
Partie 30: Préconditionnement des composants pour montage en surface non
hermétiques avant les essais de fiabilité
IEC 60749-30:2020-08(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60749-30
Edition 2.0 2020-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Semiconductor devices – Mechanical and climatic test methods –
Part 30: Preconditioning of non-hermetic surface mount devices prior to
reliability testing
Dispositifs à semiconducteurs – Méthodes d’essais mécaniques et climatiques –
Partie 30: Préconditionnement des composants pour montage en surface non
hermétiques avant les essais de fiabilité
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.080.01 ISBN 978-2-8322-8669-2

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 60749-30:2020 © IEC 2020
CONTENTS

FOREWORD ........................................................................................................................... 3

1 Scope .............................................................................................................................. 5

2 Normative references ...................................................................................................... 5

3 Terms and definitions ...................................................................................................... 6

4 General description ......................................................................................................... 6

5 Test apparatus and materials .......................................................................................... 6

5.1 General ................................................................................................................... 6

5.2 Moisture chamber ................................................................................................... 7

5.3 Solder equipment .................................................................................................... 7

5.4 Optical microscope ................................................................................................. 7

5.5 Electrical test equipment ......................................................................................... 7

5.6 Drying (bake) oven.................................................................................................. 7

5.7 Temperature cycle chamber (optional) .................................................................... 7

6 Procedure ........................................................................................................................ 7

6.1 General ................................................................................................................... 7

6.2 Initial measurements ............................................................................................... 8

6.2.1 Electrical test ................................................................................................... 8

6.2.2 Visual inspection ............................................................................................. 8

6.3 Temperature cycling (optional) ................................................................................ 8

6.4 Drying (bake out) .................................................................................................... 8

6.5 Soak conditions for dry-packed SMDs ..................................................................... 8

6.5.1 General ........................................................................................................... 8

6.5.2 Method A for dry-packed SMDs in accordance with IEC 60749-20 ................... 8

6.5.3 Method B for dry-packed SMDs in accordance with IEC 60749‑20 ................... 8

6.6 Soak conditions for non-dry-packed SMDs in accordance with IEC 60749‑20 .......... 8

6.7 Solder reflow........................................................................................................... 9

6.7.1 Solder reflow procedure ................................................................................... 9

6.7.2 Solder attachment after reflow ......................................................................... 9

6.8 Flux application simulation (optional) .................................................................... 10

6.8.1 Flux application ............................................................................................. 10

6.8.2 Cleaning and drying after flux application ...................................................... 10

6.9 Final measurements .............................................................................................. 10

6.9.1 Electrical test ................................................................................................. 10

6.9.2 Visual inspection ........................................................................................... 10

6.10 Applicable reliability tests...................................................................................... 10

7 Summary ....................................................................................................................... 10

Table 1 – Preconditioning sequence flow – Method A (condition A2) in accordance with

IEC 60749-20 (dry-packed devices) ...................................................................................... 11

Table 2 – Preconditioning sequence flow – Method B (conditions B2 to B6) in

accordance with IEC 60749-20 (dry-packed devices) ............................................................ 11

Table 3 – Preconditioning sequence flow – Conditions A1 and B1 in accordance with

IEC 60749-20 (non dry-packed devices) ............................................................................... 12

---------------------- Page: 4 ----------------------
IEC 60749-30:2020 © IEC 2020 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –
Part 30: Preconditioning of non-hermetic surface
mount devices prior to reliability testing
FOREWORD

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

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

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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.

International Standard IEC 60749-30 has been prepared by IEC technical committee 47:

Semiconductor devices.
This second edition cancels and replaces the first edition published in 2005 and
Amendment 1:2011. This edition constitutes a technical revision.

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

edition:
a) inclusion of new Clause 3;
b) expansion of 6.7 on solder reflow;
c) inclusion of explanatory notes and clarifications.
---------------------- Page: 5 ----------------------
– 4 – IEC 60749-30:2020 © IEC 2020
The text of this International Standard is based on the following documents:
FDIS Report on voting
47/2633/FDIS 47/2644/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.

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 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.
---------------------- Page: 6 ----------------------
IEC 60749-30:2020 © IEC 2020 – 5 –
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –
Part 30: Preconditioning of non-hermetic surface
mount devices prior to reliability testing
1 Scope

This part of IEC 60749 establishes a standard procedure for determining the preconditioning

of non-hermetic surface mount devices (SMDs) prior to reliability testing.

The test method defines the preconditioning flow for non-hermetic solid-state SMDs

representative of a typical industry multiple solder reflow operation.

These SMDs are subjected to the appropriate preconditioning sequence described in this

document prior to being submitted to specific in-house reliability testing (qualification and/or

reliability monitoring) in order to evaluate long term reliability (impacted by soldering stress).

NOTE 1 Correlation of moisture-induced stress sensitivity conditions (or moisture sensitivity levels (MSL)) in

accordance with IEC 60749-20 and this document and the actual reflow conditions used are dependent upon

identical temperature measurement by both the semiconductor manufacturer and the board assembler. Therefore,

the temperature at the top of the package on the hottest moisture sensitive SMD during assembly is monitored to

ensure that it does not exceed the temperature at which the components are evaluated.

NOTE 2 For the purpose of this document, SMD is restricted to include only plastic-encapsulated SMDs and other

packages made with moisture-permeable materials.
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 60749-4, Semiconductor devices – Mechanical and climatic test methods – Part 4: Damp

heat, steady state, highly accelerated stress test (HAST)

IEC 60749-5, Semiconductor devices – Mechanical and climatic test methods – Part 5:

Steady-state temperature humidity bias life test

IEC 60749-11, Semiconductor devices – Mechanical and climatic test methods – Part 11:

Rapid change of temperature – Two-fluid-bath method

IEC 60749-20:2020, Semiconductor devices – Mechanical and climatic test methods – Part 20:

Resistance of plastic encapsulated SMDs to the combined effects of moisture and soldering

heat

IEC 60749-24, Semiconductor devices – Mechanical and climatic test methods – Part 24:

Accelerated moisture resistance – Unbiased HAST

IEC 60749-25:2003, Semiconductor devices – Mechanical and climatic test methods – Part 25:

Temperature cycling

IEC 60749-33, Semiconductor devices – Mechanical and climatic test methods – Part 33:

Accelerated moisture resistance – Unbiased autoclave.
---------------------- Page: 7 ----------------------
– 6 – IEC 60749-30:2020 © IEC 2020
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:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
dead-bug orientation
orientation of a package with the terminals facing upwards
3.2
floor life

allowable time period after removal of moisture-sensitive devices from a moisture-barrier bag

or dry bake and before the solder reflow process
3.3
live-bug orientation
orientation of a package when resting on its terminals
3.4
moisture-sensitivity level
MSL

rating indicating a device’s susceptibility to damage due to absorbed moisture when subjected

to reflow soldering
3.5
process sensitivity level
PSL

rating used to identify a component that is solder process sensitive and which cannot be used

in one or more of the base solder process conditions
3.6
solder reflow

solder attachment process in which previously applied solder or solder paste is melted to

attach a device to a printed circuit board
4 General description

Package cracking and electrical failure in plastic encapsulated SMDs can result when

soldering heat raises the vapour pressure of moisture which has been absorbed into SMDs

during storage. In this test method, such problems are assessed and SMDs are evaluated for

heat resistance after being soaked in an environment which simulates moisture being

absorbed while under storage in a warehouse or dry pack.
5 Test apparatus and materials
5.1 General
This test method requires, as a minimum, access to the following equipment.
---------------------- Page: 8 ----------------------
IEC 60749-30:2020 © IEC 2020 – 7 –
5.2 Moisture chamber

Moisture chamber(s) capable of operating at 85 °C/85 % RH (relative humidity), 85 °C/60 %

RH, 85 °C/30 % RH, 30 °C/70 % RH and 30 °C/60 % RH. Within the chamber working area,

temperature tolerance shall be ±2 °C and the RH tolerance shall be ±3 % RH. A chamber with

60 °C/60 % RH capability is optional for accelerated soak conditions.
5.3 Solder equipment
Solder equipment shall consist of the following.

a) 100 % convection reflow system capable of maintaining the reflow profiles required by this

document. This is the preferred equipment for solder reflow.

b) VPR (vapour phase reflow) chamber capable of operating the temperature profiles in

IEC 60749-20 with appropriate fluids. The chamber shall be capable of heating the

packages without collapsing the vapour blanket and of re-condensing the vapour to

minimize loss of the vapour phase soldering liquid. The vapour phase soldering fluid shall

vaporize at the appropriate temperature specified above.

c) Infrared (IR)/convection solder reflow equipment capable of maintaining the reflow profiles

required by this document. It is recommended that this equipment use the IR to heat the

air and not directly impinge upon the components under test.
d) Wave-solder equipment capable of maintaining the conditions in 6.4.4 of
IEC 60749-20:2020.

NOTE The moisture sensitivity condition (classification) test results are dependent upon the package body

temperature, rather than board or lead temperature. Convection and VPR are known to be more controllable and

repeatable than IR. When there are correlation problems between VPR, IR/convection, convection and wave solder

(if used), the convection results are considered as the standard.
5.4 Optical microscope
Optical microscope (40X for external visual examination).
5.5 Electrical test equipment

Electrical test equipment capable of performing room temperature DC and functional tests.

5.6 Drying (bake) oven
Oven for drying (bake) capable of operating at 125 °C.
5.7 Temperature cycle chamber (optional)

A temperature cycle chamber capable of operating as a minimum over a range of −40 °C to

−10
+10

+60 °C in accordance with IEC 60749-25. Acceptable alternative test conditions and

temperature tolerances are found in Table 1 of IEC 60749-25:2003. This equipment is only

required if 6.3 is used.
6 Procedure
6.1 General

It is recommended that a prior evaluation be run according to the moisture sensitivity levels

(MSLs) detailed in IEC 60749-20, using the appropriate method and similar devices, to

determine which preconditioning sequence is suitable, i.e. likely to pass. Other moisture

evaluation data can be consulted. However, the soak sequence in 6.5 needs to be consistent

with the floor life information in Table 1 and Table 2.
---------------------- Page: 9 ----------------------
– 8 – IEC 60749-30:2020 © IEC 2020

Reflow requirements are provided for both Pb-free and legacy SnPb conditions and are used

based on the intended end use of the SMD. The same package can have different MSL levels

depending on whether the SnPb or Pb-free reflow is used.
At all times the test parts shall be handled using appropriate ESD procedures.
6.2 Initial measurements
6.2.1 Electrical test

Perform an electrical DC test and functional test to verify that the devices meet the room

temperature data sheet specification. Replace any devices that fail to meet this requirement.

6.2.2 Visual inspection

Perform an external visual examination under 40X optical magnification to ensure that no

devices with external cracks or other damage are used in this test method. If mechanical

rejects are found, corrective action shall be implemented in the manufacturing process and a

new sample drawn from a product which has been processed with the corrective action.

6.3 Temperature cycling (optional)

Perform 5 cycles of temperature cycle from −40 °C (or lower) to +60 °C (or higher) to simulate

shipping conditions (the shippability option). This step is optional unless required by the

relevant specification.
6.4 Drying (bake out)

Bake the devices for at least 24 h minimum at (125 ± 5) °C. This step is intended to remove

moisture from the package so that it will be "dry".

NOTE 1 This time is modified if desorption data on the particular device being preconditioned shows that more or

less time is required to obtain a "dry" package.

NOTE 2 If the preconditioning sequence is being performed by the semiconductor manufacturer, steps 6.2.1,

6.2.2 and 6.4 are optional since they are at the supplier's own risk. If the preconditioning sequence is being

performed by the user, step 6.8 is optional.
6.5 Soak conditions for dry-packed SMDs
6.5.1 General

The following soak conditions shall apply. It is recommended that the soak be initiated within

2 h of bake.
6.5.2 Method A for dry-packed SMDs in accordance with IEC 60749-20

This test shall be carried out in accordance with 6.3.3.2, method A, of IEC 60749-20:2020 and

Table 1 of this document.
6.5.3 Method B for dry-packed SMDs in accordance with IEC 60749‑20

This shall be carried out in accordance with 6.3.3.3, method B, of IEC 60749-20:2020 and

Table 2 of this document.
6.6 Soak conditions for non-dry-packed SMDs in accordance with IEC 60749‑20

This shall be in accordance with 6.3.2 of IEC 60749-20:2019 and Table 3 of this document.

---------------------- Page: 10 ----------------------
IEC 60749-30:2020 © IEC 2020 – 9 –
6.7 Solder reflow
6.7.1 Solder reflow procedure

Not sooner than 15 min and not longer than 4 h after removal from the temperature/humidity

chamber, submit the devices to three cycles of the appropriate reflow conditions in

accordance with IEC 60749-20. All temperatures refer to the top surface of the package. The

sample parts shall be cooled sufficiently for at least 5 min (preferably back to room

temperature) between reflow cycles so that the reflow temperatures/times of the samples are

not affected on the subsequent reflow cycles.

Reflow practices shall be sufficient to ensure that all sample parts, in each reflow cycle, will

meet the appropriate reflow profile requirements of IEC 60749-20. SMDs intended for use in a

"Pb-free" assembly process shall be evaluated using the "Pb-free" reflow temperature whether

or not the SMD is Pb-free. If parts are reflowed in other than the normal assembly reflow

orientation (i.e. live-bug/dead-bug) the damage response shall be correlated.

The reflow oven shall be loaded with the same configuration or be verified to have an

equivalent thermal load when running preconditioning as was used to develop the reflow

profile. The reflow profiles in IEC 60749-20 are only for classification and preconditioning and

are not intended to specify board assembly profiles. Actual board assembly profiles shall be

developed based on specific process needs and board designs and shall not exceed the

parameters in IEC 60749-20.

If the timing between removal from the temperature/humidity chamber and initial reflow cannot

be met then the parts shall be rebaked and resoaked in accordance with 6.4 and 6.5.

NOTE 1 The three reflow cycles represent the following:

• Cycle 1 – the first pass of a double-sided, double-pass (DSDP) assembly reflow process.

• Cycle 2 – the second pass of a DSDP assembly reflow process.

• Cycle 3 – rework of a near neighbor on the assembly where the SMD being classified experiences reflow-like

temperatures.

NOTE 2 For SMDs that cannot be subjected to three reflows, only the number of reflows for which the SMD is

classified is performed.
6.7.2 Solder attachment after reflow

If reliability testing is to be performed in a second level configuration, one of the reflow cycles

can be used to attach the sample to the test board. If the board assembly is to be performed

at a later time then the sample, at the user's discretion, can be baked and vacuum sealed

until such time that it is solder attached to the test board or facsimile. The profile used to

attach the sample to the test board can be optimized for the soldering operation, but the other

two passes shall meet the profile requirements of IEC 60749-20.

Since the board attachment replicates a real life process with flux application, reflow and

cleaning, steps 6.8.1 and 6.8.2 are no longer necessary or mandated prior to submission to

reliability stress testing. Flux type shall be documented in accordance with Clause 7.

NOTE Bumped die devices are commonly soldered to test boards, due to the potential of inflicting handling

damage on the loose devices while performing the preconditioning, qualification stresse

...

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