SIST EN 60749-20:2004
(Main)Semiconductor devices - Mechanical and climatic test methods -- Part 20: Resistance of plastic-encapsulated SMDs to the combined effect of moisture and soldering heat
Semiconductor devices - Mechanical and climatic test methods -- Part 20: Resistance of plastic-encapsulated SMDs to the combined effect of moisture and soldering heat
Applies to semiconductor devices (discrete devices and integrated circuits) - and provides a means of assessing the resistance to soldering heat of plastic-encapsulated surface mount devices.
Halbleiterbauelemente - Mechanische und klimatische Prüfverfahren -- Teil 20: Beständigkeit kunststoffverkappter oberflächenmontierbarer Bauelemente (SMD) gegenüber der kombinierten Beanspruchung von Feuchte und Lötwärme
Dispositifs à semiconducteurs - Méthodes d'essais mécaniques et climatiques -- Partie 20: Résistance des CMS à boîtier plastique à l'effet combiné de l'humidité et de la chaleur de soudage
Applicable aux dispositifs à semiconducteurs (dispo-sitifs discrets et circuits intégrés), cette méthode d'essai fournit des moyens d'évaluer la résistance à la chaleur de soudage des composants plastiques à montage en surface.
Semiconductor devices - Mechanical and climatic test methods - Part 20: Resistance of plastic- encapsulated SMDs to the combined effect of moisture and soldering heat (IEC 60749-20:2002)
General Information
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Standards Content (Sample)
SLOVENSKI SIST EN 60749-20:2004
STANDARD
julij 2004
Semiconductor devices - Mechanical and climatic test methods - Part 20:
Resistance of plastic- encapsulated SMDs to the combined effect of moisture and
soldering heat (IEC 60749-20:2002)
ICS 31.080.01 Referenčna številka
SIST EN 60749-20:2004(en)
© Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno
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EUROPEAN STANDARD EN 60749-20
NORME EUROPÉENNE
EUROPÄISCHE NORM June 2003
ICS 31.080.01
English version
Semiconductor devices -
Mechanical and climatic test methods
Part 20: Resistance of plastic-encapsulated SMDs to the combined effect
of moisture and soldering heat
(IEC 60749-20:2002)
Dispositifs à semiconducteurs - Halbleiterbauelemente -
Méthodes d'essais mécaniques Mechanische und klimatische Prüfverfahren
et climatiques Teil 20: Beständigkeit kunststoffverkappter
Partie 20: Résistance des CMS à boîtier oberflächenmontierbarer Bauelemente
plastique à l'effet combiné de l'humidité (SMD) gegenüber der kombinierten
et de la chaleur de soudage Beanspruchung von Feuchte und Lötwärme
(CEI 60749-20:2002) (IEC 60749-20:2002)
This European Standard was approved by CENELEC on 2002-09-24. 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, Czech Republic,
Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta,
Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2003 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60749-20:2003 E
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EN 60749-20:2003 - 2 -
Foreword
The text of the International Standard IEC 60749-20:2002 was approved by CENELEC as
EN 60749-20 on 2002-09-24.
The text of this International Standard was reproduced from IEC 60749:1996, chapter 2, subclause 2.3
without change. Therefore, it has not been submitted to vote a second time and is still based on
document 47/1574/FDIS.
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) 2004-01-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2005-10-01
Each test method governed by this standard and which is part of the series is a stand-alone
document, numbered EN 60749-2, EN 60749-3, etc. The numbering of these test methods is
sequential, and there is no relationship between the number and the test method (i.e. no grouping of
test methods). The list of these tests will be available in the CENELEC internet site and in the
catalogue.
Updating of any of the individual test methods is independent of any other part.
Annexes designated "normative" are part of the body of the standard.
In this standard, annex ZA is normative.
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60749-20:2002 was approved by CENELEC as a European
Standard without any modification.
__________
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- 3 - EN 60749-20:2003
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of any
of these publications apply to this European Standard only when incorporated in it by amendment or
revision. For undated references the latest edition of the publication referred to applies (including
amendments).
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)
IEC 60068-2-20 1979 Basic environmental testing procedures HD 323.2.20 S3 1988
Part 2: Tests - Test T: Soldering
2) 3)
IEC 60749-3 - Semiconductor devices - Mechanical EN 60749-3 2002
and climatic test methods
Part 3: External visual examination
1)
HD 323.2.20 S3 includes A2:1987 to IEC 60068-2-20:1979.
2)
Undated reference.
3)
Valid edition at date of issue.
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NORME CEI
INTERNATIONALE IEC
60749-20
INTERNATIONAL
Première édition
STANDARD
First edition
2002-09
Dispositifs à semiconducteurs –
Méthodes d'essais mécaniques et climatiques –
Partie 20:
Résistance des CMS à boîtier plastique
à l'effet combiné de l'humidité et de la
chaleur de soudage
Semiconductor devices –
Mechanical and climatic test methods –
Part 20:
Resistance of plastic-encapsulated SMDs
to the combined effect of moisture
and soldering heat
© IEC 2002 Droits de reproduction réservés ⎯ Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in any
utilisée sous quelque forme que ce soit et par aucun procédé, form or by any means, electronic or mechanical, including
électronique ou mécanique, y compris la photocopie et les photocopying and microfilm, without permission in writing from
microfilms, sans l'accord écrit de l'éditeur. the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
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Commission Electrotechnique Internationale PRICE CODE
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Pour prix, voir catalogue en vigueur
For price, see current catalogue
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60749-20 © IEC:2002 – 3 –
CONTENTS
FOREWORD . 5
INTRODUCTION .9
1 Scope and object .11
2 Normative references.11
3 General description.11
4 Test apparatus and materials.11
5 Procedure.13
6 Information to be given in the relevant specification.25
Annex A (normative) Methods of inspection by acoustic tomography.27
Annex B (informative) Details and descriptions of test method on resistance of
plastic-encapsulated SMDs to the combined effect of moisture and soldering heat.31
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60749-20 © IEC:2002 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –
Part 20: Resistance of plastic-encapsulated SMDs to
the combined effect of moisture and soldering heat
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60749-20 has been prepared by IEC technical committee 47:
Semiconductor devices.
The text of this test method is reproduced from IEC 60749 Ed.2, chapter 2, subclause 2.3
without change. It has therefore not been submitted to vote a second time and is still based
on the following documents:
FDIS Report on voting
47/1574/FDIS 47/1576/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 3.
Each test method governed by IEC 60749-1 and which is part of the series is a stand-alone
document, numbered IEC 60749-2, IEC 60749-3, etc. The numbering of these test methods is
sequential, and there is no relationship between the number and the test method (i.e. no
grouping of test methods). The list of these tests will be available in the IEC Internet site and
in the catalogue.
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60749-20 © IEC:2002 – 7 –
Updating of any of the individual test methods is independent of any other part.
The committee has decided that the contents of this publication will remain unchanged until
2007. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
The contents of the corrigendum of August 2003 have been included in this copy.
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60749-20 © IEC:2002 – 9 –
INTRODUCTION
Activity within IEC technical committee 47, working group 2, includes the generation,
coordination and review of climatic, electrical (of which only ESD, latch-up and electrical
conditions for life tests are considered), mechanical test methods, and associated inspection
techniques needed to assess the quality and reliability of the design and manufacture of
semiconductor productors and processes.
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60749-20 © IEC:2002 – 11 –
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –
Part 20: Resistance of plastic-encapsulated SMDs to
the combined effect of moisture and soldering heat
1 Scope and object
This part of IEC 60749 applies to semiconductor devices (discrete devices and integrated
circuits).
This test method provides a means of assessing the resistance to soldering heat of plastic-
encapsulated surface mount devices (SMDs). This test is destructive.
NOTE This test is identical to the test method contained in 2.3 of chapter 2 of IEC 60749 (1996), amendment 2,
apart from the addition of this clause and clause 2 and the subsequent renumbering.
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 60068-2-20:1979, Environmental testing – Part 2: Tests – Test T: Soldering
IEC 60749-3, Semiconductor devices − Mechanical and climatic test methods − Part 3:
External visual inspection
3 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. These problems are assessed. In this test method, 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.
4 Test apparatus and materials
a) Humidity chamber
The humidity chamber shall provide an environment complying with the temperature and
relative humidity defined in item c) of clause 5.
b) Reflow soldering apparatus
The infra-red convection, the convection and the vapour-phase reflow soldering apparatus
shall provide temperature profiles complying with the conditions of soldering heat defined
in items d)1) and d)2) of clause 5. The settings of the reflow soldering apparatus shall be
adjusted by temperature profiling of the top surface of the specimen while it is undergoing
the soldering heat process, measured as shown in figure 1.
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60749-20 © IEC:2002 – 13 –
Adhesive agent or thin tape
Thermocouple
Die
Lead pins
Resin
Holder
IEC 1746/01
NOTE The adhesive agent or thin tape should have good thermal conductivity.
Figure 1 – Method of measuring the temperature profile of a specimen
c) Holder
Unless otherwise detailed in the relevant specification, any board material, such as epoxy
fibreglass or polyimide, may be used for the holder. The specimen shall be placed on the
holder by the usual means and in a position as shown in figure 1. If the position of the
specimen, as shown in figure 1, necessitates changing the shape of terminations and
results in subsequent electrical measurement anomalies, a position that avoids changing
the shape of terminations may be chosen, and this shall be specified in the relevant
specification.
d) Wave-soldering apparatus
The wave-soldering apparatus shall comply with conditions given in item d)3) of clause 5.
Molten solder shall usually be flowed.
e) Solvent for vapour-phase reflow soldering
Perfluorocarbon (perfluoroisobutylene) shall be used.
f) Flux
Unless otherwise detailed in the relevant specification, the flux shall consist of 25 % by
weight of colophony in 75 % by weight of isopropyl alcohol, both as specified in appendix C
of IEC 60068-2-20.
g) Solder
Solder of composition as specified in appendix B of IEC 60068-2-20 shall be used.
5 Procedure
a) Initial measurements
1) Visual inspection
Visual inspection, as specified in IEC 60749-3, shall be performed before the test.
Special attention shall be paid to external cracks and swelling, which will be looked for
under a magnification of 40×.
2) Electrical measurement
Electrical testing shall be performed as required by the relevant specification.
3) Internal inspection by acoustic tomography
Unless otherwise detailed in the relevant specification, internal cracks and
delamination in the specimen shall be inspected by acoustic tomography in accordance
with annex A.
b) Drying
Unless otherwise detailed in the relevant specification, the specimen shall be baked at
125 °C ± 5 °C for at least 24 h.
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60749-20 © IEC:2002 – 15 –
c) Moisture soak
Unless otherwise detailed in the relevant specification, moisture soak conditions shall be
selected on the basis of the packing method of the specimen (see B.1.1). If baking the
specimen before soldering is detailed in the relevant specification, the specimen shall be
baked instead of being subject to moisture soak.
1) Moisture soak for dry-packed SMDs
Moisture soak conditions for dry-packed SMDs may be used as specified in method A,
table 1, or method B, table 2. Moisture soak conditioning for dry-packed SMDs
consists of two stages. The first stage of conditioning is intended to simulate
moisturizing SMDs before opening the dry pack/dry cabinet. The second stage of
conditioning is to simulate moisturizing SMDs during storage after opening the dry
pack for soldering (floor life). Moisture soak conditioning for dry-packed SMDs shall be
selected from method A or B. Method A shall be used when the relative humidity in the
dry pack or dry cabinet is specified by the manufacturer as being between 10 % and
30 %. Method B shall be used when the relative humidity in the dry pack or dry cabinet
is specified by the manufacturer as being below 10 %.
i) Method A
Unless otherwise detailed in the relevant specification, the first stage of
conditioning A1, as shown in table 1, shall be performed. Subsequently, the second
stage of conditioning A2, as shown in table 1, shall be performed within 4 h of
finishing the first stage of conditioning (see B.1.2.2).
Table 1 – Moisture soak conditions for dry-packed SMDs (method A)
Permissible storage
Moisture soak conditions in the dry Condition of
Condition
conditions pack and the dry floor life
cabinet
First-stage (85 ± 2) °C, (30 ± 5) % RH,
conditioning A1 <30 °C, 30 % RH, 1 year –
24
168 h
−0
Second-stage (30 ± 2) °C, (70 ± 5) % RH,
A2 – <30 °C, 70 % RH, 168 h
conditioning
24
168 h
−0
RH: Relative humidity.
NOTE 1 The first stage of conditioning represents storage conditions in the dry pack and the dry cabinet, as
well as increasing relative humidity in the dry pack, by repacking the SMDs at the distributor's facility and the
user's inspection facility. When condition A1 is applied, the SMDs must be packed into a moisture-proof bag with
IC trays and desiccants within a few weeks of drying. They may then be subjected to multiple temporary
openings of the moisture-proof bag (for several hours at a time). Repack and inspection of SMDs are possible
while the humidity indicator in the dry pack indicates less than 30 % RH since SMDs will recover the initial
condition of absorbed moisture within a few days of repacking. In this case, the moisture content measurement
of SMDs (see clause B.2 ) is not needed as a moisture control of the dry pack. A check of the moisture indicator
is sufficient for moisture control.
NOTE 2 When moisture soak of the first-stage conditioning does not result in saturation, the soak time
is extended to 336 h, because SMDs in a dry pack or dry cabinet will become saturated with moisture during
long-term storage. When the moisture soak of the first stage of conditioning reaches saturation, the soak time
is shortened.
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60749-20 © IEC:2002 – 17 –
ii) Method B
The condition of moisture soak conditioning shall be selected from table 2 in
accordance with the condition of the floor life detailed in the relevant specification
(see B.1.2.3 ).
Table 2 – Moisture soak conditions for dry-packed SMDs (method B)
Total conditions from baking
Condition Moisture soak conditions to dry packing and temporary Condition of floor life
opening of the dry pack
(30 ± 2) °C, (60 ± 5) % RH,
B1 <30 °C, 60 % RH, 24 h <30 °C, 60 % RH, 168 h
+24
192 h
−0
(30 ± 2) °C, (60 ± 5) % RH,
B2 <30 °C, 60 % RH, 24 h <30 °C, 60 % RH, 72 h
+24
96 h
−0
(30 ± 2) °C, (60 ± 5) % RH,
B3 <30 °C, 60 % RH, 24 h <30 °C, 60 % RH, 48 h
+24
72 h
−0
(30 ± 2) °C, (60 ± 5) % RH,
B4 <30 °C, 60 % RH, 24 h <30 °C, 60 % RH, 24 h
+24
48 h
−0
(30 ± 2) °C, (60 ± 5) % RH,
B5 – <30 °C, 60 % RH, 6 h
+24
6 h
−0
RH: Relative humidity.
NOTE 3 Moisture soak conditions from B1 to B4 consist of the first-stage conditioning (30 °C, 60 % RH, 24 h) and
the second-stage conditioning (floor life).
NOTE 4 Contents in the dry pack of SMDs, IC trays and other materials, should be fully dried just before packing
into the moisture-proof bag and the desiccant must be completely dry. This is because moist materials and
degraded desiccants give off water vapour, causing the relative humidity in the dry pack to exceed 10 %.
The relative humidity in the dry pack should be verified by the humidity indicator and the moisture content
measurement of the SMDs, as shown in clause B.2.
NOTE 5 Storage of SMDs in a dry cabinet instead of a dry pack is not permitted because very low relative
humidity cannot be obtained in a dry cabinet.
NOTE 6 The individual conditions of method B shall cover total storage condition from baking the SMDs to
soldering them, and this should include the duration time of room storage from baking the SMDs to packing them
into the dry pack, temporary opening of the dry pack and the floor life.
2) Conditions for non-dry-packed SMDs
The moisture soak condition shall be selected from table 3, in accordance with the
permissible limit of actual storage (see B.1.2.1 ).
Table 3 – Moisture soak conditions for non-dry-packed SMDs
Temperature Relative humidity Duration time Permissible limit on
Condition
°C % h actual storage
C 85 ± 2 85 ± 5 168 ± 24 <30 °C, 85 % RH
D 85 ± 2 60 ± 5 168 ± 24 <30 °C, 60 % RH
RH: Relative humidity.
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60749-20 © IEC:2002 – 19 –
d) Soldering heat
Unless otherwise detailed in the relevant specification, the specimen shall be subjected to
soldering heat within 4 h of finishing the moisture soak or baking. The method and
condition of soldering heat shall be selected from items d)1) to d)3) of this subclause
according to the relevant specification. Whichever method is chosen, the soldering heat
cycles shall be a minimum of one and a maximum of three. Unless otherwise detailed in
the relevant specification, one cycle of soldering heat shall be used. If more than one
cycle is selected, the specimen shall be cooled down to below 50 °C before the second,
and subsequent, soldering heat.
NOTE 7 If the specimen is not affected by moisture soak and drying, which takes place during room storage of
over 4 h, a storage time exceeding 4 h following the completion of moisture soak or the baking may be detailed in
the relevant specification.
1) Method of heating by infra-red convection or convection reflow soldering
i) Preparation
The specimen shall be put on the holder.
ii) Preheating
Unless otherwise specified in the relevant specification, the specimen shall be
preheated at a temperature from 100 °C to 160 °C for 1 min to 2 min in the reflow
soldering apparatus.
iii) Solder heating
Following preheating, the temperature of the specimen shall be raised to peak
temperature and then lowered to room temperature. The heating condition shall be
selected from table 4 in accordance with the relevant specification.
NOTE 8 If the SMDs are thick and large, condition I-B should be selected, since the temperature of thick and large
SMDs having a large heat capacitance will not reach 220 °C during actual reflow soldering (see B.3.1 ).
NOTE 9 Following preheating, the temperature of the specimen should follow the values as indicated in the profile
given in figures B.9 or B.10 .
Table 4 – Heating condition for infra-red convection reflow
and convection reflow soldering
Range of peak
Time
Condition temperature
s
°C
I-A 10 ± 1 235 to 240
I-B 10 ± 1 220 to 225
2) Method of heating by vapour-phase reflow soldering
i) Preparation
The specimen shall be put on the holder.
ii) Preheating
Unless otherwise specified in the relevant specification, the specimen shall be
preheated at a temperature from 100 °C to 160 °C for 1 min to 2 min in the vapour-
phase soldering apparatus.
iii) Solder heating
The temperature of the specimen shall be raised after preheating. When the
temperature of the specimen has reached 215 °C ± 5 °C, it shall be maintained
for 40 s ± 4 s as shown in table 5 (refer to B.3.2 ).
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60749-20 © IEC:2002 – 21 –
Table 5 – Heating condition for vapour-phase soldering
Temperature Time
Condition
°C s
II-A 215 ± 5 40 ± 4
3) Method of heating by wave-soldering
i) Preparation
The bottom surface of the specimen shall be fixed to the holder by an adhesive
agent specified in the relevant specification. Unless otherwise detailed in the
relevant specification, flux shall not be applied to the specimen and holder.
NOTE 10 If flux is applied, vaporization of solvent in the flux could affect the temperature rise of the specimen.
Flux should not, therefore, be applied to the body of the specimen and should only be applied to lead pins as
sparingly as possible.
NOTE 11 Where SMDs have a stand-off (height between the bottom of the SMD body and the bottom of the lead
pin) of less than 0,5 mm (except lower thermal resistance SMDs with a heat sink and whose body thickness
exceeds 2,0 mm), they should be tested by soldering heat of condition I-A. SMDs whose body thickness exceeds
3,0 mm are tested by soldering heat by condition I-B. Wave-soldering of conditions III-A and III-B should be omitted
because conditions I-A and I-B are more severe than conditions III-A and III-B for these SMDs (refer to B.3.3 ).
ii) Preheating
Unless otherwise detailed in the relevant specification, the specimen shall be
preheated at a temperature of 80 °C to 140 °C for 30 s to 60 s in the soldering
apparatus.
iii) Solder heating
Following preheating, the specimen and the holder shall be immersed into flowing
molten solder, as shown in figure 2. The immersion condition shall be selected from
table 6.
Flowing molten
Holder
solder
Direction
Specimen
Direction
IEC 1747/01 IEC 1748/01
Figure 2a – Start of immersion Figure 2b – End of immersion
Figure 2 – Heating by wave-soldering
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60749-20 © IEC:2002 – 23 –
Table 6 – Immersion conditions for wave-soldering
Temperature of solder Immersing time Actual soldering
Condition
°C s method
III-A 260 ± 5 5 ± 1 Single-wave
III-B 260 ± 5 10 ± 1 Double-wave
iv) Cleaning
If the flux is applied, it shall be removed by a cleaning method detailed in the
relevant specification.
e) Recovery
If recovery is detailed in the relevant specification, the specimen shall be stored under
standard atmospheric conditions for the time given in the specification.
NOTE 12 Wave-soldering is not commonly available to the semiconductor manufacturer. Where the manufacturer
does not have access to such equipment, the method should be specified only by agreement between the
manufacturer and the customer.
f) Final measurements
1) Visual inspection, as specified in IEC 60749-3, shall be performed after the test.
Special attention shall be paid to external cracks and swelling which will be looked for
under a magnification of 40×.
2) Electrical measurement
Electrical testing shall be performed as required by the relevant specification.
3) Internal inspection by acoustic tomography
Unless otherwise specified in the relevant specification, internal cracks and
delamination in the specimen shall be inspected by acoustic tomography in accordance
with annex A.
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60749-20 © IEC:2002 – 25 –
6 Information to be given in the relevant specification
Clause
4
a) Material of holder item c)
b) Position of specimen on the holder item c)
c) Composition of flux item f)
d) Number of test specimens 5
e) Item and failure criteria for initial measurement item a)
f)Preconditioning item b)
g) Method of moisture soak item c)
h) Conditions of drying item b)
i) Baking conditions instead of the moisture soak item c)
j) Method of moisture soak for dry-packed SMDs item c)1)
k) Period between the stages of moisture soak conditioning item c)1)i)
l) Conditions of first-stage and second-stage conditioning
and whether another condition is needed item c)1)i)
m) Soak time of the first-stage conditioning if 168 h of soak time item c)1)i)
is insufficient
n) Moisture soak conditions for SMDs stored in completely item c)1)ii)
dried dry pack
o) Moisture soak conditions for non-dry-packed SMDs item c)2)
p) Period between finish of moisture soak and soldering heat item d)
q) Method and condition of soldering heat item d)
r) Number of cycles of soldering heat item d)
s) Preheat conditions for infra-red convection and convection item d)1)
reflow soldering
t) Heating conditions for infra-red convectio
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