prEN IEC 61760-4:2025

SLOVENSKI STANDARD
01-september-2025
Tehnologija površinske montaže - 4. del: Razvrščanje, pakiranje, etiketiranje in
ravnanje z napravami, občutljivimi na vlago
Surface mounting technology - Part 4: Classification, packaging, labelling and handling
of moisture sensitive devices
Oberflächenmontagetechnik - Teil 4: Genormtes Verfahren zur Klassifikation,
Verpackung, Kennzeichnung und Handhabung feuchteempfindlicher Bauteile
Technique du montage en surface - Partie 4: Classification, emballage, étiquetage et
manipulation des dispositifs sensibles à l’humidité
Ta slovenski standard je istoveten z: prEN IEC 61760-4:2025
ICS:
31.190 Sestavljeni elektronski Electronic component
elementi assemblies
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

91/2039/CDV
COMMITTEE DRAFT FOR VOTE (CDV)

PROJECT NUMBER:
IEC 61760-4 ED2
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2025-06-27 2025-09-19
SUPERSEDES DOCUMENTS:
91/1986/CD, 91/2030/CC
IEC TC 91 : ELECTRONICS ASSEMBLY TECHNOLOGY
SECRETARIAT: SECRETARY:
Japan Mr Osamu IKEDA
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):

TC 40,TC 47,TC 86
ASPECTS CONCERNED:
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
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Recipients of this document are invited to submit, with their comments, notification of any relevant “In Some
Countries” clauses to be included should this proposal proceed. Recipients are reminded that the CDV stage is
the final stage for submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).

TITLE:
Surface mounting technology - Part 4: Classification, packaging, labelling and handling of
moisture sensitive devices
PROPOSED STABILITY DATE: 2031
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IEC CDV 61760-4 © IEC 2025 2 91/2039/CDV

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IEC CDV 61760-4 © IEC 2025 3 91/2039/CDV

CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 General information . 10
4.1 Moisture sensitive devices . 10
4.2 moisture sensitivity level (3.2) (MSL) . 10
4.3 Relation to other environmental test methods (humidity tests) . 10
5 Assessment of moisture sensitivity . 11
5.1 Identification of non moisture sensitive devices . 11
5.2 Classification . 11
6 Test procedure . 12
6.1 General . 12
6.1.1 Structurally similar components . 12
6.1.2 Verification and validation tests . 12
6.1.3 Selection of applicable soak conditions and temperature profile . 12
6.2 Drying . 12
6.3 Moisture soak . 12
6.4 Temperature load. 13
6.4.1 Classification temperature profile . 13
6.4.2 Classification temperature profile for special devices . 14
6.4.3 Reflow . 14
6.5 Recovery . 15
6.6 Final measurements. 15
6.6.1 Requirements . 15
6.6.2 Visual inspection . 15
6.6.3 Electrical measurements . 15
6.6.4 Non-destructive inspection (if required) . 16
6.7 Classification . 16
6.8 Information to be given in the relevant specification . 16
7 Requirements to packaging and labelling . 16
7.1 Packaging process . 16
7.1.1 Drying of MSDs and carrier materials before being sealed in MBBs . 16
7.1.2 Evacuation and sealing . 17
7.2 Packaging material for dry pack . 17
7.2.1 Moisture barrier bag (MBB) . 17
7.2.2 Desiccant . 18
7.2.3 Humidity indicator . 20
7.3 Information to be given on labels . 20
8 Handling of moisture sensitive devices . 21
8.1 Storage . 21
8.1.1 Recommended storage conditions . 21
8.1.2 Shelf life . 21

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8.1.3 Floor life . 21
8.2 ESD . 22
8.3 Humidity indication. 22
8.3.1 Humidity indicator card (HIC) . 22
8.3.2 Moisture indicating desiccant . 22
8.4 Unpacking and re-packing. 22
9 Drying . 23
9.1 Drying options . 23
9.2 Methods . 24
9.2.1 General considerations for baking . 24
9.2.2 Bakeout times . 24
9.2.3 ESD protection . 25
9.2.4 Reuse of carriers . 25
9.2.5 Solderability limitations . 25
Annex A (informative) Moisture sensitivity of assemblies . 26
Annex B (informative) Mass/gain loss analysis . 27
Annex C (informative) Baking of devices . 28
C.1 Baking time and conditions . 28
C.2 Example of a baking process . 28
Annex D (normative) Moisture sensitivity labels . 29
D.1 Object . 29
D.2 Graphical symbols and labels . 29
D.2.1 Graphical symbol for moisture-sensitivity . 29
D.2.2 Moisture-sensitivity identification label (MSID) . 29
D.2.3 Moisture-sensitivity caution label (MSCL) . 29
Bibliography . 31

Figure 1 – Classification temperature profile . 13
Figure 2 – Examples of humidity indicator cards . 20
Figure C.1 – Baking process . 28
Figure D.1 – Standardized graphical symbol for use on equipment . 29
Figure D.2 – Alternative moisture sensitivity symbol (also in market use) . 29
Figure D.3 – MSID labels (examples) . 29

Table 1 – Moisture sensitivity levels . 11
Table 2 – Moisture soak conditions . 12
Table 3 – Parameters of the classification temperature profile . 13
Table 4 – Classification temperatures T . 14
c
Table 5 – MBB material properties . 18
Table 6 – Conditions for re-bake – Example for one type of plastic encapsulated
devices . 23
Table 7 – Conditions for baking prior to dry pack – Example for one type of plastic
encapsulated devices . 24

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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Surface mounting technology - Part 4: Classification, packaging, labelling
and handling of moisture sensitive devices ED2

FOREWORD
a) 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
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt
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Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two
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b) 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.
c) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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d) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
e) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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f) All users should ensure that they have the latest edition of this publication.
g) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
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h) 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.
i) 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 61760‑4 has been prepared by IEC technical committee 91:
Electronics assembly technology.
The text of this standard is based on the following documents
FDIS Report on voting
91/xxxx/FDIS 91/xxxx/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 61760, published under the general title Surface mounting
technology, can be found on the IEC website.

IEC CDV 61760-4 © IEC 2025 6 91/2039/CDV

The committee has decided that the contents of this publication will remain unchanged until the
stability date indicated on the IEC website 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.
The 'colour inside' logo on the cover page of this publication indicates that it contains
colours which are considered to be useful for the correct understanding of its contents.
Users should therefore print this document using a colour printer.

IEC CDV 61760-4 © IEC 2025 7 91/2039/CDV

INTRODUCTION
Due to the higher temperature profiles of reflow soldering processes using tin-silver-copper
alloys or other lead-free solder alloys with higher melting temperatures than Sn-Pb eutectic
solder, the sensitivity of components against soldering heat, when being exposed to moisture
before soldering, becomes an increasingly important factor.
The currently existing standards describing the moisture sensitivity classification of devices are
applicable for plastic encapsulated semiconductors and similar solid state packages (e.g.
IEC 60749‑20), but not for other types of components.
This part of IEC 61760 also extends the classification and packaging methods as described in
J-STD-020F [1]and J-STD-033 [2]. It is intended to be used for such type of components, where
J‑STD-020 and J‑STD-033 are not required or not appropriate.
It is important to note, that moisture sensitivity levels existing in both, J-STD-020F [1]and this
document, are equivalent.
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1 Scope
This part of IEC 61760 specifies the classification of moisture sensitive devicesmoisture
sensitive device (3.1) into moisture sensitivity levelsmoisture sensitivity level (3.2) related to
soldering heat, and provisions for packaging, labelling and handling.
This part of IEC 61760 extends the classification and packaging methods to such components,
where currently existing standards are not required or not appropriate. For such cases this
standard introduces additional moisture sensitivity levels and an alternative method for
packaging.
This standard applies to devices intended for reflow soldering, like surface mount devices,
including specific through-hole devices (where the device supplier has specifically documented
support for reflow soldering), but not to
• semiconductor devices,
• devices for flow (wave) soldering.
NOTE Background of this standard and its relation to currently existing standards, e.g. IEC 60749‑20 or J-STD-
020F [1]and J-STD-033 [2], are described in the INTRODUCTION.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60068‑1, Environmental testing – Part 1: General and guidance
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 61340‑5‑1, Electrostatics – Part 5-1: Protection of electronic devices from electrostatic
phenomena – General requirements
IEC 61760‑2, Surface mounting technology – Part 2: Transportation and storage conditions of
surface mounting devices (SMD) – Application guide
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
moisture sensitive device
MSD
device, where during soldering the evaporation of absorbed moisture is likely to deteriorate its
electrical or mechanical performance compared to what is given in the relevant specification
Note 1 to entry: This note applies to the French language only.
3.2
moisture sensitivity level
MSL
rating indicating a device’s susceptibility to damage due to absorbed moisture when subjected
to reflow soldering
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Note 1 to entry: This note applies to the French language only.
3.3
moisture barrier bag
MBB
bag designed to restrict the transmission of water vapour and used to pack moisture sensitive
devices
Note 1 to entry: This note applies to the French language only.
3.4
manufacturer’s exposure time
MET
maximum time after baking that the component manufacturer requires to process components
prior to sealing of the bag
Note 1 to entry: The manufacturer’s exposure time also includes the maximum time allowed at the distributor in
order to keep the bag open to split up its content into smaller shipments.
Note 2 to entry: This note applies to the French language only.
3.5
floor life
allowable time for a device or semi-finished assembly to be exposed to normal room
environment humidity and temperature after removal from a moisture barrier bag (3.3) or
storage chamber and before a solder reflow process
3.6
shelf life
recommendation of time that products can be stored in the original packaging, during which the
defined quality of the goods remains acceptable under specified conditions of transportation,
storage and handling
3.7
active desiccant
absorbent material used to maintain a low relative humidity
3.8
unit of desiccant
amount of active desiccant (3.7) that will absorb a minimum of 2,85 g of water vapour at 25 °C
and a relative humidity of 20 % within 24 h
3.9
moisture indicating desiccant
desiccant whose colour (hue) changes perceptibly, when a certain relative humidity is exceeded
Note 1 to entry: Typically a colour change due to a moisture indicating desiccant (3.9) is from blue to pink, when
the change from dry state to wet state is detected.
3.10
humidity indicator card
HIC
card on which a moisture sensitive chemical is printed such that it changes colour from dry to
wet when the indicated relative humidity is exceeded
Note 1 to entry: This note applies to the French language only.
3.11
water vapour transmission rate
WVTR
measure of the permeability of a plastic film material to moisture, used to specify a moisture
barrier bag (3.3) for dry packing

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Note 1 to entry: This note applies to the French language only.
4 General information
4.1 Moisture sensitive devices
Certain materials, plastic polymers and fillers are hygroscopic and can absorb moisture
dependent on time and the storage environment. Absorbed moisture will vaporize during rapid
heating in the solder reflow process, generating
• pressure in the material,
• deformation,
• swelling,
• delamination,
• cracking,
• degradation of inner connection.
The penetration of moisture into the absorbing material is generally caused through exposure
to the ambient air. Moisture absorption or moisture penetrating into cavities can lead to moisture
concentrations in the device which are high enough to cause cracking and/or delamination to
the device during the soldering process (e.g. “popcorn phenomenon”), which may adversely
affect reliability.
NOTE “Popcorn phenomenon”: internal stress causes the package to bulge and then crack with an audible “pop”.
Moisture can also influence the bonding strength of adhesives, sealings, encapsulants, plastics
with galvanic coating, etc.
Moisture exposure also can induce the transport of ionic contaminations into the device, thereby
increasing the potential for circuit failure due to corrosion.
Hence it is necessary to dry moisture-sensitive devices, to seal them in a moisture barrier bag
(3.3) and only to remove them immediately prior to soldering onto the circuit board. The
permissible time from the opening of the moisture barrier bag until the final soldering process
that a device can remain unprotected in an environment with a level of humid ity approximating
to real-world conditions (e.g. 30 °C/60 % RH) is a measure of the sensitivity of the device to
ambient humidity. This amount of time is called floor life (3.5).
4.2 moisture sensitivity level (3.2) (MSL)
The moisture sensitivity level (MSL) is determined at the classification temperature, which is
set above practical soldering temperatures. The actual soldering temperature measured at the
top surface of the component therefore shall be less than the classification temperature.
Packaging, storage, floor life (3.5) and pre-treatment of moisture sensitive devices before being
subjected to reflow soldering processes are identified by the MSL (see Clause 5 and Table 1).
The method for classification of devices into MSL is described in Clause 6.
4.3 Relation to other environmental test methods (humidity tests)
In humidity tests, for example as in IEC 60068‑2‑78 [3], devices are tested as they are
(unmounted) or in mounted condition, e.g. soldered to a test board. These tests detect the
influence of adsorbed or absorbed moisture to the performance of the device, e.g. electrical
characteristics, corrosion effects, but cannot detect the influence of absorbed moisture to the
sensitivity against heat stresses of the soldering processes.

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The target of the test method described in this document is to test the resistance of devices
against the soldering heat in combination with the humidity load as preconditioning process.
Other effects of humidity, like deterioration of electrical characteristics or isolation properties,
are not covered by this document and shall be tested separately.
5 Assessment of moisture sensitivity
5.1 Identification of non moisture sensitive devices
Non moisture sensitive devices shall be identified by analysis of design and materials of devices
depending on whether they can absorb humidity, or humidity can penetrate into cavities. If the
materials apparently do not absorb humidity, the devices may be declared by the manufacturer
as non moisture sensitive.
Such non moisture sensitive devices shall be designated as level “N”. There are no
requirements for non moisture sensitive devices.
5.2 Classification
The procedure to classify moisture sensitive devices into MSL is described in Clause 6. The
devices are classified at the appropriate classification temperature selected from Table 3 and
Table 4.
The recommended procedure is to start testing at the lowest moisture sensitivity level, which
the evaluation package is reasonably expected to pass (based on knowledge of other similar
evaluation packages).
If supplier and user agree, components can be classified at temperatures other than those in
Table 4.
If the conditions in Table 1 and/or Table 2 are not suitable for a specific product, other conditions
can be applied according to the agreement between users and suppliers.
Table 1 – Moisture sensitivity levels
LEVEL floor Floor life condition shelf life (3.6) Protective packaging Desiccant Humidity
life (reference indicator
(3.5) condition)
time
1 a ≤30 °C/85 % RH 12 months or as No requirement

specified by the
2 1 year ≤30 °C/60 % RH b No Optional
supplier
MBB type 1 , <60 %
a c
RH in MBB no pre-
drying
C2a 4 ≤30 °C/60 % RH b Yes c
MBB type 1 , <30 % Yes
weeks
RH in MBB no pre-
drying
2a b
MBB type 2 , <10 %
RH in MBB pre-drying
C3 168 h ≤30 °C/60 % RH b Yes c
MBB type 1 , <30 % Yes
RH in MBB no pre-
drying
3 b
MBB type 2 , <10 %
RH in MBB pre-drying
4 72 h ≤30 °C/60 % RH b Yes c
MBB type 2 , <10 % Yes
RH in MBB pre-drying
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LEVEL floor Floor life condition shelf life (3.6) Protective packaging Desiccant Humidity
life (reference indicator
(3.5) condition)
time
5 48 h ≤30 °C/60 % RH c Yes c
MBB type 2 ,  <10 % Yes
RH in MBB pre-drying
The floor life (3.5) can be longer if the environmental conditions are less severe than the
reference condition, or shorter, if more severe.
Extended shelf life (3.6) can be agreed upon, but needs recalculation of the amount of
desiccant.
a
The sum of keeping time at floor and storage time should not exceed the maximum storage period as specified
by the supplier.
b
The required shelf life (3.6) and humidity in packed condition shall be assured by the amount of the desiccant,
calculated by the use of WVTR (water vapour transmission rate) of the applied MBB. For the description of
MBB type, see Table 5.
c
Humidity indicator can be HIC or moisture indicating desiccant (3.9).
6 Test procedure
6.1 General
6.1.1 Structurally similar components
Classification may be performed for a group of structurally similar components. Information
about structural similarity shall be given in the relevant specification.
6.1.2 Verification and validation tests
The relevant specification shall describe the minimum number of specimens to be tested. The
minimum number should be at least 11 pieces.
NOTE A sample of 11 pieces tested with an acceptance number zero represents a Lot Tolerance Percent Defective
(LTPD) of 20 % with a confidence level (C.L.) of 90 %. See ISO 2859‑1 [4]for further information.
6.1.3 Selection of applicable soak conditions and temperature profile
The soak conditions related to the MSL shall be selected from Table 2, the applicable
temperature profile for classification (Figure 1) from Table 3 and Table 4.
6.2 Drying
Unless otherwise specified in the relevant specification, the specimen shall be baked at
125 °C ± 5 °C for at least 24 h.
However, alternative baking conditions can be applied, when confirmed by the mass gain or
loss analysis as described in Annex B.
6.3 Moisture soak
Table 2 – Moisture soak conditions
LEVEL Soak time h a Alternative
Soak condition
1 (168 +5/−0) (85 ± 2) °C, (85 ± 5) % RH (336 +5/−0) h; (85 ± 2) °C,
(60 ± 5) % RH
2 (168 +5/−0) (85 ± 2) °C, (60 ± 5) % RH –

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LEVEL Soak time h a Alternative
Soak condition
C2a (168 +5/−0)followed (85 ± 2) °C, (30 ± 5) % RH, followed –
by(672 +5/−0) by(30 ± 2) °C, (60 ± 5) % RH
2a (696 + 5/−0) (30 ± 2) °C, (60 ± 5) % RH
C3 (168 +5/−0)followed (85 ± 2) °C, (30 ± 5) % RH, followed
by(168 +5/−0) by(30 ± 2) °C, (60 ± 5) % RH
3 (192 +5/−0) (30 ± 2) °C, (60 ± 5) % RH
4 (96 +2/−0) (30 ± 2) °C, (60 ± 5) % RH
5 (72 +2/−0)
In levels C2a and C3, the first stage of soak condition corresponds to shelf life (3.6) (≤30 °C,
≤30 % RH, one year) in the MBB type 1. The second stage of soak condition corresponds to
floor life (3.5) (see IEC 60749‑20).
a
Soak conditions according to J-STD-020F [1]. Alternatively accelerated equivalent soak conditions from
Table 4 in J-STD-020F [1]may be applied in case the activation energy is confirmed by the manufacturer.
6.4 Temperature load
6.4.1 Classification temperature profile

Key
T Minimum preheating temperature
T Maximum preheating temperature
T Liquidus temperature
T Classification temperature
c
t Preheating duration
t Time at liquidus
t Time within (T – 5 °C)
3 c
t Time to T
4 c
a The temperature gradient of the increasing slope shall not exceed 3 K/s.
b Preheat area.
c The temperature gradient of the decreasing slope shall not exceed 6 K/s.
Figure 1 – Classification temperature profile
Table 3 – Parameters of the classification temperature profile
Solder process Sn-Pb (or equivalent) SnAgCu (or equivalent) Sn-Bi (or equivalent) [LTS]
T 100 °C 150 °C 100 °C
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Solder process Sn-Pb (or equivalent) SnAgCu (or equivalent) Sn-Bi (or equivalent) [LTS]
T 150 °C 200 °C 120 °C
t (60 to 120) s (60 to 120) s (30 to 90) s
T 183 °C 217 °C 139 °C
t (60 to 150) s (60 to 150) s (60 to 150) s
t 20 s 30 s 20 s
T See Table 4
c
t ≤6 min ≤8 min ≤4 min
Table 4 – Classification temperatures T
c
Solder process Package thickness Classification temperature T for package volume
c
3 3 3
<350 mm 350 mm to >2 000 mm
2 000 mm
mm °C °C °C
SnPb (or equivalent) <2,5 235 220 220
≥2,5 220 220 220
SnAgCu (or <1,6 260 260 260
equivalent)
1,6 to 2,5 260 250 245
>2,5 250 245 245
>2,5 plus high thermal capacity not b b
230 230
a applicable
Sn-Bi (or equivalent) All package thickness and volume: 190
[LTS]
a
This condition may be applied for devices with high thermal mass, where peak package temperature does not
reach 245 °C when soldered with a profile typical to soldering processes using SnAgCu alloy solder, or for
very temperature sensitive devices. The peak package temperature is measured at the device surface or any
other point specified in the relevant specification.
b
T measured at the device terminal or solder joint shall achieve the minimum temperature and time needed for
c
a specific solder alloy to form a solder joint.
6.4.2 Classification temperature profile for special devices
When the classification temperature profiles of Table 3and Table 4are not applicable to a device
(e.g. components with high thermal mass and/or thermal sensitivity) the temperature profiles in
IEC 60068-2-58:2015 [5], Table 7 can be used. Other profiles may be specified in the relevant
specification according to the agreement between user and supplier. For information see also
J-STD 075A [6].
6.4.3 Reflow
The sample shall be subjected to 3 cycles of the appropriate reflow conditions as defined in
Figure 1, Table 3and Table 4, starting in a time interval of 15 min to 4 h after removal from the
temperature/humidity chamber. The recovery period between two successive cycles shall be
the time it takes until the temperature of the specimen drops below 50 °C.
If the timing between removal from the temperature/humidity chamber and initial reflow cannot
be met, the parts shall be rebaked and resoaked according to 6.2 and 6.3.
All temperatures refer to the centre of the package, measured on the package body surface
that is facing up during assembly reflow (for example live-bug orientation).

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For users Tc shall not exceed the classification temperature in Table 4. For suppliers Tc shall
be equal to or exceed the classification temperature in Table 4.
NOTE 1 The temperature profile defined in Figure 1, Table 3and Table 4is comparable to the test conditions and
severities specified in IEC 60068-2-58:2015 [5], Environmental testing – Part 2-58: Tests – Test Td: Test methods
for solderability, resistance to dissolution of metallization and to soldering heat of surface mounting devices (SMD).
Thus, the temperature load used for testing resistance to soldering heat per each individual reflow treatment and for
moisture sensitivity is equivalent.
NOTE 2 The temperature profile defined in Figure 1, Table 3and Table 4conforms with Figure 1 and Table 5 of J-
STD-020F [1], which allow wider tolerances of, for example, peak temperature compared to the prescription given in
this document.
6.5 Recovery
The specimen shall be stored under the standard atmospheric conditions for measurements
and test as given in IEC 60068‑1, (15 to 35) °C, (25 to 75) % RH for the time given in the
relevant specification.
6.6 Final measurements
6.6.1 Requirements
A component is considered to pass that level of moisture sensitivity if it passes the requirements
of 6.6.2 and 6.6.3, and if required, the non-destructive inspection of 6.6.4.
6.6.2 Visual inspection
Visual inspection 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×.
A device shall be considered as failure if it exhibits any of the following:
a) external crack visible using 40× optical microscope;
b) internal crack or delamination that intersects internal connections;
c) internal crack or delamination extending from any terminal to any other internal element
relevant for the function of the device;
d) internal crack or delamination extending more than 2/3 the distance from any internal
element relevant for the function of the device to the outside of the package;
e) changes in package body flatness caused by warpage, swelling or bulging invisible to the
naked eye;
f) dimensions out of specification.
Hot temperature warpage may be specified for multi-pin devices. If parts meet in hot condition
co‑planarity and stand-off dimensions as specified at room temperature, they shall be
considered passing.
The relevant specification may prescribe additional inspection criteria.
If internal cracks are detected by non-destructive inspection in 6.6.4, they are considered a
failure or verified good using polished cross sections through the identified site.
For packages known to be sensitive to vertical cracks, it is recommended that polished cross
sections be used to confirm the non-existence of near vertical cracks within the mould
compound or encapsulant.
6.6.3 Electrical measurements
Electrical measurements on all devices shall be performed as required by the relevant
specification, e.g. datasheet, detail specifications, etc.

IEC CDV 61760-4 © IEC 2025 16 91/2039/CDV

6.6.4 Non-destructive inspection (if required)
If required by the relevant specification, non-destructive inspection (e.g. x-ray computed
tomography, scanning acoustic microscopy, etc.) shall be performed.
6.7 Classification
If one or more devices in the test sample fail at final measurements, the package shall be
considered not to have passed the tested level.
If a device does not pass level 5, it is classified as extremely moisture sensitive and dry pack
will not provide adequate protection. If such devices are shipped, the customer shall be advised
of its classification. The supplier shall also include a warning label with the devices indicating
that those either shall be socket mounted, or baked dry within a time given on the label before
reflow soldering.
6.8 Information to be given in the relevant specification
The following details shall be specified in the relevant specification:
a) MSL and classification temperature profile;
b) reject criteria, including non-destructive inspection criteria, in addition to those in 6.6.2
through 6.6.4;
c) any preconditioning requirements different to those given in 6.2 and 6.3.
7 Requirements to packaging and labelling
7.1 Packaging process
7.1.1 Drying of MSDs and carrier materials before being sealed in MBBs
7.1.1.1 Requirements – Levels 2, C2a and C3
Packing of the MSDs into MBBs shall be carried out under environmental conditions below
30 °C/60 % RH, within one week after moulding, burn-in, baking or other heating process.
MET is not specified.
MBBs may be opened for a short period of time, e.g less than 1 h, and re-closed provided, if
present, that the HIC indicates a humidity of less than 30 % RH and provided that the desiccant
is replaced with fresh desiccant. When the MBB is next opened, as long as the HIC indicates
below 30 % RH, the duration time of the previous MBB’s opening may be disregarded. Thus, if
the HIC indicates below 30 % RH when MBB is opened, the floor life (3.5) is not dependent on
the duration time of MBBs opening.
7.1.1.2 Drying requirements – Levels 2a, 3, 4 or 5
MSDs classified as levels 2a, 3, 4, or 5 shall be dried according to Clause 9 prior to being
sealed in MBBs. The period between drying and sealing shall not exceed the MET less the time
allowed for distributors to open the bags and repack parts. If the supplier’s actual MET is more
than the default 24 h, then the actual time shall be used. If the distributor practice is to repack
the MBBs with active desiccant (3.7), then this time does not need to be subtracted from the
MET.
Heating processes such as moulding, burn-in or baking can be regarded as pre-drying. If the
MSDs are stored in the low humidity controlled conditions until packaging into MBBs, MET can
be extended.
IEC CDV 61760-4 © IEC 2025 17 91/2039/CDV

7.1.1.3 Drying requirements – Carrier materials
The materials from which carriers such as trays, tubes, reels, etc. are made can affect the
desiccant capacity when placed in the MBB. Therefore, the effect of these materials shall be
compensated for by baking or, if required, adding additional desiccant in the MBB to ensure the
shelf life of the devices (see 8.1.2).
7.1.1.4 Drying requirements – Other
Suppliers may use the drying effect of normal in-line processes such as post mould cure,
marking cure, and burn-in to reduce the baking time. An equivalency evaluation is
recommended to ensure that high-temperature processing maintains moisture mass gain to an
acceptable level. The total mass gain for the device at the time it is sealed in the MBB shall not
exceed the moisture gain of that device starting dry and then being exposed to 30 °C and 60 %
RH for MET less the time for distributors.
7.1.1.5 Excess time between baking and packing
If the allowable time between baking and packing is exceeded, the devices shall be re-dried in
accordance with 9.1.
7.1.2 Evacuation and sealing
Type 1 packaging for MSL levels 2, C2a and C3 needs not to be evacuated.
For MBB only: The intimate packaging, e.g. reel, tray, tube may be evacuated and sealed to fix
intimate packaging, desiccant and HIC.
Partially or lightly evacuate to reduce the volume. The bag should not be completely evacuated
since this will reduce the effectiveness of the desiccant.
For better visual check it could be preferred to have a
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