IEC 62435-6:2018

IEC 62435-6 ®
Edition 1.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electronic components – Long-term storage of electronic semiconductor
devices –
Part 6: Packaged or finished devices

Composants électroniques – Stockage de longue durée des dispositifs
électroniques à semiconducteurs –
Partie 6: Dispositifs encapsulés ou finis

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IEC 62435-6 ®
Edition 1.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electronic components – Long-term storage of electronic semiconductor

devices –
Part 6: Packaged or finished devices

Composants électroniques – Stockage de longue durée des dispositifs

électroniques à semiconducteurs –

Partie 6: Dispositifs encapsulés ou finis

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.020 ISBN 978-2-8322-5979-5

– 2 – IEC 62435-6:2018 © IEC 2018
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Storage considerations . 9
4.1 Failure mechanisms . 9
4.1.1 Occurrence of failure and driving force . 9
4.1.2 Storage environment and mitigation for stimuli to prevent failure . 10
4.2 Materials management . 11
4.3 Storage media . 11
4.4 Inventory check. 11
4.5 Inventory dry packing refreshing . 12
4.6 Inventory re-assessment . 12
5 Baseline long-term storage requirements . 12
5.1 General . 12
5.1.1 Categories . 12
5.1.2 Critical aspects . 12
5.1.3 Recommendations and best practice . 12
5.2 Non-moisture sensitive device storage . 13
5.2.1 Storage media . 13
5.2.2 Lot data and labelling . 13
5.3 Moisture sensitive finished device storage . 13
5.3.1 Moisture sensitivity designation . 13
5.3.2 Dry packing for storage . 13
5.3.3 Moisture barrier bag . 13
5.3.4 Dunnage . 13
5.3.5 Humidity indicator card – HIC . 14
5.3.6 Desiccant . 14
5.3.7 Labelling . 14
5.4 Storage environment . 14
5.5 Process (temperature) sensitivity designation . 14
Annex A (informative) Packaged or finished device storage environment
considerations . 15
Bibliography . 16

Table 1 – Example failure mechanisms in storage and stimuli to mitigate during storage . 9
Table 2 – Long-term environment – Sustained condition requirements . 10
Table 3 – Considerations for management, control and documentation during storage . 11
Table A.1 – Long-term storage environment – Sustained condition considerations . 15

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRONIC COMPONENTS – LONG-TERM STORAGE OF
ELECTRONIC SEMICONDUCTOR DEVICES –

Part 6: Packaged or finished devices

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 interna-
tional co-operation on all questions concerning standardization in the electrical and electronic fields. To this
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62435-6 has been prepared by IEC technical committee 47: Semi-
conductor devices.
The text of this International Standard is based on the following documents:
FDIS Report on voting
47/2482/FDIS 47/2495/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.

– 4 – IEC 62435-6:2018 © IEC 2018
A list of all parts in the IEC 62435 series, published under the general title Electronic compo-
nents – Long-term storage of electronic semiconductor devices, 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.
INTRODUCTION
This document applies to the long-term storage of electronic components.
This is a standard for long-term storage (LTS) of electronic devices drawing on the best long-
term storage practices currently known. For the purposes of this standard, LTS is defined as
any device storage whose duration can be more than 12 months for product scheduled for
long duration storage. While intended to address the storage of unpackaged semiconductors
and packaged electronic devices, nothing in this document precludes the storage of other
items under the storage levels defined herein.
Although it has always existed to some extent, obsolescence of electronic components and
particularly of integrated circuits, has become increasingly intense over the last few years.
Indeed, with the existing technological boom, the commercial life of a component has become
very short compared with the life of industrial equipment such as that encountered in the aer-
onautical field, the railway industry or the energy sector.
The many solutions enabling obsolescence to be resolved are now identified. However, se-
lecting one of these solutions should be preceded by a case-by-case technical and economic
feasibility study, depending on whether storage is envisaged for field service or production,
for example:
• remedial storage as soon as components are no longer marketed;
• preventive storage anticipating declaration of obsolescence.
Taking into account the expected life of some installations, sometimes covering several dec-
ades, the qualification times, and the unavailability costs, which can also be very high, the
solution to be adopted to resolve obsolescence should often be rapidly implemented. This is
why the solution retained in most cases consists in systematically storing components which
are in the process of becoming obsolescent.
The technical risks of this solution are, a priori, fairly low. However, it requires perfect mastery
of the implemented process and especially of the storage environment, although this mastery
becomes critical when it comes to long-term storage.
All handling, protection, storage and test operations are recommended to be performed ac-
cording to the state of the art.
The application of the approach proposed in this document in no way guarantees that the
stored components are in perfect operating condition at the end of this storage. It only com-
prises a means of minimizing potential and probable degradation factors.
Some electronic device users have the need to store electronic devices for long periods of
time. Lifetime buys are commonly made to support production runs of assemblies that well
exceed the production timeframe of its individual parts. This puts the user in a situation re-
quiring careful and adequate storage of such parts to maintain the as-received solderability
and minimize any degradation effects to the part over time. Major degradation concerns are
moisture, electrostatic fields, ultraviolet light, large variations in temperature, air-borne con-
taminants, and outgassing.
Warranties and sparing also present a challenge for the user or repair agency as some sys-
tems have been designated to be used for long periods of time, in some cases for up to
40 years or more. Some of the devices needed for repair of these systems will not be availa-
ble from the original component manufacturer for the lifetime of the system or the spare as-
sembly can be built with the original production run but then requires long-term storage. This
document was developed to provide a standard for storing electronic devices for long periods

– 6 – IEC 62435-6:2018 © IEC 2018
of time. For storage of devices that are moisture sensitive but that do not need to be stored
for long periods of time, IEC TR 62258-3 can be consulted.
Long-term storage assumes that the device is going to be placed in uninterrupted storage for
a number of years. It is essential that it is useable after storage. Particular attention should be
paid to storage media surrounding the devices together with the local environment.
These guidelines do not imply any warranty of product or guarantee of operation beyond the
storage time given by the original component manufacturer.
The IEC 62435 series is intended to ensure that adequate reliability is achieved for devices in
user applications after long-term storage. Users are encouraged to request data from suppli-
ers to applicable specifications to demonstrate a successful storage life as requested by the
user. These standards are not intended to address built-in failure mechanisms that would take
place regardless of storage conditions.
These standards are intended to give practical guide to methods of long-duration storage of
electronic components where this is intentional or planned storage of product for a number of
years. Storage regimes for work-in-progress production are managed according to company
internal process requirements and are not detailed in this series of standards.
The overall standard is split into a number of parts. Parts 1 to 4 apply to any long-term stor-
age and contain general requirements and guidance, whereas Parts 5 to 9 specific to the type
of product being stored. It is intended that the product specific part should be read alongside
the general requirements of Parts 1 to 4.
Electronic components requiring different storage conditions are planned to be covered sepa-
rately starting with Part 5.
The structure of the IEC 62435 series as currently conceived is as follows:
– Part 1 – General
– Part 2 – Deterioration mechanisms
– Part 3 – Data
– Part 4 – Storage
– Part 5 – Die and wafer devices
– Part 6 – Packaged or finished devices
– Part 7 – MEMS
– Part 8 – Passive electronic devices
– Part 9 – Special cases
ELECTRONIC COMPONENTS – LONG-TERM STORAGE OF
ELECTRONIC SEMICONDUCTOR DEVICES –

Part 6: Packaged or finished devices

1 Scope
This part of IEC 62435 on long-term storage applies to packaged or finished devices in long-
term storage that can be used as part of obsolescence mitigation strategy. Long-term storage
refers to a duration that can be more than 12 months for product scheduled for storage. Phi-
losophy, good working practice, and general means to facilitate the successful long-term stor-
age of electronic components are also addressed.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their con-
tent 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: Re-
sistance of plastic encapsulated SMDs to the combined effect of moisture and soldering heat
IEC 60749-20-1, 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
JEDEC J-STD-020, Moisture/reflow classification for nonhermetic solid state surface mount
devices
JEDEC J-STD-075, Classification of non-IC electronic components for assembly processes
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 ad-
dresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
storage environment
specially controlled storage area, with particular control of temperature, humidity, atmosphere
and any other conditions depending on the product requirements
3.2
critical moisture limit
maximum safe equilibrium moisture content for a specific encapsulated device at reflow as-
sembly or rework
– 8 – IEC 62435-6:2018 © IEC 2018
3.3
long-term storage
LTS
planned storage of components to extend the life-cycle for a duration with the intention of
supporting future use
Note 1 to entry: Allowable storage durations will vary by form factor (for example; packing materials, shape) and
storage conditions. In general, long-term storage is longer than 12 months.
3.4
LTS storeroom
area containing components that have additional packaging for storage to protect from mois-
ture or from mechanical impact or for ease of identification or handling
3.5
moisture-sensitive device
MSD
device that has moisture absorption or moisture retention and whose quality or reliability is
affected by moisture
3.6
electronic device
packaged electrical, electronic, electro-mechanical (EEE) item, or assemblies using such
items
3.7
desiccant
hygroscopic substance used to remove moisture from an atmosphere
3.8
moisture barrier bag
MBB
storage bag manufactured with a flexible laminated vapour barrier film that restricts the
transmission of water vapour
Note 1 to entry: Refer to IEC 60749-20-1 for packaging of moisture sensitive products.
3.9
humidity indicator card
HIC
card printed with a moisture sensitive chemical that changes, typically, from blue to pink in
the presence of water vapour
3.10
water vapour transmission rate
WVTR
measure of permeability of MBBs to water vapour
3.11
dunnage
all the matter stored in a moisture barrier bag that is additional to the packaged electronic
component
3.12
electrostatic discharge
ESD
transfer of electric charge between bodies of different electrostatic potentials in proximity or
through direct contact
[SOURCE: IEC 60050-561:2014, 561-03-06]
4 Storage considerations
4.1 Failure mechanisms
4.1.1 Occurrence of failure and driving force
Failures during long-term storage may be mitigated by control of the stimuli and driving forces
likely to initiate given failure modes of interest as defined by a Failure Modes and Effects
Analysis (FMEA). Storage related failures are often detected as modes of non-operation, vis-
ual quality or other non-conformance. The modes of failure during storage are typically related
to a failure mechanism that is driven by a physical stimuli or condition. Successful long-term
storage is accomplished by controlling the failure mechanism stimuli as identified using a fail-
ure modes and effect analysis based on information from technology development and test-
ing. Table 1 provides examples of failure stimuli. Additional examples of deterioration mecha-
nisms are found in IEC 62435-2. Successful long-term storage is accomplished by mitigating
failures through control of the stimuli or driving force.
Table 1 – Example failure mechanisms in storage and stimuli to mitigate during storage
Failure Failure mechanism detail Failure mode Mechanism stimuli
mechanism
Popcorn High rate vapour expansion Open circuit, blistering, Temperature increase leading to
effect within a package during sur- package cracks moisture vapour
face mounting
Handling Cracking Open, short, visible crack Application of force
damage
Visible scratch/smudge Open, short, surface mark Mechanical abrasion
Device data Electro-magnetic current Open, short, data corrup- Electro-magnetic field
loss/damage field induced tion
short/open/error
High ionizing radiation in- Open, short, data corrup- High-energy radiation, x-ray
duced open, short or error tion
Soft error resulting from Open, short or data cor- Neutron particle hit
device damage ruption
Alpha particle emission hit
Staining Change in surface appear- Visible defect, non- Exposure resulting in aging, oxida-
residue ance and specification re- conforming appearance tion or hardening of residue
sulting from unplanned ex- and potential of mispro-
posure to oxidizing contents cessing
Polymer Polymer embrittlement Visible cracking, open or Temperature exposure, residual
material shorting mechanical stress and bright light
aging
Storage Tape on reel, tube embrit- Misalignment during pro- Temperature exposure, mechanical
media tlement/aging cessing stressing and bright light
issues
Tray and tube aging embrit- Dropped parts from broken Temperature, handling and bright
tlement tray media or parts out of light
formed pocket
Dropped parts
Box aging embrittlement Temperature and bright light
Opens or shorts from ESD
Foreign material
ESD coating degradations Opens or shorts from ESD Triboelectric charging or charge
potential difference
Label aging Illegible mark Bright light, temperature
Missing label Temperature and bright light
Brittle flaking – partial Temperature and bright light
label
– 10 – IEC 62435-6:2018 © IEC 2018
Failure Failure mechanism detail Failure mode Mechanism stimuli
mechanism
Indirect Moisture barrier bag leak Humidity indicator card Handling abrasion, bending and
material trigger, visual non- shock events
issues conformance
Humidity Indicator Card In- Incorrect colour or no Temperature, humidity Exposure
activated moisture exposure indicat- before use
ed
Label aging Illegible mark Bright light, temperature
Missing label Temperature and bright light
Brittle flaking – partial Temperature and bright light
label
Solderability Inability to form a good sol- Post surface mount elec- Temperature, humidity Exposure
der joint trical open
Corrosion Electro-chemical reaction Open, short, visual non- Temperature, galvanic cell, chemi-
leading failure conformance cal residue
Tin Whisker filament formed by Visual whiskers, short Bright tin(Sn) surface finish (un-
dislocations in metal films alloyed) crystal dislocation growth
whiskers
with a gradient in surface (in un-mitigated parts)
mechanical stress.
Sulphur gas catalysed reaction
Wettability Passivation surface change Flux or adhesion change Surface energy change
4.1.2 Storage environment and mitigation for stimuli to prevent failure
Mitigation of failures during and after long-term storage occurs by directly controlling or limit-
ing the stimulus for failure by a number of means. Common requirements for sustained long-
term storage are given in Table 2. Knowledge and control of the storage environment is of
primary importance to identify the risk of failure occurrence and to control or eliminate failure
stimuli during storage. Examples of the storage environment are contained in IEC 62435-4.
Other storage environment parameters related to long-term storage that may be important for
products or devices with certain sensitivities are presented in Annex A. It is the responsibility
of the end customer to maintain the storage environment as well as to ensure that terms and
conditions are in place for successful long-term storage at the time of product purchase and
at storage from a storage service provided, if used.
The full component thermal and environmental chain should be considered in planning the
reliability characterization evaluation, for estimation of the reliability after storage which is
added to the use reliability estimates.
If components storage is entrusted to a storage service provider, the customer shall define
the storage environment conditions according to the components sensitivity (see Table 2 and
Table A.1) unless the service provider has the competence to do this.
Table 2 – Long-term environment – Sustained condition requirements
Storage Range (terrestrial storage) Failure Mitigation
Environment
a, b
Temperature Temperature controls or
low/high: + 5 °C / + 40 °C
geographical placement
Relative Humidity Dry pack
low/high: 10 %/85 % RH
(RH) non-condensing
c
a
IEC 60721-3-1 storage classification 1K21
b
ASHRAE – climate control class A3 and class C for temperature
c
RH greater control > 7% is required for ESD control.

Other storage environments of interest are: chemical activity, pressure, altitude and magnetic
fields. Other considerations are provided in Table A.1.
4.2 Materials management
Long-term materials storage management includes storage of identification data either in
physical form and/or in electronic form as determined by the organization responsible for the
storage, supplier, distributor, and with customer agreement. The objective of data retention
schemes is to identify discrepant material either due to spoilage, mishandling, and originally
undetected attributes and to maintain chain of custody evidence to prevent counterfeit.
Table 3 – Considerations for management, control and documentation during storage
Storage information Storage data Form or method
category
Data/aging Lot date code Box/bag date label, barcode/matrix code, physical
mark.
Dry packing date
Environment deviations Alarms Box/bag date label and lot history, barcode/matrix
code, physical mark or database history
Qualifications Original qualification report Supplier/distributor report, report database
Inventory check report (if agreed)
Inventory requalification report
Extended storage justification

4.3 Storage media
The storage media refers to trays, tubes, tape-and-reel, bulk bag or other purpose built pack-
aging for storage of finished products. A good solution for storage is to utilize the packaging
originally used by the original component manufacture that is marked with its logo or name.
Care should be taken to ensure the media does itself not contain absorbed or adsorbed mois-
ture, chemical contaminants or oils that may make their way to the units being stored. Media
should employ electrostatic mitigation. Media may include dunnage used to secure the trays
together during handling and include tension bands and/or straps that are subject to the same
requirements as trays, documentation/paper lot identifiers.
Lot information and documentation can be stored with units in LTS as a method to ensure unit
level and lot level identification during storage and prior to use. Lot information recorded on
paper and electronic devices are subject to the same restrictions for absorbed or adsorbed
moisture, chemical contaminants or oils that may provide stimuli for failure of parts upon final
assembly.
4.4 Inventory check
Inventory checking may be accomplished by either passive or active means depending upon
business needs and terms of the obligation. Passive inventory checks are advantageous to
ensure proper accounting and minimal added handling.
Active checking may involve inspection, retest, requalification or inventory accounting. Added
handling, in the case of active checking, introduces additional risk to parts by un-intended ex-
posure or damage. Examples of unintended damage include: damage to moisture barrier bags
resulting in a leak detected at a later time as well as electrostatic discharge which may be de-
tected at system integration at a later time. A special case of inventory check may be neces-
sary when a new test program is implemented or when a manufacturing issue is detected and
found to affect stored inventory. The organization responsible for storage should manage the
process and notify the customer of issues prior to shipment of stored units to the customer as
defined by business agreements. The supplier may determine to manage the process proac-
tively as an issue is uncovered or passively; prior to shipment to the customer. It is the re-

– 12 – IEC 62435-6:2018 © IEC 2018
sponsibility of the organization responsible for storage to manage the inventory to the perfor-
mance specification sheet and the terms and conditions of the business agreement.
Added handling during an active inventory check and re-assessment is a practice that should
be properly planned and executed to prevent handling damage, electrostatic discharge and
violation of ambient moisture exposures.
4.5 Inventory dry packing refreshing
A new dry packaging operation may be required after an active inventory check. Refreshing of
the desiccant and moisture humidity indicator card should be controlled within a small time
interval taking care to limit moisture or other exposures. A refresh may be necessary if the
desiccant used for storage is insufficient in quantity or if moisture has leaked into a rated
moisture barrier bag. Similarly, it may be required to refresh with a new humidity indicator
card when the storage duration is beyond the demonstrated life or capability of the card to
detect moisture exposure.
4.6 Inventory re-assessment
Inventory re-assessment testing should be performed as required. It is not recommended to
perform full inventory re-assessment testing but rather use sampling of inventory to determine
remaining life or continued suitability for use. The sampling plan shall, in this case, adhere to
the rules defined in the standards (for example ISO 2859-1).
5 Baseline long-term storage requirements
5.1 General
5.1.1 Categories
Long-term storage may be divided into two categories for non-moisture sensitive devices as
well as moisture sensitive devices. It is often the case that the moisture sensitive device stor-
age and precautions are also applicable to non-moisture sensitive storage to mitigate any
perceived risks.
5.1.2 Critical aspects
Storage of moisture sensitive components requires that all failure modes are mitigated and
that unit level traceability, supply chain of custody are in place and that critical aspects of the
storage environment are known and controlled. IEC 62435-2, IEC 62435-4, and JEDEC JEP-
160 describe failure mechanisms of interest and typical failure mitigation methods. It is good
practice to establish the storage time and environment as when the technology is developed
prior to certification or qualification so that added requirements can be integrated if required.
Storage requirements beyond the basic storage requirements in this document are the re-
sponsibility of the supplier, distributor or organization responsible of the storage as agreed to
in the terms and conditions of the purchasing contract.
5.1.3 Recommendations and best practice
Devices that are not moisture sensitive should be packed and stored to reduce exposure to
dust, condensed moisture, chemical outgassing products and pollution residue. Mechanical
integrity and resistance to electrostatic discharge should also be maintained. Dry packing may
be utilized to enhance storage time (5.3.2).

5.2 Non-moisture sensitive device storage
5.2.1 Storage media
Any storage media used for long-term storage should be made of antistatic material and be
free of surface contaminants or outgassing by-products that may act as stimuli for failure dur-
ing final assembly.
5.2.2 Lot data and labelling
Data that indicates the product and traceability information should be stored with the units,
physically or electronically. Consideration should also be given to the storage of lot data
stored in paper or electronic device form. Paired lot information should be tied to unit and lot
traceability data. Data storage is planned as IEC 62435-3 which may be utilized upon publi-
cation.
5.3 Moisture sensitive finished device storage
5.3.1 Moisture sensitivity designation
Moisture sensitive devices shall be tested and rated according to IEC 60749-20 and JEDEC J-
STD-020 prior to packing and storage. Packing shall be performed to ensure that the board or
system integration function is capable to utilize the declared floor life or recoverable floor life
after baking. Package labelling shall identify moisture sensitivity parts and the designated
moisture sensitivity rating per IEC 60749-20-1 and JEDEC J-STD-020.
5.3.2 Dry packing for storage
If the device is rated as moisture sensitive then dry packing with desiccant and a humidity in-
dicator card is required. The process for moisture barrier bag selection and determination of
desiccant quantity is outlined in IEC 60749-20-1 or JEDEC J-STD-033.
5.3.3 Moisture barrier bag
Moisture barrier bags used for long-term storage shall be rated for durability and the moisture
vapour transmission rate. The durability ensures a minimum level of handling capability. The
moisture vapour transmission rate, correlated to the leak rate is used to determine the quanti-
ty of desiccant needed to absorb the moisture leaked in to the bag over the duration of the
long-term storage.
5.3.4 Dunnage
Dunnage refers to all matter stored in a moisture barrier bag that is additional to the packaged
electronic component. Examples of dunnage include: JEDEC trays, tape and reel, securing
straps and paper.
It is important to know the details of the dunnage moisture absorption prior to packing as well
as the occurrence of outgassing from the dunnage. Moisture that is absorbed into dunnage is
required to be considered in the calculations for amount of required desiccant.
Outgassing from dunnage should be considered because residues may contribute to next-
level assembly integration issues or corrosion and oxidation of exposed metal which results in
long-term reliability reduction.
The minimum and maximum rating for environmental exposure shall be known to ensure that
ambient storage excursions do not impact the ability of the media to protect the component
during and after storage. Accommodation should be made to avoid storage media degradation
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Under preparation. Stage at the time of publication: IEC/CCDV 62435-3:2018.

– 14 – IEC 62435-6:2018 © IEC 2018
(cracking, flaking or peeling) for the duration of storage. If components are stored in tape then
the stored tape shall also be capable of being processed by the placement tool in a normal
manner. It should be noted that some cover tapes and their adhesion may be compromised in
storage resulting in dropping of units when storage parts are removed from the tape at final
assembly.
5.3.5 Humidity indicator card – HIC
Humidity indicator cards in most cases should be packed in moisture barrier bags that contain
moisture sensitive electronics components. The validity of the humidity indicator card should
be assessed periodically.
5.3.6 Desiccant
The appropriate quantity of desiccant should be added to the moisture barrier bag to ensure
the customer or end-user receives the maximum declared time out of bag as indicated by the
moisture sensitivity level rating. The standards that should be used for desiccant charging are
IEC 60721-20-1 and JEDEC J-STD-033. The standards show the mathematical relationships
for determination of the appropriate desiccant to be placed inside the moisture barrier bag
given a characteristic moisture vapour transmission rating, the maximum moisture uptake for
the dunnage and the moisture removal capability of the desiccant for the intended storage
duration.
5.3.7 Labelling
5.3.7.1 General
The lowest level of packing shall indicate the dry pack date and the lot traceability infor-
mation. The bag seal date indicates the beginning of the controlled storage period from which
the duration of storage can be determined. IEC 60721-20-1 and JEDEC J-STD-020 provide
requirements for labelling.
5.3.7.2 Lot data and labelling
The data that indicates the product and traceability information should be stored with the
units, physically or electronically. Consideration should also be given to the storage of lot data
stored in paper form or electronic device form. Paired lot information should be tied to unit
and lot traceability data. Data storage is planned as IEC 62435-3 which may be utilized upon
publication.
5.4 Storage environment
The ambient environment conditions of the intended storage area shall be assessed and de-
fined and should be controlled prior to electronic component storage. See Table 2 for envi-
ronment control requirements. The desiccant calculations and the technology or product quali-
fication plan may be adjusted to comprehend the storage environment. It is good practice to
consider events that may result in short duration exposures outside the normal, average con-
ditions to ensure that the storage media are capable of protecting the component parts.
5.5 Process (temperature)
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