IEC TR 61340-5-5:2018

IEC TR 61340-5-5 ®
Edition 1.0 2018-11
TECHNICAL
REPORT
colour
inside
Electrostatics –
Part 5-5: Protection of electronic devices from electrostatic phenomena –
Packaging systems used in electronic manufacturing
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IEC TR 61340-5-5 ®
Edition 1.0 2018-11
TECHNICAL
REPORT
colour
inside
Electrostatics –
Part 5-5: Protection of electronic devices from electrostatic phenomena –

Packaging systems used in electronic manufacturing

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 17.220.99; 29.020 ISBN 978-2-8322-6255-9

– 2 – IEC TR 61340-5-5:2018 © IEC 2018
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms . 9
4 Role of electrostatic protective packaging . 10
4.1 Analysis of electrostatic risks (what can cause problems to ESDS) . 10
4.2 Charge generation (separation) . 10
4.3 Reduction of electrostatic charging items in the environment . 13
4.4 Electrostatic attraction and repulsion issues . 13
4.5 Dissipation of electrostatic charge. 14
4.6 Barrier to ESD current . 14
4.7 Protection against electrostatic fields . 14
4.8 Chemical and outgassing issues . 14
4.9 Moisture barrier . 15
4.10 Environmental conditions affecting packaging materials . 15
4.11 Packaging material principles. 15
4.11.1 General . 15
4.11.2 Low charging . 15
4.11.3 Electrostatic charge dissipation . 15
4.11.4 Conductive materials . 16
4.11.5 Electrostatic field shielding . 16
4.11.6 Electrostatic discharge shielding . 16
5 Types of material . 16
5.1 Filled polymers . 16
5.2 Intrinsically conductive or dissipative . 17
5.3 Surface coated . 17
5.4 Antistat treated . 17
5.5 Anodized materials (e.g. boats used inside automated handlers, metal tubes)
............................................................................................................................. 17
5.6 Material processing . 17
5.6.1 Vacuum forming. 17
5.6.2 Injection moulding . 17
5.6.3 Embossing . 18
5.6.4 Vacuum vapour deposition . 18
5.6.5 Surface coating . 18
5.6.6 Lamination . 18
6 Existing standards for packaging materials . 18
6.1 IEC 61340-5-3 . 18
6.2 ANSI/ESD S541 . 18
6.3 Military standards and other documents related to packaging . 19
6.3.1 General . 19
6.3.2 MIL PRF 81705 (E) (Film) . 19
6.3.3 MIL STD 3010 . 19

6.3.4 MIL PRF 131 . 19
7 Existing test methods for packaging materials . 19
7.1 IEC 61340-2-1 – Ability of materials and products to dissipate static electric

charge . 19
7.2 IEC TR 61340-2-2 – Measurement of chargeability . 20
7.3 IEC 61340-2-3 – Resistance and resistivity . 20
7.4 IEC 61340-4-8 – Discharge shielding – Bags . 20
8 Choosing a packaging technology . 21
8.1 Determining packaging material attributes . 21
8.2 Inside an EPA . 21
8.3 Outside an EPA or between EPAs . 21
8.4 Evaluation of packaging system attributes . 21
8.5 Charge dissipation test methods . 21
8.6 Resistance measurement methods . 21
8.7 Shielding test . 22
9 Does the packaging system meet the intended purpose? . 22
10 New test method concepts and development plans . 22
10.1 General . 22
10.2 Single point probe . 23
10.3 Parallel plates . 23
10.4 Pin-point probe . 24
10.5 Shielding related test methods . 24
10.6 Charge generation – Triboelectrification test methods . 24
10.7 Triboelectric charging of cover tape . 26
10.8 Discharge evaluation method . 27
10.9 Other resistance test methods . 27
Annex A (informative) Packaging forms and types . 28
A.1 Packaging materials for electronic devices . 28
A.2 Embossed tape . 28
A.3 Cover tape . 28
A.4 Reel types and materials . 29
A.5 Injection moulded trays . 30
A.6 Tubes and rails and other configurations of packaging materials . 31
A.7 Clam shell and test socket . 32
A.8 Bags . 32
A.9 Tote boxes and other rigid containers . 33
Bibliography . 34

Figure 1 – Induction charging process – Grounding a conductor in the presence of an

electrical field . 11
Figure 2 – Second part of induction charging process . 12
Figure 3 – First discharge pulse that occurs as shown in Figure 1b . 12
Figure 4 – Second discharge pulse that occurs as shown in Figure 2 . 12
Figure 5 – Single point probe test method set–up . 23
Figure 6 – Single point probe on embossed (pocket) tape . 23
Figure 7 – Parallel plate test method set–up . 24
Figure 8 – Set–up of isolated tape reels . 25

– 4 – IEC TR 61340-5-5:2018 © IEC 2018
Figure 9 – Resistance measurements – Reel to reel . 25
Figure 10 – Charge drain test – Reel to reel. 26
Figure 11 – Cover tape evaluation concepts . 26
Figure 12 – Discharge evaluation method . 27
Figure A.1 – Examples of embossed (pocket) tape. 28
Figure A.2 – Cover tape . 29
Figure A.3 – Cover tape . 29
Figure A.4 – Cover tape . 29
Figure A.5 – Cover tape . 29
Figure A.6 – Cover tape . 29
Figure A.7 – Cover tape . 29
Figure A.8 – Cover tape . 29
Figure A.9 – Reels . 30
Figure A.10 – Reels . 30
Figure A.11 – Reels . 30
Figure A.12 – Reels . 30
Figure A.13 – Trays . 30
Figure A.14 – Trays . 30
Figure A.15 –Trays . 30
Figure A.16 – Trays . 31
Figure A.17– Trays . 31
Figure A.18 –Trays . 31
Figure A.19 – Trays . 31
Figure A.20 – Trays . 31
Figure A.21 – Trays . 31
Figure A.22 –Trays . 31
Figure A.23 – Trays . 31
Figure A.24 – Tubes . 32
Figure A.25 – Tubes . 32
Figure A.26 Tubes . 32
Figure A.27 –Clam shells . 32
Figure A.28 – Static discharge shielding bag . 33
Figure A.29 Moisture barrier – Metal foil bags . 33
Figure A.30 – Moisture barrier – Metal vapour deposition . 33
Figure A.31 – Box . 33
Figure A.32 – Rigid container . 33

Table 1 – Test methods for electrostatic protective packaging . 22

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROSTATICS –
Part 5-5: Protection of electronic devices from electrostatic phenomena –
Packaging systems used in electronic manufacturing

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a Technical Report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 61340-5-5, which is a Technical Report, has been prepared by IEC technical
committee 101: Electrostatics and IEC technical committee 40: Capacitors and resistors for
electronic equipment.
The text of this Technical Report is based on the following documents:
Draft TR Report on voting
101/564/DTR 101/575/RVDTR
Full information on the voting for the approval of this Technical Report can be found in the
report on voting indicated in the above table.

– 6 – IEC TR 61340-5-5:2018 © IEC 2018
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61340 series, published under the general title Electrostatics, 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.
A bilingual version of this publication may be issued at a later date.
IMPORTANT – 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
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INTRODUCTION
Packaging materials used within an electrostatic discharge (ESD) control programme often
are defined by an electrical resistance measurement. Packaging material manufacturers rely
on industry standardized test methods to ensure that the materials they supply meet industry
defined specifications. However, other attributes provided by a packaging material often are
difficult to quantify, leading to confusion between packaging material manufacturers and the
end users.
Increased use of automated handling equipment for the manufacture of electronic products
has resulted in changes in the design and form of packaging materials that contain electronic
parts and components. In particular, very small profile parts such as surface mount resistors
and capacitors are contained within pocket tape reels that are unloaded by automatic
equipment. Small dimension parts require small dimension packaging materials. Small
dimension packaging materials cannot be evaluated for electrical properties by the existing
industry accepted test methods.
Several types of packaging are used within the electronics industries that do not have the
basic properties generally associated with electrostatic control, such as paper tape. Industry
best practices involving these standard packaging material forms are discussed. Other forms
of packaging for non-ESDS (electrostatic discharge sensitive items) that are brought into the
ESD protected area (EPA) and considerations for handling such packaging forms are
described. This document has been prepared by a joint working group so that the
considerations of electrostatics and the application of protective measures are compatible
with the concerns of those who provide or use small dimension electronic components.

– 8 – IEC TR 61340-5-5:2018 © IEC 2018
ELECTROSTATICS –
Part 5-5: Protection of electronic devices from electrostatic phenomena –
Packaging systems used in electronic manufacturing

1 Scope
This part of IEC 61340 discusses packaging material requirements for electrostatic discharge
sensitive items (ESDS) as well as non–ESDS which can apply to packaging materials such as
embossed carrier tape, trays, tubes (stick magazines), rails and others used in back end line
processing and parts handling where test methods described in other standards are, for the
most part, inadequate. Issues related to electrostatic charge generation, electrostatic
attraction and repulsion are included. The recommendations and discussions within this
document can also be applicable to other types of packaging that cannot be evaluated by
other means.
This document discusses the issues related to
1) technical considerations for packaging material selection and packaging system design,
2) packaging material specifications for electrostatic control,
3) existing test methods and their limitations for packaging materials,
4) suggestions for the evaluation of small dimension packaging materials, and
5) industry common practices.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
electrostatic protective packaging
containers and other enclosures that have properties and functionality to limit electrostatic
charge generation, dissipate electrostatic charge, or limit interior electrostatic fields
3.1.2
intimate packaging
materials that come into direct contact with ESD sensitive items
3.1.3
proximity packaging
materials or items that cover or surround intimate packaging materials

3.1.4
conductive material
material with surface or volume conductive properties generally specified by electrical
resistance lower than dissipative materials
3.1.5
dissipative material
material with surface or volume conductive properties with an electrical resistance greater
than conductive materials but less than insulative materials
3.1.6
insulative material
material with electrical resistance high enough to impede charge flow to some degree
3.1.7
low charging
antistatic
property of a material that limits electrostatic charge transfer by contact and separation
(triboelectrification)
3.1.8
surface resistance
ratio of DC voltage to the current flowing between two electrodes of specified configuration
that contact the same side of a material
Note 1 to entry: Surface resistance is expressed in Ω.
3.1.9
surface resistivity
for electric current flowing across a surface, ratio of DC voltage drop per unit length to the
surface current per unit width
Note 1 to entry: In effect, the surface resistivity is the resistance between two electrodes on the opposite sides of
a square and is independent of the size of the square or its dimensional units.
Note 2 to entry: Surface resistivity is expressed in Ω. It is common practice to express surface resistivity in
ohms/square to distinguish from surface resistance.
3.1.10
volume resistance
ratio of the DC voltage per unit thickness to the amount of current per unit area passing
through a material
Note 1 to entry: Volume resistance is expressed in Ω.
3.1.11
electrostatic discharge shielding
materials that attenuate an electrostatic field and limit energy penetration induced by an
electrostatic discharge
3.1.12
electrostatic field shielding
materials that attenuate an electrostatic field
3.2 Abbreviated terms
CDM charged device model
CPM charged plate monitor
EPA ESD protected area
ESD electrostatic discharge
– 10 – IEC TR 61340-5-5:2018 © IEC 2018
ESDS electrostatic discharge sensitive item
HBM human body model
4 Role of electrostatic protective packaging
4.1 Analysis of electrostatic risks (what can cause problems to ESDS)
The risk to electronic parts, assemblies and equipment (collectively referred to as "ESDS")
from electrostatic phenomenon takes several forms and can be summarized as direct
electrostatic discharge from a charged conductor to the ESDS or electrostatic discharge from
the ESDS to another conductor (at a different potential) or ground if the ESDS becomes
excessively charged. Damage to an ESDS will always be the result of an excessive flow of
current through the ESDS.
It is necessary to note that the transfer of electrostatic charge (separation of charge) will
happen every time two materials come into contact and separate. The resulting separation of
charge will yield an equal positive and negative charge on the opposing surfaces. The
differences in interactions include how much charge is separated and where the charge goes
after it is separated, which is controlled by the electrical properties of the material. Charged
materials with the ability to conduct electricity can be neutralized (charge dissipation) by
contact with ground (earth). The rate of this charge neutralization/dissipation is controlled by
the electrical resistance of the material and the contact resistance between the material and
ground. The higher the resistance of the material and its contact resistance to ground, the
longer it will take to come to charge neutrality. A positively charged material will gain missing
electrons from ground while a negatively charged object will drain electrons to ground.
The amount of discharge an ESDS can tolerate is determined by a number of factors including
part sensitivity, assembly layout, rate of the charge transfer through the ESDS, total energy in
the discharge and environmental influences.
Discharge to an ESDS can occur by contact from a charged conductor, including a person,
machine component, tool or fixture or any other charged conductor involved in a process.
Reducing the probability of a damaging discharge to an ESDS is one of the principle methods
of electrostatic control. The risk of damage from charged conductors is reduced when all the
conductive materials and items are electrically bonded to ground. A grounded conductor
cannot hold an electrostatic charge.
Discharge from a charged ESDS to ground is controlled by reducing the charge accumulation
on the ESDS itself. Once an ESDS is charged, it is difficult to remove the charge without
some risk of excessive current flow through the ESDS. Therefore, one of the key factors in
packaging design is to reduce the charge generation propensity between an ESDS and the
container used for storage and shipment.
Charge generation cannot be reduced to "zero" but can be limited to below the threshold that
will cause excessive risk to the ESDS by the design of contacting surfaces, chemical changes
or additives placed in materials to alter surface charging characteristics and usually by
providing some level of electrical conductivity to allow charges to dissipate.
4.2 Charge generation (separation)
Triboelectric charging is the primary way that materials become charged. This process is
described by the actions of contact between dissimilar materials and then their separation.
The resulting charge level is influenced by the intimacy of contact, the speed of separation
and any rubbing motions that can be part of the contacting process before separation. The
physical properties of the surfaces of the contacting materials also influence the charging
process. Reducing the surface area of contact is one of the ways that triboelectric charging
can be reduced. Chemical additives to the material surfaces can also reduce charge
generation by decreasing the friction between the surfaces. Adding dissipative agents can

allow charges to spread out on surfaces or dissipate when in contact with ground thus
reducing the concentration of charge.
Charging by induction occurs when a conductive item is grounded while in the presence of an
electric field. While this is a complex phenomenon, it can occur where ESDS are handled in
both manual and automated processes if the electrical fields on materials in the environment
are not maintained below critical levels (determined by ESDS sensitivity). The first step in the
induction process occurs when an ESDS is brought into an electrical field. Charges realign
within the ESDS by polarization as shown in Figure 1 a). At this point, there is no charge
separation within the ESDS, only polarization.

a) Isolated conductor B polarized in the presence of electric field A

b) Conductor B grounded in the presence of electric field A – resulting in trapped charge on B.
Figure 1 – Induction charging process – Grounding a conductor
in the presence of an electrical field
If the ESDS is connected to ground while in the electric field, charge will flow to or from
ground depending on the polarity of the charge on the conductive portion of the ESDS. This is
the first discharge that occurs as shown in Figure 1 b).
If the ground connection is terminated before the electrical field removed from the area (this
happens when the part moves along in a process), a charge will be trapped on the ESDS as
shown in Figure 2 a). If another ground contact is made on the charged device, a second
discharge occurs that neutralizes the charge on the object, as shown in Figure 2 b).

– 12 – IEC TR 61340-5-5:2018 © IEC 2018

a) Charged device B after disconnecting from ground shown in Figure 1 b)

b) Discharge of charged device B by contact with ground
Figure 2 – Second part of induction charging process
Actual discharge pulses from an experimental induction process are shown in Figures 3 and 4.
As can be readily observed, there are nearly equal and opposite polarity discharge events in
each induction charging-discharging process.

Figure 3 – First discharge pulse that occurs as shown in Figure 1 b)

Figure 4 – Second discharge pulse that occurs as shown in Figure 2

If the structure of an ESDS is very small, the induction from an electric field may result in
internal voltage levels high enough to damage the ESDS. The critical voltage level depends
on the breakdown voltage of the insulating layers within the ESDS.
Charging by contact with a charged object can occur if the previously uncharged conductive
parts of an ESDS contact another conductor at a different potential. Charge sharing will occur
between conductors in this manner. The charge will discharge when the ESDS is connected to
ground, the same as the process shown in Figure 2 or by contact with an item with larger
capacitance and low resistance. There is a risk of damage if the current flow in the discharge
is over the ESDS sensitivity threshold.
4.3 Reduction of electrostatic charging items in the environment
The first step in reducing the risk of electrostatic damage in any process environment is to
make sure that all the electrically conductive or dissipative items and materials within that
environment are connected to ground or at least bonded together to share charge and
equalize electrical potential. ESDS can be handled with low risk from electrostatic discharge if
handled within the environment with equalized electrical potential.
The second step is to remove all unnecessary non-conductors (insulators) from the process
environment since the electrostatic charge on those materials cannot be dissipated by
grounding. If an insulative material is not needed in the process, it should be removed. The
electrical field strength where unprotected ESDS are handled shall not exceed 5 000 V/m.
Process essential insulators with surface electrostatic fields greater than 2 000 V at 2,5 cm
should be kept 30 cm away from the ESDS or the electrostatic field reduced to < 125 V at 2,5
cm for close proximity applications (< 2,5 cm). It has been shown experimentally that the size
of a charged insulator, the distance of separation from an ESDS, and the field strength all
should be considered in any risk assessment.
The third and most challenging step in reducing the process risk to ESDS is to reduce the
charge accumulation on the parts themselves. Since the contact and separation of the ESDS
from any surface can potentially cause charging, care should be taken in the evaluation and
selection of contacting materials, which includes packaging materials used for storage and
shipment.
The amount of charge that an ESDS can tolerate is the subject of much speculation and
discussion that is likely to continue for some time. The most logical assumption is that
charged device model (CDM) testing determines the sensitivity of a given ESDS to the
defined CDM discharge waveform and therefore an equivalent amount of charge measured on
the actual ESDS should be considered as a risk level for damage. Some relatively simple and
well understood charge measurements can be made on an ESDS, the capacitance of the
ESDS determined, and the voltage as well as stored energy calculated to compare to the
ESDS CDM failure threshold. While the direct relationship between the CDM and the actual
charge on an ESDS in a process might not be 1 to 1, the risks for damage can be better
understood in a process assessment so that the charging level threshold can be set.
Managing the charge generation on an ESDS can be monitored with a variety of instruments
including contact and non-contact electrostatic voltmeters and perhaps field meters if the
ESDS is large enough in area. It is likely that the most useful measurements will be made with
a Faraday cup or pail where the charge in coulombs is measured directly.
4.4 Electrostatic attraction and repulsion issues
One of the most important principles in electrostatics is that opposite sign charges attract and
same sign charges repel. The actual force that is present in attraction and repulsion is
determined by the charge on the involved items or materials and the resulting electric field.
The higher the charge, the stronger the electric field, and the stronger the attraction or
repulsion forces. This basic principle of attraction and repulsion is used throughout industry
and affects almost any activity that comes to mind. The copy machine in an office would not
work without this fundamental principle. Filters that clean the air in industrial processes would
lose efficiency without this principle. There are countless other activities that rely on this
simple law of physics that is learned in primary school around the world.

– 14 – IEC TR 61340-5-5:2018 © IEC 2018
This simple and well-known law of physics also is the cause of countless problems in industry
due to unwanted attraction or repulsion. Electrostatic charge and the resulting electric fields
cause dust attraction in a semiconductor wafer fabrication facility that can ruin electronic parts
while they are being imaged. Electrostatic attraction or repulsion can cause parts to not feed
correctly in automated handling equipment during circuit board assembly. Small profile parts
such as capacitors and resistors can be physically influenced by electric fields that would be
considered weak or inconsequential in many other applications.
The electric field requirements stated above in 4.3 might not be sufficient to reduce small part
clinging or attraction. Further reduction of electrostatic field strength can be necessary when
handling very small parts. Fortunately, the proper use of ionized air and the selection of low
charge generating packaging materials can help mitigate these small parts handling issues.
4.5 Dissipation of electrostatic charge
As mentioned in 4.1, electrostatic charge will dissipate or become neutralized by different
mechanisms, depending on the materials involved. Materials or items with some level of
conductivity will dissipate or lose their net charge by contact with ground. The rate of this
charge dissipation is controlled by the actual electrical resistance and capacitance involved in
the discharging circuit. For the purposes of packaging materials, the electrical resistance can
be relatively high on the surface of the material. Most of the standards call for a surface
resistance test method to measure packaging materials. The actual methods that are used
vary depending on the shape of the material and are discussed in Clause 6.
Electrostatic decay is one of the forms of charge dissipation that is used to determine the
upper limits of functionality for packaging materials. In concept, electrostatic decay is a
measurement of the time it takes for a sample under test to lose or equalize a defined portion
of charge when the sample is grounded. The electrostatic decay methods are discussed in
Clause 6.
4.6 Barrier to ESD current
Limiting or ideally preventing an electrostatic discharge from entering a packaging material
containing electrostatic discharge sensitive (ESDS) items is a function of an electrical
property known as insulation. Electrical insulation limits current or charge flow by definition
and the importance of insulation in electrical terms cannot be understated. Unfortunately,
insulating materials are also prone to gaining and holding electrostatic charge. One of the
primary packaging materials used in the protection of electronic items
...