Semiconductor devices - Mechanical and climatic test methods - Part 18: Ionizing radiation (total dose)

IEC 60749-18:2019 is available as IEC 60749-18:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60749-18:2019 provides a test procedure for defining requirements for testing packaged semiconductor integrated circuits and discrete semiconductor devices for ionizing radiation (total dose) effects from a cobalt-60 (60Co) gamma ray source. Other suitable radiation sources can be used. This document addresses only steady-state irradiations, and is not applicable to pulse type irradiations. It is intended for military- and aerospace-related applications. It is a destructive test. This edition includes the following significant technical changes with respect to the previous edition:
- updates to subclauses to better align the test method with MIL-STD 883J, method 1019, including the use of enhanced low dose rate sensitivity (ELDRS) testing;
- addition of a Bibliography, which includes ASTM standards relevant to this test method.

Dispositifs à semiconducteurs - Méthodes d'essais mécaniques et climatiques - Partie 18: Rayonnements ionisants (dose totale)

IEC 60749-18:2019 est disponible sous forme de IEC 60749-18:2019 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.L’IEC 60749-18:2019 présente une procédure d’essai permettant de définir les exigences pour soumettre à essai des circuits intégrés à semiconducteurs sous boîtier et des dispositifs discrets à semiconducteurs, concernant les effets des rayonnements ionisants (dose totale) provenant d’une source de rayons gamma au cobalt-60 (60Co). D’autres sources de rayonnements appropriées peuvent être utilisées. Le présent document ne concerne que les irradiations continues et ne s’applique pas aux irradiations pulsées. Il est destiné aux applications des domaines militaire et aérospatial. Il s’agit d’un essai destructif. Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente:
- mises à jour apportées aux paragraphes afin de mieux aligner la méthode d’essai avec la méthode 1019 du document MIL-STD 883J, comprenant l’utilisation de l’essai de sensibilité accrue au faible débit de dose (ELDRS);
- ajout d’une bibliographie, comprenant les normes ASTM correspondant à la présente méthode d’essai.

General Information

Status
Published
Publication Date
09-Apr-2019
Technical Committee
Current Stage
PPUB - Publication issued
Completion Date
10-Apr-2019
Ref Project

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IEC 60749-18
Edition 2.0 2019-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Semiconductor devices – Mechanical and climatic test methods –
Part 18: Ionizing radiation (total dose)
Dispositifs à semiconducteurs – Méthodes d’essais mécaniques et climatiques –
Partie 18: Rayonnements ionisants (dose totale)
IEC 60749-18:2019-04(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60749-18
Edition 2.0 2019-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Semiconductor devices – Mechanical and climatic test methods –
Part 18: Ionizing radiation (total dose)
Dispositifs à semiconducteurs – Méthodes d’essais mécaniques et climatiques –
Partie 18: Rayonnements ionisants (dose totale)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.080.01 ISBN 978-2-8322-6755-4

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 60749-18:2019 © IEC 2019
CONTENTS

FOREWORD ........................................................................................................................... 4

1 Scope .............................................................................................................................. 6

2 Normative references ...................................................................................................... 6

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

4 Test apparatus ................................................................................................................ 8

4.1 Choice of apparatus ................................................................................................ 8

4.2 Radiation source ..................................................................................................... 8

4.3 Dosimetry system ................................................................................................... 8

4.4 Electrical test instruments ....................................................................................... 8

4.5 Test circuit board(s) ................................................................................................ 8

4.6 Cabling ................................................................................................................... 9

4.7 Interconnect or switching system ............................................................................ 9

4.8 Environmental chamber .......................................................................................... 9

4.9 Irradiation temperature chamber ............................................................................. 9

5 Procedure ........................................................................................................................ 9

5.1 Test plan ................................................................................................................. 9

5.2 Sample selection and handling ................................................................................ 9

5.3 Burn-in .................................................................................................................. 10

5.4 Dosimetry measurements ...................................................................................... 10

5.5 Lead/aluminium (Pb/Al) container ......................................................................... 10

5.6 Radiation level(s) .................................................................................................. 10

5.7 Radiation dose rate ............................................................................................... 10

5.7.1 Radiation dose rate determination ................................................................. 10

5.7.2 Condition A .................................................................................................... 11

5.7.3 Condition B .................................................................................................... 11

5.7.4 Condition C ................................................................................................... 11

5.7.5 Condition D ................................................................................................... 11

5.7.6 Condition E .................................................................................................... 11

5.8 Temperature requirements .................................................................................... 11

5.8.1 Room temperature radiation .......................................................................... 11

5.8.2 Elevated temperature irradiation .................................................................... 11

5.8.3 Cryogenic temperature irradiation .................................................................. 12

5.9 Electrical performance measurements .................................................................. 12

5.10 Test conditions ..................................................................................................... 12

5.10.1 Choice of test conditions................................................................................ 12

5.10.2 In-flux testing ................................................................................................. 12

5.10.3 Remote testing .............................................................................................. 12

5.10.4 Bias and loading conditions ........................................................................... 13

5.11 Post-irradiation procedure ..................................................................................... 13

5.12 Extended room temperature annealing test ........................................................... 14

5.12.1 Choice of annealing test ................................................................................ 14

5.12.2 Need to perform an extended room temperature annealing test ..................... 14

5.12.3 Extended room temperature annealing test procedure ................................... 14

5.13 MOS accelerated annealing test ........................................................................... 15

5.13.1 Choice of MOS accelerated annealing test .................................................... 15

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IEC 60749-18:2019 © IEC 2019 – 3 –

5.13.2 Need to perform accelerated annealing test ................................................... 15

5.13.3 Accelerated annealing test procedure ............................................................ 16

5.14 Test procedure for bipolar and BiCMOS linear or mixed signal devices with

intended application dose rates less than 0,5 Gy(Si)/s .......................................... 16

5.14.1 Need to perform ELDRS testing ..................................................................... 16

5.14.2 Determination of whether a part exhibits ELDRS............................................ 17

5.14.3 Characterization of ELDRS parts to determine the irradiation conditions

for production or lot acceptance testing ......................................................... 17

5.14.4 Low dose rate or elevated temperature irradiation test for bipolar or

BiCMOS linear or mixed-signal devices ......................................................... 18

5.15 Test report ............................................................................................................ 18

6 Summary ....................................................................................................................... 18

Bibliography .......................................................................................................................... 21

Figure 1 – Flow diagram for ionizing radiation test procedure for MOS and digital

bipolar devices...................................................................................................................... 19

Figure 2 – Flow diagram for ionizing radiation test procedure for bipolar (or BiCMOS)

linear or mixed-signal devices ............................................................................................... 20

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– 4 – IEC 60749-18:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –
Part 18: Ionizing radiation (total dose)
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

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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 60749-18 has been prepared by IEC technical committee 47:

Semiconductor devices.

This second edition cancels and replaces the first edition published in 2002. This edition

constitutes a technical revision.

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

edition:

a) updates to subclauses to better align the test method with MIL-STD 883J, method 1019,

including the use of enhanced low dose rate sensitivity (ELDRS) testing;

b) addition of a Bibliography, which includes ASTM standards relevant to this test method.

---------------------- Page: 6 ----------------------
IEC 60749-18:2019 © IEC 2019 – 5 –
The text of this International Standard is based on the following documents:
FDIS Report on voting
47/2539/FDIS 47/2554/RVD

Full information on the voting for the approval of this International Standard can be found in

the report on voting indicated in the above table.

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 60749 series, published under the general title Semiconductor

devices – Mechanical and climatic test methods, can be found on the IEC website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
---------------------- Page: 7 ----------------------
– 6 – IEC 60749-18:2019 © IEC 2019
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –
Part 18: Ionizing radiation (total dose)
1 Scope

This part of IEC 60749 provides a test procedure for defining requirements for testing

packaged semiconductor integrated circuits and discrete semiconductor devices for ionizing

radiation (total dose) effects from a cobalt-60 ( Co) gamma ray source. Other suitable

radiation sources can be used.
There are four tests presented in this procedure:
a) a standard room temperature irradiation test;
b) an irradiation at elevated temperature/cryogenic temperature test;
c) an accelerated annealing test;
d) an enhanced low dose rate sensitivity (ELDRS) test.

The accelerated annealing test estimates how dose rate ionizing radiation effects on devices

is important for low dose rate or certain other applications in which devices can exhibit

significant time-dependent effects. The ELDRS test determines if devices with bipolar linear

components exhibit sensitivity to enhanced radiation-induced damage at low dose rates.

This document addresses only steady-state irradiations, and is not applicable to pulse type

irradiations.
It is intended for military- and aerospace-related applications.

This document can produce severe degradation of the electrical properties of irradiated

devices and thus is considered a destructive test.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following

addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
ionizing radiation effects, pl

changes in the electrical parameters of a device or integrated circuit resulting from radiation-

induced charge
Note 1 to entry: These are also referred to as total dose effects.
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IEC 60749-18:2019 © IEC 2019 – 7 –
3.2
in-flux test
electrical measurements made on devices during irradiation exposure
3.3
internal dose pattern
logic condition of all elements within a logic circuit during radiation exposure
3.4
non in-flux test

electrical measurements made on devices at any time other than during irradiation

3.5
remote test

electrical measurements made on devices that are physically removed from the radiation

location
3.6
time-dependent effect
TDE

significant degradation in electrical parameters caused by the growth or annealing, or both, of

radiation-induced trapped charge after irradiation
Note 1 to entry: Similar effects also take place during irradiation.
Note 2 to entry: This note applies to the French language only.
3.7
accelerated annealing test
procedure utilizing elevated temperature to accelerate time-dependent effects
3.8
enhanced low dose rate sensitivity
ELDRS

part that shows enhanced radiation-induced damage at dose rates below 0,5 Gy(Si)/s

Note 1 to entry: This note applies to the French language only.
3.9
overtest

factor that is applied to the specification dose to determine the test dose level that the

samples have to pass to be acceptable at the specification level

Note 1 to entry: An overtest factor of 1,5 means that the parts should be tested at 1,5 times the specification dose.

3.10
parameter delta design margin
PDDM

design margin that is applied to the radiation-induced change in an electrical parameter

Note 1 to entry: For a PDDM of 2 the change in a parameter at a specified dose from the pre-irradiation value is

multiplied by two and added to the pre-irradiation value to see if the sample exceeds the post-irradiation parameter

limit. For example, if the pre-irradiation value of base current I is 30 nA and the post-irradiation value at 200 Gy(Si)

is 70 nA (change in I is 40 nA), then for a PDDM of 2 the post-irradiation value would be 110 nA

(30 nA + 2 x 40 nA). If the allowable post-irradiation limit is 100 nA, the part would fail.

---------------------- Page: 9 ----------------------
– 8 – IEC 60749-18:2019 © IEC 2019
4 Test apparatus
4.1 Choice of apparatus

The apparatus shall consist of the radiation source, electrical test instrumentation, test circuit

board(s), cabling, interconnect board or switching system, an appropriate dosimetry

measurement system, and an environmental chamber (if required for time-dependent effects

measurements). Adequate precautions shall be observed to obtain an electrical measurement

system with sufficient insulation, ample shielding, satisfactory grounding, and suitable low

noise characteristics.
4.2 Radiation source

The radiation source used in the test shall be the uniform field of a Co gamma ray source.

Uniformity of the radiation field in the volume where devices are irradiated shall be within ±10 %

as measured by the dosimetry system, unless otherwise specified. The intensity of the gamma

ray field of the Co source shall be known with an uncertainty of no more than ±5 %. Field

uniformity and intensity can be affected by changes in the location of the device with respect

to the radiation source and the presence of radiation absorption and scattering materials.

4.3 Dosimetry system

An appropriate dosimetry system shall be provided that is capable of carrying out the

measurements called for in 5.3 (see Bibliography).
4.4 Electrical test instruments

All instrumentation used for electrical measurements shall have the stability, accuracy, and

resolution required for accurate measurement of the electrical parameters. Any

instrumentation required to operate in a radiation environment shall be appropriately shielded.

4.5 Test circuit board(s)

Devices to be irradiated shall either be mounted on or connected to circuit boards together

with any associated circuitry necessary for device biasing during irradiation or for in situ

measurements. Unless otherwise specified, all device input terminals and any others

which can affect the radiation response shall be electrically connected during irradiation,

i.e. not left floating.

The geometry and materials of the completed board shall allow uniform irradiation of the

devices under test. Good design and construction practices shall be used to prevent

oscillations, minimize leakage currents, prevent electrical damage and obtain accurate

measurements. Only sockets that are radiation resistant and do not exhibit significant

leakages (relative to the devices under test) shall be used to mount devices and associated

circuitry to the test board(s).

All apparatus used repeatedly in radiation fields shall be checked periodically for physical or

electrical degradation. Components which are placed on the test circuit board, other than

devices under test, shall be insensitive to the accumulated radiation or they shall be shielded

from the radiation. Test fixtures shall be made such that materials will not perturb the

uniformity of the radiation field intensity on the devices under test.

Leakage current shall be measured outside the field of radiation. With no devices installed in

the sockets, the test circuit board shall be connected to the test system such that all expected

sources of noise and interference are operative. With the maximum specified bias for the test

device applied, the leakage current between any two terminals shall not exceed 10 % of the

lowest current limit value in the pre-irradiation device specification.
---------------------- Page: 10 ----------------------
IEC 60749-18:2019 © IEC 2019 – 9 –

Test circuit boards used to bias devices during accelerated annealing shall be capable of

withstanding the temperature requirements of the accelerated annealing test and shall be

checked before and after testing for physical and electrical degradation.
4.6 Cabling

Cables connecting the test circuit boards in the radiation field to the test instrumentation shall

be as short as possible. If long cables are necessary, line drivers can be required. The cables

shall have low capacitance and low leakage to ground, and low leakage between wires.

4.7 Interconnect or switching system

This system shall be located outside the radiation environment location, and provides the

interface between the test instrumentation and the devices under test. It is part of the entire

test system and subject to the limitation specified in 4.5 for leakage between terminals.

4.8 Environmental chamber

The environmental chamber for time-dependent effects testing, if required, shall be capable of

maintaining the selected accelerated annealing temperature within ±5 °C.
4.9 Irradiation temperature chamber

The irradiation temperature chamber, if required for elevated temperature irradiation should

be capable of maintaining a circuit under test at 100 °C ± 5 °C while it is being irradiated. The

chamber should be capable of raising the temperature of the circuit under test from room

temperature to the irradiation temperature within a reasonable time prior to irradiation and

cooling the circuit under test from the irradiation temperature to room temperature in less than

20 min following irradiation. The irradiation bias shall be maintained during the heating and

cooling. The method for raising, maintaining and lowering the temperature of the circuit under

test can be by conduction through a heat sink using heating and cooling fluids, by convection

using forced hot and cool air, or other means that will achieve the proper results. For

cryogenic temperature irradiations, the chamber should be capable of maintaining the test

device/unit at the required cryogenic temperature within ±5 °C (e.g., liquid helium or liquid

nitrogen) while it is being irradiated. The chamber should be capable of maintaining the

cryogenic temperature of the test device/unit during post-irradiation electrical testing.

5 Procedure
5.1 Test plan

The test devices shall be irradiated and subjected to accelerated annealing testing (if required

for time-dependent effects testing) as specified by a test plan. This plan shall specify the

device description, irradiation conditions, device bias conditions, dosimetry system, operating

conditions, measurement parameters and conditions and accelerated annealing test
conditions (if required).
5.2 Sample selection and handling

Only devices that have passed the electrical specifications as defined in the test plan shall be

submitted to radiation testing. Unless otherwise specified, the test samples shall be randomly

selected from the parent population and identically packaged. Each part shall be individually

identifiable to enable pre- and post-irradiation comparison. For device types that are

electrostatic discharge (ESD)-sensitive, proper handling techniques shall be used to prevent

damage to the devices.
---------------------- Page: 11 ----------------------
– 10 – IEC 60749-18:2019 © IEC 2019
5.3 Burn-in

For some devices, there are differences in the total dose radiation response before and after

burn-in. Unless it has been shown by prior characterization
...

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