IEC TR 62572-2:2008

IEC/TR 62572-2
Edition 1.0 2008-09
TECHNICAL
REPORT
Fibre optic active components and devices – Reliability standards –
Part 2: Laser module degradation

IEC/TR 62572-2:2008(E)
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IEC/TR 62572-2
Edition 1.0 2008-09
TECHNICAL
REPORT
Fibre optic active components and devices – Reliability standards –
Part 2: Laser module degradation

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
U
ICS 33.180; 31.260 ISBN 2-8318-9993-1
– 2 – TR 62572-2 © IEC:2008(E)
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references .7
3 Terms and definitions .7
4 Laser diode and laser module failure mechanisms.8
4.1 General .8
4.2 Description of the main failure mechanisms which affect laser diodes and
laser modules.9
4.2.1 Laser diodes.9
4.2.2 Monitor photodiode.13
4.2.3 TEC and thermistor .13
4.2.4 Packaging and optical fibre.14
5 Guidance on testing .14
5.1 Service life tests – General .14
5.2 Scale of testing .15
5.3 Screening of components (including burn-in) .15
5.3.1 Laser diodes.15
5.3.2 Monitor photodiode.16
5.3.3 Other components of the laser module .16
6 Guidance on the use of failure criteria during testing .16
7 Guidance on reliability predictions .19
7.1 Lifetime predictions .19
7.2 Failure rate prediction .21

Figure 1 – An example of cross-section for laser module .9
Figure 2 – Cross-section through a typical heterostructure laser (bonded section side up).10
Figure 3 – Schematic diagram of DSD and DLDs viewed from the direction
perpendicular to the (001) substrate .11
Figure 4 – Non-linearities in laser-current characteristics.18
Figure 5 – “Bathtub” failure rate curve.22
Figure 6 – Example of cumulative failure plot showing log-normal distribution of laser
failure rate. The sample number tested is 33. .23
Figure 7 – Calculate failure rates as a function of service term for components having
a log-normal lifetime distribution with a median life of 10 h and dispersion in the
range 0,5 to 2,0 .23

Table 1 – Example of laser diode screening and burn-in conditions .15
Table 2 – Example of monitor photodiode screening conditions .16
Table 3 – Example of life test failure criteria .17
Table 4 – Example of additional failure criteria for laser module service life tests .19
Table 5 – Example of failure criteria for laser modules after temperature cycling testing
and high-temperature storage testing.19
Table 6 – Recommended values of activation energy for lifetime predictions (when an
experimentally determined value is not available, i.e. default values).

TR 62572-2 © IEC:2008(E) – 3 –
Table 7 – Coefficient for upper and lower level of median life in log-normal distribution,
(tmp/tmh)1/σ .26
Table 8 – Multiplying coefficient for upper and lower level of dispersion.27
Table 9 – Failure rate for an exponential lifetime distribution .28

– 4 – TR 62572-2 © IEC:2008(E)

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC ACTIVE COMPONENTS AND DEVICES –
RELIABILITY STANDARDS –
Part 2: Laser module degradation

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
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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2) 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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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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.
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 61751-2, which is a technical report, has been prepared by subcommittee 86C: Fibre
optic systems and active devices of IEC technical committee 86: Fibre optics, based on the
Standard IEC 61751 prepared by subcommittee 47C: Optoelectronic, display and imaging
devices, of IEC technical committee 47: Semiconductor devices.
The field of this technical report will henceforth be placed under the responsibility of IEC
technical committee 86: Fibre optics.

TR 62572-2 © IEC:2008(E) – 5 –
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
86C/833/DTR 86C/847/RVC
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.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of IEC 62752 series, under the general title Fibre optic active components
and devices – Reliability standards, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site 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.
A bilingual version of this publication may be issued at a later date.

– 6 – TR 62572-2 © IEC:2008(E)
INTRODUCTION
The laser modules covered by this technical report are purchased by a system supplier (SS)
to be inserted in equipments which in turn are supplied/sold to a system operator (SO), for
example, a telecommunications company (see definitions in Clause 3).
For the system operator to act as an informed buyer, knowledge of the potential risks posed
by the use of critical components is required.
Optoelectronic component technology is continuing to develop. Consequently, during product
development phases, many failure mechanisms in laser modules have been identified. These
failure mechanisms, if undetected, could result in very short laser lifetime in system use.

TR 62572-2 © IEC:2008(E) – 7 –
FIBRE OPTIC ACTIVE COMPONENTS AND DEVICES –
RELIABILITY STANDARDS –
Part 2: Laser module degradation

1 Scope
This technical report deals with reliability assessment of laser modules used for
telecommunication guidance on testing, use of failure criteria and reliability predictions is
provided.
This technical report provides guidance on:
– the testing that a system supplier should ensure is in a place prior to procurement of a
laser module from a laser module manufacturer;
– a range of activities expected of a system supplier to verify a laser module manu
...