Semiconductor devices - Part 5-4: Optoelectronic devices - Semiconductor lasers

IEC 60747-5-4:2022(E) specifies the terminology, the essential ratings and characteristics as well as the measuring methods of semiconductor lasers.
This edition includes the following significant technical changes with respect to the previous edition:  
References for the terms and definitions related to the lighting area, IEC 60050-845, are revised based on IEC 60050-845:2020;
Emission angle is changed to radiation angle in 3.3.2;
Definitions of rise time and fall time in 3.4.1 are revised based on the publication IEC 60050-521:2002;
Spectral linewidth is added to Table 1 in Clause 4;
Conditions for carrier-to-noise ratio of Table 1 in Clause 4 is amended.
Error in the equation for carrier-to-noise ratio in 5.2.2 is corrected;
Precaution against the equipment used for carrier-to-noise ratio measurement is added in 5.2.2;
Explanation for the measurement method of the small signal cut-off frequency in 5.3.2 of the first edition is deleted because it has been defined in the latest version of ISO 11554;
Reference document for the lifetime in 5.4 is amended;
Precaution against the measuring arrangement used for the half-intensity width and 1/e2-intensity is added in 5.5.3;
Reference tables in Annex A, Annex B and Annex C are revised by following the latest version of ISO publications.

General Information

Status
Published
Publication Date
26-Apr-2022
Current Stage
PPUB - Publication issued
Completion Date
27-Apr-2022
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IEC 60747-5-4
Edition 2.0 2022-04
INTERNATIONAL
STANDARD
Semiconductor devices –
Part 5-4: Optoelectronic devices – Semiconductor lasers
IEC 60747-5-4:2022-04(en)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60747-5-4
Edition 2.0 2022-04
INTERNATIONAL
STANDARD
Semiconductor devices –
Part 5-4: Optoelectronic devices – Semiconductor lasers
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.080.01; 31.260 ISBN 978-2-8322-1100-7

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

® Registered trademark of the International Electrotechnical Commission
---------------------- Page: 3 ----------------------
– 2 – IEC 60747-5-4:2022 © IEC 2022
CONTENTS

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

INTRODUCTION ..................................................................................................................... 6

1 Scope .............................................................................................................................. 7

2 Normative references ...................................................................................................... 7

3 Terms and definitions ...................................................................................................... 7

3.1 Physical concepts ................................................................................................... 8

3.2 Types of devices ..................................................................................................... 9

3.3 General terms ......................................................................................................... 9

3.4 Terms related to ratings and characteristics .......................................................... 10

3.4.1 Switching times ............................................................................................. 10

3.4.2 Output and current characteristics ................................................................. 12

3.5 Spatial profiles and spectral characteristics .......................................................... 15

4 Essential rating and characteristics ............................................................................... 15

4.1 Type ..................................................................................................................... 15

4.2 Semiconductor ...................................................................................................... 15

4.2.1 Material ......................................................................................................... 15

4.2.2 Structure ....................................................................................................... 15

4.3 Details of outline drawing and encapsulation......................................................... 16

4.4 Limiting values (absolute maximum ratings over the operating temperature

range, unless otherwise stated) ............................................................................ 16

4.5 Electrical and optical characteristics ..................................................................... 16

4.6 Supplementary information ................................................................................... 18

5 Measurement methods .................................................................................................. 18

5.1 Power measurement ............................................................................................. 18

5.2 Output stability ...................................................................................................... 18

5.2.1 Relative intensity noise .................................................................................. 18

5.2.2 Carrier-to-noise ratio ..................................................................................... 18

5.2.3 Output power stability .................................................................................... 20

5.2.4 Output energy stability ................................................................................... 20

5.2.5 Temporal pulse shape ................................................................................... 20

5.3 Time domain profile .............................................................................................. 20

5.3.1 Switching times ............................................................................................. 20

5.3.2 Small signal cut-off frequency (f ) .................................................................. 22

5.4 Lifetime ................................................................................................................. 22

5.5 Optical characteristics of the laser beam ............................................................... 23

5.5.1 Polarization ................................................................................................... 23

5.5.2 Half-intensity angle θ and 1/e -intensity angle θ 2 .................................... 23

1/2 1/e

5.5.3 Half-intensity width D and 1/e -intensity width D 2 ................................... 25

1/2 1/e

5.5.4 Spectral characteristics and other spatial profile ............................................ 26

Annex A (informative) Reference list of technical terms and definitions related to

spatial profile and spectral characteristics ............................................................................. 27

Annex B (informative) Reference list of measurement methods related to spatial

profile and spectral characteristics ........................................................................................ 31

Annex C (informative) Reference list of technical terms and definitions, and

measurement methods, related to power measurement and lifetime ...................................... 32

Bibliography .......................................................................................................................... 33

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IEC 60747-5-4:2022 © IEC 2022 – 3 –

Figure 1 – Example of the device with window but without lens ............................................. 10

Figure 2 – Switching times .................................................................................................... 12

Figure 3 – Threshold current of a laser diode ........................................................................ 14

Figure 4 – Basic circuit diagram ............................................................................................ 19

Figure 5 – Basic circuits diagram .......................................................................................... 21

Figure 6 – Typical pulse response diagram ........................................................................... 22

Figure 7 – Half-intensity angle .............................................................................................. 23

Figure 8 – Relationship between the specified plane and the mechanical reference

plane .................................................................................................................................... 23

Figure 9 – Basic measurement setup diagram ....................................................................... 24

Figure 10 – Measuring arrangement for D and D 2 ......................................................... 25

1/2 1/e

Table 1 – Electrical and optical characteristics ...................................................................... 17

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– 4 – IEC 60747-5-4:2022 © IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
Part 5-4: Optoelectronic devices –
Semiconductor lasers
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 this end and

in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,

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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with

may participate in this preparatory work. International, governmental and non-governmental organizations liaising

with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for

Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.

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

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

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Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

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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.

IEC 60747-5-4 has been prepared by subcommittee 47E: Discrete semiconductor devices, of

IEC technical committee 47: Semiconductor devices. It is an International Standard.

This second edition cancels and replaces the first edition published in 2006. This edition

constitutes a technical revision.

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

edition:

a) References for the terms and definitions related to the lighting area, IEC 60050-845, are

revised based on IEC 60050-845:2020;
b) Emission angle is changed to radiation angle in 3.3.2;

c) Definitions of rise time and fall time in 3.4.1 are revised based on the publication IEC 60050-

521:2002;
d) Spectral linewidth is added to Table 1 in Clause 4;
e) Conditions for carrier-to-noise ratio of Table 1 in Clause 4 is amended.
---------------------- Page: 6 ----------------------
IEC 60747-5-4:2022 © IEC 2022 – 5 –
f) Error in the equation for carrier-to-noise ratio in 5.2.2 is corrected;

g) Precaution against the equipment used for carrier-to-noise ratio measurement is added in

5.2.2;

h) Explanation for the measurement method of the small signal cut-off frequency in 5.3.2 of

the first edition is deleted because it has been defined in the latest version of ISO 11554;

i) Reference document for the lifetime in 5.4 is amended;

j) Precaution against the measuring arrangement used for the half-intensity width and 1/e -

intensity is added in 5.5.3;

k) Reference tables in Annex A, Annex B and Annex C are revised by following the latest

version of ISO publications.
The text of this International Standard is based on the following documents:
Draft Report on voting
47E/783/FDIS 47E/785/RVD

Full information on the voting for its approval can be found in the report on voting indicated in

the above table.
The language used for the development of this International Standard is English.

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available

at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are

described in greater detail at www.iec.ch/standardsdev/publications.

A list of all parts in the IEC 60747 series, published under the general title 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.
---------------------- Page: 7 ----------------------
– 6 – IEC 60747-5-4:2022 © IEC 2022
INTRODUCTION

The first edition of this part of IEC 60747 was published in 2006 under close collaboration

between IEC TC 47 SC 47E (IEC TC 47 SC 47C at that moment) and ISO TC 172 SC 9. The

scope of IEC/TC47/SC47E includes laser diodes as one of the discrete semiconductor devices

while that of ISO/TC172/SC9 includes laser diodes as one of the laser and laser-related

equipment. Consequently, technical contents in this publication extend over IEC and ISO.

In order to harmonize the IEC and ISO laser-related standards in 1997, a joint working group

(JWG) consisted of the experts from both IEC SC 47E and ISO TC 172 SC 9 was established.

As a result of discussion, items based on the electrical and electronic technologies are dealt

with by subcommittee 47E of IEC technical committee 47, while optical characteristics of the

output beam are under the responsibility of subcommittee 9 of ISO technical committee 172.

This was agreed, after long discussion, in 2002 between subcommittee 47E of IEC technical

committee 47 and subcommittee 9 of ISO technical committee 172. Based on this agreement,

terms and definitions, and test and measurement methods for the optical beam parameters in

this part of IEC 60747-5-4 are referenced to the ISO standards that specify the topics.

The joint working group was disbanded in 2017. However, close co-operation and contact

between two groups is indispensable in order to avoid any conflicts and to keep harmonization

of IEC and ISO laser standards.

This second edition of IEC 60747-5-4 has been updated by following the revision and

amendments in the latest versions of laser standards of both IEC and ISO.
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IEC 60747-5-4:2022 © IEC 2022 – 7 –
SEMICONDUCTOR DEVICES –
Part 5-4: Optoelectronic devices –
Semiconductor lasers
1 Scope

This part of IEC 60747 specifies the terminology, the essential ratings and characteristics as

well as the measuring methods of semiconductor lasers.
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 TR 62572-2, Fibre optic active components and devices – Reliability standards – Part 2:

Laser module degradation

ISO 11146-1, Lasers and laser-related equipment – Test methods for laser beam widths,

divergence angles and beam propagation ratios – Part 1: Stigmatic and simple astigmatic

beams

ISO 11554, Optics and photonics – Lasers and laser-related equipment – Test methods for laser

beam power, energy and temporal characteristics

ISO 12005, Lasers and laser-related equipment – Test methods for laser beam parameters –

Polarization

ISO 17526, Optics and optical instruments – Lasers and laser-related equipment – Lifetime of

lasers
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
---------------------- Page: 9 ----------------------
– 8 – IEC 60747-5-4:2022 © IEC 2022
3.1 Physical concepts
3.1.1
electromagnetic radiation,

phenomenon by which energy in the form of electromagnetic waves or photons emanates from

a source and is transferred through space

Note 1 to entry: The term “electromagnetic radiation” is also used for the electromagnetic waves or photons

produced (see IEV 705-02-01).

Note 2 to entry: The physical concepts of photons and electromagnetic waves are used to describe the same

phenomenon of transmission of radiant energy in different ways, depending on the nature of the interaction of the

energy with the physical world (wave-particle dualism).
[SOURCE: IEC 60050-702:1992/AMD5:2019, 702-02-07]
3.1.2
electromagnetic radiation,

energy that emanates from a source in the form of electromagnetic waves or photons and is

transferred through space

Note 1 to entry: The term “electromagnetic radiation” is also used for the phenomenon producing the

electromagnetic waves or photons (see IEV 702-02-07).

Note 2 to entry: The physical concepts of photons and electromagnetic waves are used to describe the same

phenomenon of transmission of radiant energy in different ways, depending on the nature of the interaction of the

energy with the physical world (wave-particle dualism).
[SOURCE: IEC 60050-705:1995/AMD4:2019, 705-02-01]
3.1.3
optical radiation

electromagnetic radiation at wavelengths between the region of transition to X-rays (λ ≈ 1 nm)

and the region of transition to radio waves (λ ≈ 1 mm)
Note 1 to entry: This entry was numbered 845-01-02 in IEC 60050-845:1987.
[SOURCE: IEC 60050-845:2020, 845-21-002]
3.1.4
light, noun

radiation that is considered from the point of view of its ability to excite the visual system

Note 1 to entry: The term "light" is sometimes used for optical radiation extending outside the visible range, but this

usage is not recommended.
Note 2 to entry: This entry was numbered 845-01-06 in IEC 60050-845:1987.
[SOURCE: IEC 60050-845:2020, 845-21-012]
3.1.5
light, noun
radiation within the spectral range of visible radiation

Note 1 to entry: Sometimes, the term "light" is also used in physics as a synonym of optical radiation, covering the

spectral range from 100 nm to 1 mm and sometimes even covering the X-ray spectral range. This misuse of the term

‘'light'' should be avoided.
[SOURCE: IEC 60050-845:2020, 845-21-013]
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IEC 60747-5-4:2022 © IEC 2022 – 9 –
3.1.6
visible radiation

optical radiation (IEV 845-21-002) capable of causing a visual sensation directly

Note 1 to entry: There are no precise limits for the spectral range of visible radiation since they depend upon the

amount of radiant flux reaching the retina and the responsivity of the observer. The lower limit is generally taken

between 360 nm and 400 nm and the upper limit between 760 nm and 830 nm.
Note 2 to entry: This entry was numbered 845-01-03 in IEC 60050-845:1987.

Note 3 to entry: ISO 20473:2007 Optics and photonics – Spectral bands defines from 380 nm to 780 nm for the

range of visible radiation.
[SOURCE: IEC 60050-845:2020, 845-021-003, modified – Note 3 has been added.]
3.2 Types of devices
3.2.1
semiconductor laser
laser diode

semiconductor diode that emits coherent optical radiation through stimulated emission resulting

from the recombination of conduction electrons and holes when excited by an electric current

that exceeds the threshold current of the diode

Note 1 to entry: The laser diode is mounted on a submount or in a package with or without coupling means

(e.g. lens, fibre pigtail).

[SOURCE: IEC 60050-521:2002, 521-04-37, modified – The term "laser diode" has been

replaced by "semiconductor laser".]
3.3 General terms
3.3.1
beam axis

straight line connecting the centroids defined by the first spatial moments of the cross-sectional

power (energy) density distribution function at successive locations in the direction of

propagation (z) of the beam in a homogeneous medium
[SOURCE: ISO 11145:2018, 3.2.1]
3.3.2
optical port

geometrical configuration, referenced to an external plane or surface of the device, that is used

to specify the optical radiation emitted from an emitting device
EXAMPLE
Signification of annotations in the Figure 1:
= acceptance angle or radiation angle
= optical port with diameter D
Ref. = reference locus for the definition of the optical port
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– 10 – IEC 60747-5-4:2022 © IEC 2022
Figure 1 – Example of the device with window but without lens

Note 1 to entry: The geometrical configuration should be specified by the manufacturer by means of geometrical

information, e.g:
– location, shape and size of the area of emission;
– angle of emission or acceptance;
– other parameters, e.g. numerical aperture of optical fibre;
– orientation of beam axis.
3.4 Terms related to ratings and characteristics
3.4.1 Switching times

Relation between the electrical input signal and the optical output signal is shown in Figure 2

with the indication of switching times.
3.4.1.1
rise time

time interval between the instants at which the magnitude of the pulse at the output terminals

reaches specified lower and upper limits respectively when the semiconductor device is being

switched from its non-conducting to its conducting state

Note 1 to entry: The lower and upper limits are usually 10 % and 90 % respectively of the final amplitude of the

output pulse.
[SOURCE: IEC 60050-521:2002, 521-05-22]
3.4.1.2
fall time

time interval between the instants at which the magnitude of the pulse at the output terminals

reaches specified upper and lower limits respectively when a semiconductor device is being

switched from its conducting to its non-conducting state

Note 1 to entry: The upper and lower limits are usually 90 % and 10 % respectively of the initial amplitude of the

output pulse.
[SOURCE: IEC 60050-521:2002, 521-05-24]
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IEC 60747-5-4:2022 © IEC 2022 – 11 –
3.4.1.3
turn-on delay time
d(on)

time interval between the instant the electrical input signal reaches a specified level (10 %

unless otherwise stated) and the instant the optical output signal reaches a specifies level

(10 % of the steady-state maximum unless otherwise stated)
3.4.1.4
turn-on time

time interval between the instant the electrical input signal reaches a specified level (10 %

unless otherwise stated) and the instant the optical output signal reaches a specified level (90 %

of the steady-state maximum unless otherwise stated)
t = t + t
on d(on) r
3.4.1.5
turn-off delay time
d(off)

time interval between the instant the electrical input signal downs a specified level (90 % unless

otherwise stated) and the instant the optical output signal downs a specifies level (90 % of the

steady-state maximum unless otherwise stated)
3.4.1.6
turn-off time
off

time interval between the instant the electrical input signal downs a specified level (90 % unless

otherwise stated) and the instant the optical output signal downs a specified level (10 % of the

steady-state maximum unless otherwise stated).
t = t + t
off d(off) f
---------------------- Page: 13 ----------------------
– 12 – IEC 60747-5-4:2022 © IEC 2022
Figure 2 – Switching times

NOTE Lower and upper specified values indicate 10 % and 90 %, respectively, unless otherwise stated.

3.4.2 Output and current characteristics
3.4.2.1
output power,
radiant power transferred from the semiconductor laser through the optical port

[SOURCE: ISO 11145:2018, 3.18, modified – The symbol “R(f)“has been replaced by “RIN”. ]

3.4.2.2
radiant flux
radiant power
change in radiant energy with time
Φ =
where Q is the radiant energy emitted, transferred or received, and t is time

Note 1 to entry: The corresponding photometric quantity is "luminous flux". The corresponding quantity for photons

is "photon flux".

Note 2 to entry: The term "radiant flux" is the preferred term for most radiometric applications, with the notable

exception of laser radiometry where the term "radiant power" is more commonly used.

Note 3 to entry: The radiant flux is expressed in watt (W).
---------------------- Page: 14 ----------------------
IEC 60747-5-4:2022 © IEC 2022 – 13 –
Note 4 to entry: This entry was numbered 845-01-24 in IEC 60050-845:1987.
[SOURCE: IEC 60050-845:2020, 845-21-038]
3.4.2.3
differential output power efficiency
output power efficiency for small-signal modulation:
η = dP/dI
d F
Note 1 to entry: Dimension of η is W/A.

Note 2 to entry: The term "small-signal modulation efficacy" is used as a synonym.

Note 3 to entry: Differential output power quantum efficiency = q/(hν). η is also applicable,

where
q is the electron charge,
ν is the optical frequency,
h is equal to 6,626 070 15 × 10-34 Js (Planck’s constant).
3.4.2.4
threshold current,
forward current derived from one of the following two methods:
a) derivative threshold current I
TH(D)

forward current at which the second derivative of the curve showing output power P versus

forward current I has its first maximum [see Figure 3 a)];
b) extrapolated threshold current

forward current at which the extrapolated two straight lines of the stimulated emission and the

spontaneous emission cross each other [see Figure 3 b)].
---------------------- Page: 15 ----------------------
– 14 – IEC 60747-5-4:2022 © IEC 2022
a) Derivative threshold current of a laser diode
b) Extrapolated threshold current of a laser diode
Figure 3 – Threshold current of a laser diode
3.4.3 Noise characteristics (of a semiconductor laser)
3.4.3.1
relative intensity noise
...

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