ISO 18115-2:2021

Surface chemical analysis — Vocabulary — Part 2: Terms used in scanning-probe microscopy

This document defines terms for surface chemical analysis. ISO 18115-1 covers general terms and those used in spectroscopy while this document covers terms used in scanning probe microscopy.

Analyse chimique des surfaces — Vocabulaire — Partie 2: Termes utilisés en microscopie à sonde à balayage

General Information

• Status: Published
• Publication Date: 20-Dec-2021
• ICS: 01.040.71 - Chemical technology (Vocabularies)
• ICS: 71.040.40 - Chemical analysis
• Technical Committee: ISO/TC 201/SC 1 - Terminology
• Drafting Committee: ISO/TC 201/SC 1 - Terminology
• Current Stage: 6060 - International Standard published
• Start Date: 21-Dec-2021
• Due Date: 27-Nov-2022
• Completion Date: 21-Dec-2021

Relations

• Revises: ISO 18115-2:2013 - Surface chemical analysis — Vocabulary — Part 2: Terms used in scanning-probe microscopy
• Effective Date: 26-Nov-2021

Standards Content (Sample)

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 18115-2
ISO/TC 201/SC 1
Surface chemical analysis —
Secretariat: ANSI
Vocabulary —
Voting begins on:
2021-09-30
Part 2:
Voting terminates on:
Terms used in scanning-probe
2021-11-25
microscopy
Analyse chimique des surfaces — Vocabulaire —
Partie 2: Termes utilisés en microscopie à sonde à balayage
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 18115-2:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2021
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ISO/FDIS 18115-2:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

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ISO/FDIS 18115-2:2021(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions ................................................................................................................................................................................... 1

3.1 Terms related to scanning probe microscopy methods .................................................................................... 1

4 Terms for contact mechanics models ............................................................................................................................................8

5 Terms for scanning probe methods ..............................................................................................................................................10

6 Terms related to supplementary scanning probe microscopy methods ..............................................34

7 Terms related to supplementary terms for scanning probe methods ....................................................38

Annex A (informative) List of abbreviated terms ...............................................................................................................................42

Bibliography .............................................................................................................................................................................................................................45

Index .................................................................................................................................................................................................................................................46

iii
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ISO/FDIS 18115-2:2021(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 201, Surface chemical analysis,

Subcommittee SC 1, Terminology.

This third edition cancels and replaces the second edition (ISO 18115-2:2013), of which it constitutes a

minor revision.
The changes to the previous edition are as follows:

— the term "Kelvin-force microscopy" has been replaced with "Kelvin-probe force microscopy" and,

where it occurred, the term "scanning-probe microscopy" has been replaced with "scanning probe

microscopy".
A list of all parts in the ISO 18115 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
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ISO/FDIS 18115-2:2021(E)
Introduction

Surface chemical analysis is an important area which involves interactions between people with

different backgrounds and from different fields. Those conducting surface chemical analysis might be

materials scientists, chemists, or physicists and might have a background that is primarily experimental

or primarily theoretical. Those making use of the surface chemical data extend beyond this group into

other disciplines.

With the present techniques of surface chemical analysis, compositional information is obtained for

regions close to a surface (generally within 20 nm) and composition-versus-depth information is

obtained with surface analytical techniques as surface layers are removed. The terms covered in this

document relate to scanning probe microscopy. The surface analytical terms covered in ISO 18115-1

extend from the techniques of electron spectroscopy and mass spectrometry to optical spectrometry

and X-ray analysis. Concepts for these techniques derive from disciplines as widely ranging as nuclear

physics and radiation science to physical chemistry and optics.

The wide range of disciplines and the individualities of national usages have led to different meanings

being attributed to particular terms and, again, different terms being used to describe the same concept.

To avoid the consequent misunderstandings and to facilitate the exchange of information, it is essential

to clarify the concepts, to establish the correct terms for use, and to establish their definitions.

The terms are given in alphabetical order, classified under the following:
— Clause 3: Definitions of the scanning probe microscopy methods;
— Clause 4: Acronyms and terms for contact mechanics models;
— Clause 5: Definitions of terms for scanning probe methods;
— Clause 6: Definitions of supplementary scanning probe microscopy methods;
— Clause 7: Definitions of supplementary terms for scanning probe methods.

In the terms in Clause 3, note that the final “M” or final “S” in the acronyms, given as “microscopy” or

“spectroscopy”, may also mean “microscope” or “spectrometer”, respectively, depending on the context.

For the definition relating to the microscope or spectrometer, replace the words “a method” by the

words “an instrument” where that appears.

In contact mechanics, covered in Clause 4, the basic theories are often referenced by acronyms. To avoid

confusion, these acronyms are defined below. These models all assume that the materials in contact are

homogeneous and isotropic, and have a linear elastic constitutive behaviour. Various contact models

for inhomogeneous, anisotropic, nonlinear, viscoelastic, elastoplastic, and other materials have been

derived and can be found in the literature.

Many terms concerned with profilometry, or more correctly, surface texture measuring instruments,

may be found in ISO 3274 and ISO 4287. ISO 3274 specifies the properties of the instrument that

influence profile evaluation and provides basic considerations of the specification of contact (stylus)

instruments (profile meter and profile recorder) whereas ISO 4287 concerns some issues involving

surface texture.

Those interested in a more detailed understanding of profilometry or surface texture measuring

instruments should consult ISO 3274, ISO 4287, ISO 25178 and other referenced documents.

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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 18115-2:2021(E)
Surface chemical analysis — Vocabulary —
Part 2:
Terms used in scanning-probe microscopy
1 Scope

This document defines terms for surface chemical analysis. ISO 18115-1 covers general terms and those

used in spectroscopy while this document covers terms used in scanning probe microscopy.

2 Normative references
There are no normative references in this document.
3 Terms and definitions

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

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1 Terms related to scanning probe microscopy methods
3.1.1
apertureless Raman microscopy

method of microscopy involving the acquisition of Raman spectroscopic data utilizing

a near-field (5.88) optical source and based upon a metal tip (5.120) in close proximity to the sample

surface illuminated with suitably polarized light
3.1.2
atomic-force microscopy
AFM
DEPRECATED: scanning force microscopy
DEPRECATED: SFM

method for imaging surfaces by mechanically scanning their surface contours, in which the deflection

of a sharp tip (5.120) sensing the surface forces, mounted on a compliant cantilever (5.18), is monitored

Note 1 to entry: AFM can provide a quantitative height image (5.69) of both insulating and conducting surfaces.

Note 2 to entry: Some AFM instruments move the sample in the x-, y- and z-directions while keeping the tip

position constant and others move the tip while keeping the sample position constant.

Note 3 to entry: AFM can be conducted in vacuum, a liquid, a controlled atmosphere, or air. Atomic resolution

may be attainable with suitable samples, with sharp tips, and by using an appropriate imaging mode.

Note 4 to entry: Many types of force can be measured, such as the normal forces (5.91) or the lateral (5.77), friction

(5.62), or shear force. When the latter is measured, the technique is referred to as lateral (3.1.13), frictional

(3.1.11), or shear force microscopy (3.1.37). This generic term encompasses all of the types of force microscopy

listed in Annex A.

Note 5 to entry: AFMs can be used to measure surface normal forces at individual points in the pixel array used

for imaging.
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ISO/FDIS 18115-2:2021(E)

Note 6 to entry: For typical AFM tips with radii < 100 nm, the normal force should be less than about 0,1 μN,

depending on the sample material, or irreversible surface deformation and excessive tip wear occur.

3.1.3
chemical-force microscopy
CFM

LFM (3.1.13) or AFM (3.1.2) mode in which the deflection of a sharp probe tip (5.120), functionalized to

provide interaction forces with specific molecules, is monitored
Note 1 to entry: LFM is the most popularly used mode.
3.1.4
conductive-probe atomic-force microscopy
CPAFM
DEPRECATED: CAFM
DEPRECATED: C-AFM

AFM (3.1.2) mode in which a conductive probe (5.109) is used to measure both topography and

electric current between the tip (5.120) and the sample

Note 1 to entry: CPAFM is a secondary imaging mode derived from contact AFM that characterizes conductivity

variations across medium- to low-conducting and semiconducting materials. Typically, a DC bias is applied to the

tip, and the sample is held at ground potential. While the z feedback signal is used to generate a normal-contact

AFM topography image (5.69), the current passing between the tip and the sample is measured to generate the

conductive AFM image.
3.1.5
current-imaging tunnelling spectroscopy
CITS

method in which the STM tip is held at a constant height above the surface, while the bias

voltage, V, is scanned and the tunnelling current, I, is measured and mapped

Note 1 to entry: The constant height is usually maintained by gating the feedback loop so that it is only active for

some proportion of the time; during the remaining time, the feedback loop is switched off and the applied tip bias

is ramped and the current is measured.
Note 2 to entry: See I-V spectroscopy (5.74).
3.1.6
dynamic-mode AFM
dynamic-force microscopy
DFM

AFM (3.1.2) mode in which the relative positions of the probe tip (5.120) and sample vary in a

sinusoidal manner at each point in the image (5.69)

Note 1 to entry: The sinusoidal oscillation is usually in the form of a vibration in the z-direction and is often

driven at a frequency close to, and sometimes equal to, the cantilever resonance frequency.

Note 2 to entry: The signal measured can be the amplitude, the phase shift, or the resonance frequency shift of

the cantilever.
3.1.7
electrostatic-force microscopy
DEPRECATED: electric-force microscopy

AFM (3.1.2) mode in which a conductive probe (5.109) is used to map both topography and

electrostatic force between the tip (5.120) and the sample surface
3.1.8
electrochemical atomic-force microscopy
EC-AFM

AFM (3.1.2) mode in which a conductive probe (5.109) is used in an electrolyte solution to

measure both topography and electrochemical current
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ISO/FDIS 18115-2:2021(E)
3.1.9
electrochemical scanning tunnelling microscopy
EC-STM

STM (3.1.34) mode in which a coated tip (5.120) is used in an electrolyte solution to measure

both topography and electrochemical current
3.1.10
frequency modulation atomic-force microscopy
FM-AFM

dynamic-mode AFM (3.1.6) in which the shift in resonance frequency (5.134) of the probe assembly (5.20)

is monitored and is adjusted to a set point using a feedback circuit
3.1.11
frictional-force microscopy
FFM
SPM (3.1.30) mode in which the friction force (5.62) is monitored

Note 1 to entry: The friction force can be detected in a static or frequency-modulated mode. Information on the

tilt azimuthal variation of the frictional force needs the static mode.
3.1.12
Kelvin-probe force microscopy
KPFM
DEPRECATED: KFM

dynamic-mode AFM (3.1.6) using a conducting probe tip to measure spatial or temporal changes in the

relative electric potentials of the tip and the surface

Note 1 to entry: Changes in the relative potentials reflect changes in the surface work function.

3.1.13
lateral-force microscopy
LFM

SPM (3.1.30) mode in which surface contours are scanned with a probe assembly (5.20) while monitoring

the lateral forces exerted on the probe tip (5.120) by observation of the torsion of the cantilever (5.18)

arising as a result of those forces

Note 1 to entry: The lateral forces can be detected in a static or frequency-modulated mode. Information on the

tilt azimuth of surface molecules needs the static mode.
3.1.14
magnetic dynamic-force microscopy
MDFM
DEPRECATED: magnetic AC mode
DEPRECATED: MAC mode

AFM (3.1.2) mode in which the probe (5.109) is oscillated by using a magnetic force (5.80)

3.1.15
magnetic-force microscopy
MFM

AFM (3.1.2) mode employing a probe assembly (5.20) that monitors both atomic forces and magnetic

interactions between the probe tip (5.120) and a surface
3.1.16
magnetic-resonance force microscopy
MRFM

AFM (3.1.2) imaging mode in which magnetic signals are mechanically detected by using a

cantilever (5.18) at resonance and the force arising from nuclear or electronic spin in the sample is

sensitively measured
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ISO/FDIS 18115-2:2021(E)
3.1.17
near-field scanning optical microscopy
NSOM
scanning near-field optical microscopy
SNOM

method of imaging surfaces optically in transmission or reflection by mechanically scanning an optically

active probe (5.109) much smaller than the wavelength of light over the surface while monitoring the

transmitted or reflected light or an associated signal in the near-field (5.88) regime

Note 1 to entry: See scattering NSOM (3.1.36), scattering SNOM (3.1.36).

Note 2 to entry: Topography is important and the probe is scanned at constant height. Usually, the probe is

oscillated in the shear mode to detect and set the height.

Note 3 to entry: Where the extent of the optical probe is defined by an aperture (5.5), the aperture size is

typically in the range of 10 nm to 100 nm, and this largely defines the resolution. This form of instrument is often

called an aperture NSOM or aperture SNOM to distinguish it from a scattering NSOM (3.1.36) or scattering SNOM

(3.1.36) [previously called apertureless NSOM (3.1.36) or apertureless SNOM (3.1.36)], although, generally, the

adjective “aperture” is omitted. In the apertureless form, the extent of the optically active probe is defined by an

illuminated sharp metal or metal-coated tip (5.120) with a radius typically in the range of 10 nm to 100 nm, and

this largely defines the resolution.

Note 4 to entry: In addition to the optical image (5.69), NSOM can provide a quantitative image of the surface

contours similar to that available in AFM (3.1.2) and allied scanning probe techniques.

Note 5 to entry: This generic term encompasses all of the types of near-field microscopy listed in Clause 2.

3.1.18
non-contact atomic-force microscopy
NC-AFM

dynamic-mode AFM (3.1.6) in which the probe tip (5.120) is operated at such a distance from the surface

that it samples the weak, attractive van der Waals or other forces

Note 1 to entry: Forces in this mode are very low and are best for studying soft materials or avoiding cross-

contamination of the tip and the surface.
3.1.19
photothermal micro-spectroscopy
PTMS

SThM mode in which the probe (5.109) detects the photothermal response of a sample exposed to

infrared light to obtain an absorption spectrum

Note 1 to entry: The infrared light can be either from a tuneable monochromatic source or from a broadband

source set up as part of a Fourier transform infrared spectrometer. In the latter case, the photothermal

temperature fluctuations can be measured as a function of time to provide an interferogram which is Fourier-

transformed to give the spectrum of sub-micron-sized regions of the sample.
3.1.20
scanning capacitance microscopy
SCM

SPM (3.1.30) mode in which a conductive probe (5.109) is used to measure both topography and

capacitance between the tip (5.120) and sample
3.1.21
scanning chemical-potential microscopy
SCPM

SPM (3.1.30) mode in which spatial variations in the thermoelectric voltage signal, created by a constant

temperature gradient normal to the sample surface, are measured and related to spatial variations in

the chemical-potential gradient
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ISO/FDIS 18115-2:2021(E)
3.1.22
scanning electrochemical microscopy
SECM

SPM (3.1.30) mode in which imaging occurs in an electrolyte solution with an electrochemically active

tip (5.120)

Note 1 to entry: See electrochemical atomic-force microscopy, EC-AFM (3.1.8), electrochemical scanning probe

microscopy, EC-SPM (6.5), electrochemical scanning tunnelling microscopy, EC-STM (3.1.9).

Note 2 to entry: In most cases, the SECM tip is an ultramicroelectrode and the tip signal is a Faradaic current

from electrolysis of solution species.

Note 3 to entry: The potential difference between the tip and either the sample or a reference electrode is usually

monitored.

Note 4 to entry: The liquid is usually an ionic or polar liquid in which an electric double layer exists at the sample

surface.

Note 5 to entry: The surface may be scanned with the tip at a constant height in the instrument frame to measure

the convolution of topography and electrochemical activity, or if the sample is electrochemically homogeneous,

in a feedback mode so that the tip is at a constant distance from the sample surface and the topography of the

surface is recorded.
3.1.23
scanning Hall probe microscopy
SHPM

SPM (3.1.30) mode in which a Hall probe is used as the scanning sensor to measure and map the

magnetic field from a sample surface
3.1.24
scanning ion conductance microscopy
SICM

SPM (3.1.30) mode in which an electrolyte-filled micropipette or nanopipette is used as a local probe

(5.109) for insulating samples immersed in an electrolytic solution

Note 1 to entry: The distance dependence of the ion conductance provides the key to performing non-contact

surface profiling.
3.1.25
scanning magneto-resistance microscopy
SMRM

SPM (3.1.30) mode in which a magneto-resistive sensor probe (5.109) on a cantilever (5.18) is scanned in

the contact mode (5.35) over a magnetic sample surface to measure two-dimensional magnetic images

(5.69) by acquiring magneto-resistive voltage
3.1.26
scanning Maxwell stress microscopy
SMSM

SPM (3.1.30) mode in which a conductive probe (5.109) is used to measure both topography and surface

potential by utilizing the Maxwell stress
3.1.27
scanning near-field thermal microscopy
SNTM

SNOM method in which an infrared-sensing thermometer is used to detect the local emission collected

by an optical probe (5.109) to measure both the topography and thermal properties

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ISO/FDIS 18115-2:2021(E)
3.1.28
scanning near-field ultrasound holography
SNFUH

method for imaging surfaces and the subsurface regimes by mechanically scanning their surface

contours and detecting the results of the interference of a high-frequency acoustic wave [of the order

of MHz or higher and substantially greater than the resonance frequency (5.134) of the cantilever (5.18)]

applied to the bottom of the sample while another wave is applied to the cantilever at a slightly different

frequency
3.1.29
scanning non-linear dielectric microscopy
SNDM

SPM (3.1.30) mode in which a conductive probe (5.109) is used to measure both topography and

dielectric constant (capacitance)
3.1.30
scanning probe microscopy
SPM

method of imaging surfaces by mechanically scanning a probe (5.109) over the surface under study, in

which the concomitant response of a detector is measured

Note 1 to entry: This generic term encompasses AFM (3.1.2), CFM (3.1.3), CITS (3.1.5), FFM (3.1.11), LFM (3.1.13),

SFM, SNOM (3.1.17), STM (3.1.34), TSM, etc. listed in Annex A.

Note 2 to entry: The resolution varies from that of STM, where individual atoms can be resolved, to SThM (3.1.33),

in which the resolution is generally limited to around 1 μm.
3.1.31
scanning spreading-resistance microscopy
SSRM

SPM (3.1.30) mode in which a conductive tip (5.120) is used to measure both topography and spreading

resistance

Note 1 to entry: While full-diamond or diamond-coated probes (5.109) are almost always used for the SSRM of

Si samples, it is possible to perform SSRM with other conductive tips when (in cases such as the imaging of InP,

which is soft) the use of a diamond tip could damage the sample.
3.1.32
scanning surface potential microscopy
SSPM

SPM (3.1.30) mode in which a conductive probe (5.109) is used to measure both topography and surface

potential

Note 1 to entry: KPFM (3.1.12) is SSPM conducted using an AFM (3.1.2) as defined in 3.1.13. Where this is

appropriate, KPFM should be used to describe the method rather than the more generic term, SSPM.

3.1.33
scanning thermal microscopy
SThM

SPM (3.1.30) method in which a thermal sensor is integrated into the probe (5.109) to measure both

topography and thermal properties

Note 1 to entry: Examples of such thermal properties are temperature and thermal conductivity.

Note 2 to entry: This method is sometimes known as thermal-scanning microscopy or TSM. This expression and

acronym are deprecated.
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ISO/FDIS 18115-2:2021(E)
3.1.34
scanning tunnelling microscopy
STM

SPM (3.1.30) mode for imaging conductive surfaces by mechanically scanning a sharp, voltage-biased,

conducting probe tip (5.120) over their surface, in which the data of the tunnelling (5.169) current and

the tip-surface separation are used in generating the image (5.69)

Note 1 to entry: STM can be conducted in vacuum, a liquid, or air. Atomic resolution can be achieved with suitable

samples and sharp probes and can, with ideal samples, provide localized bonding information around surface

atoms.

Note 2 to entry: Images can be formed from the height data at a constant tunnelling current or the tunnelling

current at a constant height or other modes at defined relative potentials of the tip and sample.

Note 3 to entry: STM can be used to map the densities of states at surfaces or, in ideal cases, around individual

atoms. The surface images can differ significantly, depending on the tip bias (5.159), even for the same topography.

3.1.35
scanning tunnelling spectroscopy
STS

STM (3.1.34) mode in which the tunnelling (5.169) current, I, between the tip (5.120) and the sample is

measured as the voltage, V, between the tip and the sample is scanned
Note 1 to entry: See I-V spectroscopy (5.74).

Note 2 to entry: The differential conductance, dI/dV, reflects the electronic local density of states (LDOS). If the

sample is a superconductor, the energy gap around the Fermi level can be characterized.

3.1.36
scattering NSOM/SNOM
s-NSOM
s-SNOM
DEPRECATED: apertureless NSOM
DEPRECATED: ANSOM
DEPRECATED: apertureless SNOM
DEPRECATED: ASNOM

method in which imaging at a resolution below the Abbe diffraction limit (5.1) is achieved by detecting

light scattered or emitted in the vicinity of a sharp scanning tip (5.120)

Note 1 to entry: ASNOM and ANSOM are both commonly used, and sometimes also mean apertured NSOM/SNOM

and apertureless NSOM/SNOM. To reduce the potential confusion, scattering NSOM/SNOM is recommended,

which is more descriptive of the technique than the earlier terms which describe what is not used.

Note 2 to entry: No aperture (5.5) defines the resolution of the instrument. Instead, the probed volume is defined

by scattering within the near-field region around the tip or the localized optical field distribution around the tip.

Note 3 to entry: The sharp tip is usually metallic or metal coated, permitting measurements of surface-enhanced

Raman (5.152) and fluorescence (5.52) spectroscopy and second harmonic generation (5.140). Raman signals of

molecules in close proximity to silver can be enhanced by a factor of 10 .

Note 4 to entry: The tip can be a single fluorescent molecule or nanoparticle (5.87).

Note 5 to entry: In the literature, the acronym ANSOM or ASNOM is occasionally used erroneously for aperture

NSOM or aperture SNOM.
3.1.37
shear force microscopy
ShFM

AFM (3.1.2) mode using signals arising from a probe tip (5.120) oscillating laterally in proximity

to the surface

Note 1 to entry: The oscillation is usually sinusoidal and generated through a piezoelectric actuator.

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ISO/FDIS 18115-2:2021(E)
3.1.38
spin-polarized scanning tunnelling microscopy
SP-STM
DEPRECATED: spin-resolved tunnelling microscopy
DEPRECATED: SRTM

STM (3.1.34) mode in which a magnetically ordered (ferromagnetic or antiferromagnetic) STM

tip (5.120) is scanned over a sample surface to image two-dimensional magnetic structures on the

nanometre scale by measuring the
...