ISO 11505:2025

International
Standard
ISO 11505
Second edition
Surface chemical analysis —
2025-06
General procedures for quantitative
compositional depth profiling by
glow discharge optical emission
spectrometry
Analyse chimique des surfaces — Modes opératoires généraux
pour le profilage en profondeur compositionnel quantitatif par
spectrométrie d'émission optique à décharge luminescente
Reference number
© ISO 2025
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ii
Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Apparatus . 2
5.1 Glow discharge optical emission spectrometer .2
5.1.1 General .2
5.1.2 Selection of spectral lines.2
5.1.3 Selection of glow discharge source type .2
6 Adjusting the glow discharge spectrometer system settings . 3
6.1 General .3
6.2 Setting the discharge parameters of a DC source .4
6.2.1 Constant applied current and voltage .4
6.2.2 Constant applied current and pressure .5
6.2.3 Constant applied voltage and pressure .5
6.3 Setting the discharge parameters of an RF source .6
6.3.1 Constant applied power and pressure .6
6.3.2 Constant applied power and DC bias voltage .6
6.3.3 Constant effective power and RF voltage.7
6.4 Minimum performance requirements .7
6.4.1 General .7
6.4.2 Control of lamp cleanliness and start-up performance .7
6.4.3 Minimum repeatabilitry .9
6.4.4 Detection limit .9
7 Sampling .11
8 Calibration .11
8.1 General .11
8.2 Calibration specimens.11
8.2.1 General .11
8.2.2 Low-alloy iron or steel specimens . 12
8.2.3 Stainless-steel specimens. 12
8.2.4 High-oxygen specimens . 12
8.2.5 High-carbon specimens . 12
8.2.6 High-nitrogen specimens . 12
8.2.7 High-purity copper specimens. 12
8.2.8 High-purity zinc specimens . 13
8.3 Validation specimens . 13
8.4 Determination of the sputtering rate of calibration and validation specimens. 13
8.5 Emission intensity measurements of calibration specimens .14
8.6 Calculation of calibration formulae .14
8.7 Validation of the calibration .14
8.7.1 General .14
8.7.2 Checking analytical accuracy using bulk reference materials . 15
8.7.3 Checking analytical accuracy using surface layer reference materials . 15
8.8 Verification and drift correction . 15
9 Analysis of test specimens . .16
9.1 Adjusting discharge parameters .16
9.2 Setting of measuring time and data acquisition rate .16
9.3 Quantifying depth profiles of test specimens .16
10 Expression of results . 16

iii
10.1 Expression of quantitative depth profile .16
10.2 Determination of total coating mass per unit area .17
10.3 Determination of average mass fractions .18
11 Precision .18
12 Test report .18
Annex A (normative) Calculation of calibration constants and quantitative evaluation of depth
profiles. 19
Annex B (informative) Suggested spectral lines for determination of given elements .32
Bibliography .34

iv
Foreword
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The procedures used to develop this document and those intended for its further maintenance are described
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of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
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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 8, Glow discharge spectroscopy.
This second edition cancels and replaces the first edition (ISO11505:2012), which has been technically
revised.
The main changes are as follows:
— the listed types of array detectors have been updated;
— advances in measurement techniques and apparatus have expanded the applicable sample sizes, and
modifications have been made to optimize the optics, vacuum and detection systems;
— the text “setting of the high voltage for the detectors” is replaced with “setting of the parameters for
detector sensitivity” throughout the documents;
— the instructions to optimize the crater shape has been changed from mandatory to optional.
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.

v
International Standard ISO 11505:2025(en)
Surface chemical analysis — General procedures for
quantitative compositional depth profiling by glow discharge
optical emission spectrometry
1 Scope
This document specifies a glow discharge optical emission spectrometric (GD-OES) method for the
determination of the thickness, mass per unit area and chemical composition of surface layer films.
The applicability of this document is limited to description of general procedures for quantification of
the chemical composition and thickness in GD-OES compositional depth profiling. This document is not
directly applicable for quantification of individual materials having various thicknesses and elements to be
determined.
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.
ISO 14707, Surface chemical analysis — Glow discharge optical emission spectrometry (GD-OES) —
Introduction to use
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology 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/
4 Principle
The analytical method described in this document involves the following processes:
a) cathodic sputtering of the surface layer in a direct current or radio frequency glow discharge device;
b) excitation of the analyte atoms and ions in the plasma formed in the glow discharge device;
c) spectrometric measurement of the intensities of characteristic spectral emission lines of the analyte
atoms and ions as a function of sputtering time (qualitative depth profile);
d) conversion of the qualitative depth profile in units of intensity versus time to mass fraction versus
depth by means of calibration functions (quantification). Calibration of the system is achieved by
measurements on calibration specimens of known chemical composition and measured sputtering rate.

5 Apparatus
5.1 Glow discharge optical emission spectrometer
5.1.1 General
The required instrumentation includes an optical emission spectrometer system consisting of a Grimm
[6]
type or similar glow discharge source (direct current or radio frequency powered) and a simultaneous
optical spectrometer which shall be in accordance with ISO 14707, capable of providing suitable spectral
lines for the analyte elements. Sequential optical spectrometers (monochromators) are not suitable, since
several analytical wavelengths must be measured simultaneously at high data acquisition speed. An array-
type detector, such as a charge coupled device (CCD), a complementary metal-oxide-semiconductor device
(CMOS) or a charge injection device (CID) can also be used for simultaneous detection to cover a wide
spectral range of the analytical lines.
The inner diameter of the hollow anode of the glow discharge source should be in the range 1 mm to 8 mm. A
cooling device for thin specimens, such as a metal block with circulating cooling liquid, is also recommended,
but not strictly necessary for implementation of the method.
Since the principle of determination is based on continuous sputtering of the surface layer, the spectrometer
shall be equipped with a digital readout system for time-resolved measurement of the emission intensities.
A system capable of a data acquisition speed of at least 100 measurements/second per spectral channel is
recommended, but, for a large number of applications, speeds of > 50 measurements/second per spectral
channel are acceptable.
NOTE Pulsed mode of glow discharge source is available in some commercial instruments and can be beneficial in
the analysis of heat-sensitive samples, for reduction of sputtering rate.
5.1.2 Selection of spectral lines
For each analyte to be determined, there exist a number of spectral lines which can be used. Suitable lines
shall be selected on the basis of several factors, including the spectral range of the spectrometer used, the
analyte mass fraction range, the sensitivity of the spectral lines and any spectral interference from other
elements present in the test specimens. For applications where several of the analytes of interest are major
elements in the specimens, special attention shall be paid to the occurrence of self-absorption of certain
highly sensitive spectral lines (so-called resonance lines). Self-absorption causes nonlinear calibration
curves at high analyte mass fraction levels, and strongly self-absorbed lines should therefore be avoided for
the determination of major elements. Suggestions concerning suitable spectral lines are given in Table B.1.
Spectral lines other than those listed may be used, as long as they have favourable characteristics.
5.1.3 Selection of glow discharge source type
5.1.3.1 Anode size
Most GD-OES instruments on the market are delivered with options to use various anode diameters, with
2 mm, 4 mm and 8 mm being the most common. Some older instruments have one anode only, usually
8 mm, while the most commonly used anode in modern instruments is 4 mm. A larger anode requires larger
specimens and higher power during analysis; therefore, the specimen is heated to a greater extent. However,
a larger anode gives rise to a plasma of larger volume that emits more light, resulting in lower detection
limits (i.e. higher analytical sensitivity). Furthermore, a larger anode helps to mask inhomogeneity within
a surface layer. This can be an advantage depending on the application. In a large number of applications,
the 4 mm anode is a good compromise. However, in surface analysis applications it is rather common to
encounter problems of overheating of the specimens due to, e.g. surface layers of poor heat conductivity
and/or very thin specimens. In such cases, a smaller anode is preferable (typically 2 mm or 2,5 mm), even if
there is some loss of analytical sensitivity.

5.1.3.2 Type of power supply
The glow discharge source can be either a type powered by a direct current (DC) power supply or a radio
frequency (RF) type. The most important difference is that the RF type can sputter both conductive and non-
conductive specimens; hence this is the only type that can be used for, e.g. polymer coatings and insulating
oxide layers. However, it is technically simpler to measure and control the electrical source parameters
(voltage, current, power) of a DC type. Several commercially available GD-OES systems can be delivered
with the option to switch between DC and RF operation, but RF-only systems also exist. In short, there are a
very large number of applications where DC or RF sources can be used and several where only an RF source
can be used.
5.1.3.3 Mode of operation
Both DC and RF sources can be operated in several different modes with respect to the control of the
electrical parameters (current, voltage, power) and the pressure. There are several reasons for this:
— “historical” reasons (older instruments have simpler but functional power supplies, while the technology
has evolved so that newer models have more precise and easier-to-operate source control);
— different manufacturers have chosen different solutions for source control;
— there are some application-related issues where a particular mode of operation is to be preferred.
This document gives instructions for optimizing the source parameters based on several available modes
of operation. The most important reason for this is to make these instructions comprehensive so as to
include several types of instruments. In most applications, there is no major difference between these
modes in terms of analytical performance, but there are other differences in terms of practicality and ease
of operation. For instance, a system equipped with active pressure regulation will automatically be adjusted
to the same electrical source parameters every time a particular analytical method is used. Without this
technology, some manual adjustment of the pressure to achieve the desired electrical source parameters
is normally required. Alternatively, a method to correct for impedance variations by means of empirically
[7]
derived functions can be used, provided it is implemented in the software of the GD-OES systems.
NOTE In this context, what is known as the emission yield forms the basis for calibration and quantification as
[8][9]
described in this document . The emission yield has been found to vary with the current, the voltage and, to a
[7][10][11]
lesser extent, the pressure . It is impossible in practice to maintain all three parameters constant for all test
specimens, due to variations in the electrical characteristics of different materials. In several instrument types, the
electrical source parameters (the plasma impedance) can therefore be maintained constant by means of automatic
systems that vary the pressure during analysis.
6 Adjusting the glow discharge spectrometer system settings
6.1 General
Follow the manufacturer's instructions or locally documented procedures for preparing the instrument for use.
RF sources differ from DC sources in the respect that for several instrument models, only the applied
(forward) RF power can be measured, not the actual power developed in the glow discharge plasma. The
applied RF power is normally in the range 10 W to 100 W, but it needs to be noted that the RF power losses
in connectors, cables, etc. vary considerably between different instrument models. Typical power losses are
in the range 10 % to 50 % of the applied power. Furthermore, the possibilities to measure the additional
electrical parameters voltage and current in the plasma are more or less restricted due to technical
difficulties with RF systems, and several existing instrument models can only measure the applied RF power.
There is no difference between DC and RF concerning the possibilities to measure the pressure. However,
there are large pressures differentials in a Grimm type source, and pressure readings obtained depend on
the location of the pressure gauge. Some instrument models have a pressure gauge attached to measure
the actual pressure in the plasma, while others have a pressure gauge located on a “low pressure” side of
the source closer to the pump. Therefore, the pressure readings can, for several instruments, just be used

to adjust the source parameters of that particular instrument, not as a measure of the actual operating
pressure in the plasma.
For test specimens, calibration samples and validation samples, it is important to ensure before analysis
that once located in the glow discharge source there are no vacuum leaks. Special attention shall be paid on
the sealing between the sample and glow discharge source.
For the optical system, the most important preparation step is to check that the entrance slit to the
spectrometer is correctly adjusted, following the procedure given by the instrument manufacturer. This
ensures that the emission intensities are measured on the peaks of the spectral lines for optimum signal-to-
background ratio. For further information, see ISO 14707. For an optical system with array type detectors,
the corresponding control is to check that the wavelength calibration is correct, following the procedure
given by the instrument manufacturer.
The most important step in developing a method for a particular application is to optimize the parameters
of the glow discharge source. The source parameters shall be chosen to achieve three aims:
a) adequate sputtering of the test specimen, to reduce the analysis time without overheating the specimen;
b) good crater shape, for good depth resolution;
c) constant excitation conditions in calibration and analysis, for optimum accuracy.
Trade-offs are often necessary among the three specified aims. More detailed instructions on how to adjust
the source parameters are given in 6.2 and 6.3.
The settings of the parameters for detector sensitivity depend on the source parameters, but the procedure
is the same for all modes of operation of the source. This procedure is therefore only described for the first
mode of operation.
Similarly, the steps to adjust and optimize the source settings in terms of signal stability and sputter crater
shape are also similar in principle for all modes of operation. Therefore, these procedures are only described
in detail for the first mode of operation.
6.2 Setting the discharge parameters of a DC source
6.2.1 Constant applied current and voltage
6.2.1.1 General
The two control parameters are the applied current and the applied voltage. Set the power supply for the
glow discharge source to constant-current/constant-voltage operation (current set by the power supply,
voltage adjusted by pressure/gas flow regulation). Then set the current and voltage to the typical values
recommended by the manufacturer. If no recommended values are available, set the voltage to 700 V and the
current to a value in the range of 5 mA to 10 mA for a 2 mm or 2,5 mm anode, 15 mA to 30 mA for a 4 mm
anode or 40 mA to 100 mA for a 7 mm or 8 mm anode. If no previous knowledge of the optimum current is
available, it is recommended to start with a value somewhere in the middle of the recommended range.
6.2.1.2 Setting the parameters for detector sensitivity
Select test specimens with surface layers of all types to be determined. For all test specimens, run the source
while observing the output signals from the detectors for the analyte atoms. Adjust the high voltage of the
photomultiplier (PMT) detectors in such a way that sufficient sensitivity is ensured at the lowest analyte
mass fraction without saturation of the detector system at the highest analyte mass fraction. For array type

detectors (CCD, CMOS or CID), it may be necessary to adjust the integration time in the same way as the high
voltage for PMT. However, some instruments have a fixed integration time that needs no adjustment.
NOTE Some instruments allow to work in dynamic mode, where all measured intensities are converted into the
intensity, which would be measured at the lowest sensitivity (shortest integration time or lowest PMT voltage). In
this case, calibration and measurement of the samples can be done at optimal sensitivity. For this dynamic operation
mode to function, the ratio of the sensitivities needs to be determined as a function of integration time/PMT voltage
beforehand.
6.2.1.3 Adjusting the discharge parameters
For each type of test specimen, carry out a full depth profile measurement, sputtering it in the glow discharge
for a sufficiently long time to remove the surface layers completely and continue well into the base material.
By observing the emission intensities as a function of sputtering time (often referred to as the qualitative
depth profile), verify that the selected source settings give stable emission signals throughout the depth
profile and into the substrate. If this is found not to be the case, reduce one of the control parameters by a
small amount and sputter through the surface layers again. If the stability is still unsatisfactory, reduce the
other control parameter by a small amount and repeat the measurements. If found necessary, repeat this
procedure for several control parameter combinations until stable emission conditions are obtained.
NOTE Unstable emission signals can indicate thermal instability in the specimen surface layers; specimen cooling
is beneficial in this regard.
6.2.1.4 Optimizing the crater shape (optional)
If a suitable profilometer device is available, adopt the following procedure. Sputter a specimen with a
surface layer typical of the test specimens to be analysed to a depth of about 10 µm to 20 µm, but still inside
the surface layer. This is only possible for applications where surface layers of such thickness are available.
If no such specimen is available, use a steel or brass specimen. Measure the crater shape by means of the
profilometer device. Repeat this procedure a few times using slightly different values of one of the control
parameters. Select the conditions that give an optimally flat-bottomed crater. These conditions are then used
during calibration and analysis, provided that the stability of the emission conditions obtained in 6.2.1.3 is
not compromised. In some cases, there is a certain trade-off between these two requirements.
6.2.2 Constant applied current and pressure
The two control parameters are the applied current and the pressure. Set the power supply for the glow
discharge source to constant current operation. Then set the current to a typical value recommended by
the manufacturer. If no recommended values are available, set the current to a value in the range of 5 mA
to 10 mA for a 2 mm or 2,5 mm anode, 15 mA to 30 mA for a 4 mm anode or 40 mA to 100 mA for a 7 mm or
8 mm anode. If no previous knowledge of the optimum current is available, it is recommended to start with
a value somewhere in the middle of the recommended range. Sputter a typical coated test specimen, and
adjust the pressure until a voltage of approximately 700 V is attained in the surface layer.
Set the parameters for detector sensitivity as described in 6.2.1.2.
Adjust the discharge parameters as described in 6.2.1.3, adjusting first the current and, if necessary, the
pressure.
Optimize the crater shape as described in 6.2.1.4 by adjusting the control parameters. These conditions are
then used during calibration and analysis (optional).
Before sputtering a new specimen type, make a test run to ensure that the voltage has not changed by more
than 5 % from the previously selected value. If this is the case, readjust the pressure until the correct value
is attained.
6.2.3 Constant applied voltage and pressure
The two control parameters are applied voltage and pressure. Set the power supply for the glow discharge
source to constant voltage operation (voltage set by the power supply, current adjusted by pressure/gas flow

regulation). First, set the voltage to a typical value recommended by the manufacturer. If no recommended
values are available, set the voltage to 700 V. Sputter a typical coated test sample, and adjust the pressure
until a current is attained in the range of 5 mA to 10 mA for a 2 mm or 2,5 mm anode, 15 mA to 30 mA for
a 4 mm anode, 40 mA to 100 mA for a 7 mm or 8 mm anode in the surface layers. If no previous knowledge
about the optimum current is available, it is recommended to start with a value somewhere in the middle of
the recommended range.
Set the parameters for detector sensitivity as described in 6.2.1.2.
Adjust the discharge parameters as described in 6.2.1.3, adjusting first the voltage and if necessary, the
pressure.
Optimize the crater shape as described in 6.2.1.4 by adjusting the control parameters. These conditions are
then used during calibration and analysis (optional).
Before sputtering a new sample type, make a test run in order to ensure that the current is not altered more
than 5 % from the previously selected value. If this is the case, readjust the pressure until the correct value
is attained.
For analysis of very thin layers < 100 nm, it is recommended to test and evaluate all three modes described
above. There can be a small difference in the very short start-up of the discharge, affecting the analytical
results to some extent. In the constant applied voltage and current mode, the pressure is increased until
ignition occurs. The pressure must then be decreased to reach the selected current. In the constant applied
current and voltage mode, the voltage increases until ignition occurs, if the correct start pressure is set the
voltage rapidly reaches the set value with minimal pressure regulation. It is therefore important to adjust
the start pressure before ignition to a value such that the voltage and current values in the thin layer come
very close to those used for calibration of the instrument. A few trials on a sample with the correct type of
thin layer may be necessary. The purpose is to minimize changes in the discharge parameters during the
short time the nanolayer is sputtered. Detailed instructions are given in 6.4.2.
6.3 Setting the discharge parameters of an RF source
6.3.1 Constant applied power and pressure
The two control parameters are the applied power and the pressure. First set the applied power (forward
power) and adjust the source pressure to the values suggested by the manufacturer. If recommended values
are not available, set the applied power and pressure to somewhere in the middle of the ranges available for
the instrument used. Measure the penetration rate (i.e. depth per unit time) on an iron or steel specimen,
adjusting the power to give a penetration rate of about 2 µm/min to 3 µm/min.
Set the parameters for detector sensitivity as described in 6.2.1.2.
Adjust the discharge parameters as described in 6.2.1.3, adjusting first the applied power and, if necessary,
the pressure.
Optimize the crater shape as described in 6.2.1.4 by adjusting the control parameters (optional).
Remeasure the penetration rate on the iron or steel specimen and adjust the applied power, if necessary,
to return to about 2 µm/min to 3 µm/min. Repeat the cycle of power and pressure adjustment until no
significant change is noted in the penetration rate or crater shape. Note the power and pressure used in
units provided for the instrument type. These conditions are then used during calibration and analysis.
6.3.2 Constant applied power and DC bias voltage
The two control parameters are the applied power and the DC bias voltage. First set the applied power
and adjust the source pressure to attain a DC bias typical of the values suggested by the manufacturer.
If recommended values are not available, set the applied power and DC bias voltage to somewhere in the
middle of the range commonly used for depth profiling of metal specimens. On instruments equipped with
active pressure control, this can be achieved automatically. Measure the penetration rate (i.e. depth per unit
time) on an iron or steel specimen, adjusting the power to give a penetration rate of about 2 µm/min to

3 µm/min. Note that this procedure is only applicable to conducting surface layers, since the DC bias voltage
cannot be measured for a specimen with a non-conducting surface layer.
Set the parameters for detector sensitivity as described in 6.2.1.2.
Adjust the discharge parameters as described in 6.2.1.3, adjusting first the applied power and, if necessary,
the DC bias voltage.
Optimize the crater shape as described in 6.2.1.4 by adjusting the control parameters (optional).
Remeasure the penetration rate on the iron or steel specimen and adjust the applied power, if necessary, to
return to about 2 µm/min to 3 µm/min. Repeat the cycle of power and DC bias voltage adjustment until no
significant change is noted in the penetration rate or in the crater shape. If this is not the case, readjust the
DC bias voltage until the correct value is attained. Note the power and DC bias voltage used in units provided
for the instrument. These conditions are then used during calibration and analysis.
6.3.3 Constant effective power and RF voltage
The two control parameters are the effective power and the RF voltage. Constant effective power is defined
here as the applied power minus the reflected power and the “blind power” measured with the specimen
in place but without plasma (vacuum conditions). The RF voltage is defined here as the RMS voltage at the
coupling electrode (see note below).
Set the power supply for the glow discharge source to constant effective power/constant RF voltage operation.
First set the power to a typical value recommended by the manufacturer. If no recommended values are
available, set the RF voltage to 700 V and the power to a value in the range of 10 W to 15 W for a 4 mm
anode, 5 W to 10 W for a 2 mm anode, to give an example. If no previous knowledge of the optimum power is
available, it is recommended to start with a value somewhere in the middle of the recommended range.
Set the parameters for detector sensitivity as described in 6.2.1.2.
Adjust the discharge parameters as described in 6.2.1.3, adjusting first the effective power and, if necessary,
the RF voltage.
Optimize the crater shape as described in 6.2.1.4 by adjusting the control parameters. Select the conditions
that give an optimally flat-bottomed crater. These conditions are then used during calibration and analysis
(optional).
NOTE In order to determine the RF RMS voltage, it is essential to include the offset caused by the DC bias voltage,
which is not possible to measure at the coupling electrode when non-conductors are sputtered. However, when only
relatively thin (<100 µm) non-conductive layers on a conductive specimen are analysed, the offset can be estimated
[12]
and the amplitude of the RF voltage multiplied by 1,22 can be used as a good estimate of the RMS voltage . For
[13]
thick non-conductors, more complex calculations must be carried out . However, analysis of thick non-conductors is
outside the scope of this document.
6.4 Minimum performance requirements
6.4.1 General
The instrument needs to conform to the performance specifications given in 6.4.3 and 6.4.4 below, for
applications to very thin layers < 100 nm also to 6.4.2.
NOTE Setting up for analysis commonly requires an iterative approach to the adjustment of the various
instrumental parameters described in this document.
6.4.2 Control of lamp cleanliness and start-up performance
For applications to very thin surface layers < 100 nm that may be sputtered in just a few tenths of a second,
the stability at the start-up is of utmost importance. This is also closely linked to the lamp cleanliness. Here
are instructions how to verify that the lamp start-up performance is good enough for very thin film analysis.

Before performing the test, run the lamp at least 2 000 s with e.g. a steel sample. This is in order to remove
as much as possible contamination of the lamp interior (primarily on the anode walls) prior to analysis.
Prepare a steel sample by dry grinding with a new paper of mesh 180 – 320. Do not use wet grinding and/
or surface cleaning with a degreasing liquid. Place the sample on the lamp immediately after grinding and
start a depth profile analysis. Run the analysis 50 s – 100 s at the data acquisition speed to be used for the
nanolayers. Check first that the discharge has been stable throughout the analysis. Plot the intensity vs time
the first 10 s of the Fe channel to be used in the analysis, see Figure 1. Check that the Fe intensity has reached
50 % of the intensity at 10 s in < 0,5 s. If this is not the case, check the stability of the electrical parameters
and the pressure at start-up, if necessary, make adjustments and repeat the test. If the performance specified
above cannot be attained, the instrument is not suitable for nanolayer analysis.
Key
X time, s
Y intensity, voltage
1 Fe 372 nm
2 Fe 249 nm
3 50 % of 10 s intensity level
Figure 1 — Risetime of Fe spectral lines
In case the criteria for start-up performance fails to meet the specifications above, proceed as follows to
investigate the problem. First, repeat the measurement with a freshly surfaced sample, making sure that
the sample is not dropped from the lamp after completed measurement. Second, repeat the measurement
immediately, now in the same spot as the first measurement. The result should look similar to that shown
in Figure 2, with a risetime exceeding the < 0,5 s limit. If this is not the case, the measurements shall be
terminated and have the instrument serviced before proceeding.
If a risetime < 0,5 s is observed in the second measurement but not in the first, the lamp is probably
contaminated. Replace the anode and inspect
...