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Editorial information
nanotec afm letters is published by Nanotec Electronica S.L.
Centro Empresarial Euronova 3, Ronda de Poniente 12, 2ºC. 28760 Tres Cantos, Madrid. Spain.
Tel. +34-91 804 33 26 // Fax. +34-91 804 33 48.
For any question please contact at: sales@nanotec.es

Dear friend of Nanotec,
Mr. Rafael Fernandez
Nanotec General Manager
After many years of developments, we have finally released WSxM
3.0, and launched the new WSxM 5.0 version. We have great plans
for this new version of our software, and we hope that you will continue
supporting us with your feedback to keep developing the best SPM
software.
As you probably know, the world economical situation has affected the science community.
To face this point, Nanotec has launched a new idea which can help the finances of the AFM researchers
in the world: After detecting that there are many scientists with old, bad, or even not working
controllers for potentially useful AFM heads, we have developed a cost-effective solution to “rejuvenate”
those heads, by connecting them to our powerful Dulcinea controller. The power of WSxM’s
microscope control part will be this way helping your old head to get cutting-edge data again (find
more information in page 28).
Also, our R&D department has been working, in collaboration with the highest level SPM
laboratories (see Acknowledgements), in many new features, including software developments,
new AFM heads, new options, etc. In order to get you to know the new developments we are involved
on, we have launched this magazine, which I hope will be interesting for everybody. We have
tried to organize the developments in the index in different sections, starting with those that you
can already use for free if you just upgrade your software. Second, we have indexed those that are
possible additions to your Cervantes FullMode AFM, then we have listed those useful if you own a
Dulcinea for controlling a third-party AFM/STM, and finally those that are interesting to you if you
own a non-Nanotec AFM, and would like to add some of these new developments to it.
The presented developments are in different state of evolution, so please contact us for
questions about any of them. Also, we continue with our “open developments” policy, so if you find
a development that is interesting in this list, remember that we can offer you a prototype so yoy will
be among the first ones to enjoy it, and if you do not find the feature you would like, let us know
and we will evaluate the possibility of including it in our plans or collaborating with you in order to
make it possible.
3

free improvements for
all nanotec users
new modes
Frequency Modulation.............................8
Easy-to-use WSxM................................9
General Spectroscopy Imaging
(acquiring volumes of data)...................10
Nanomanipulation.................................11
Atom Tracking........................................11
new / improved features
Generic Curves acquisition...................12
Cantilever K estimation.........................12
Automatic Drift correction......................13
XY Tilt....................................................13
Friction decoupling...............................14
Real-time view of amplitude, phase, X,
and Y......................................................15
Top image: Integrated circuit imaged with closed-loop. Nanotec Electrónica S.L.
index
cervantes fullmode
afm new options
new modules
WSxM Gold Package............................17
Lanza AFM Head.................................18
High Vacuum AFM/STM........................20
Variable field MFM...............................20
Variable temperature............................21
continues on the next page >>
5

cervantes fullmode
afm new options
scanners
Closed loop...........................................22
XY inertial scanners..............................22
Ultra long scanner.................................23 free improvements for
improved modules
Dual lock-in (KPM, multifrequency, harmonics,
etc)...........................................23
2 MHz bandwidth..................................24
Large samples......................................24
Variable gain IV.....................................25
6
dulcinea controller
new options
DLPCA-200 compatibility.....................27
dI/dV module.......................................27
Laptop control......................................27
other spm mechanics´
owners
Inertial Box...........................................29
3rd party interfaces..............................29
reference list..........................................30
acknowledgements............................32
all nanotec users
Since the creation of Nanotec Electronica, our software department have been working to provide
the SPM comunity with the most flexible and complete SPM softwares. WSxM is a user-friendly,
reliable and powerful tool to study samples at the nanoscale and provide new insights into the capabilities
of the SPM technique for data acquisition and processing.
During the last few years, Nanotec has been looking for new and more advanced features to
improve the functionality of WSxM and provide the best solutions to our customers.
The latest developments introduced here will expand the possibilities of your Cervantes AFM and
Dulcinea Electronics and will provide new solutions to your research.
Upgrade now your WSxM Software (www.nanotec.es) to the last WSxM 5.0 Develop version and
start enjoying the latest Data Acquisition (with Nanotec Cervantes FullMode AFM or Dulcinea Controller
only) and Processing SPM features from today.
Top image: Dulcinea electronics
7

Frequency Modulation
Because Ultra High Vacuum (UHV) requires much greater control
than ambient conditions, the standard dynamic modes are not
accurate enough. Therefore Nanotec has integrated the Frequency
Modulation technique as a possibility in the Dulcinea Control
system. For this mode of operation, three feedbacks should be closed
and stabilized simultaneously. Also, very fine resolution is needed
for working in the lowest possible amplitudes. The different
dynamic mode menus of WSxM have been adapted to the possibility
of performing Frequency Modulation, and now our users are
applying it not only in UHV, but also in ambient conditions and liquids
so they can get much better results.
Sample: octadecylamine (18 carbon atoms, linear)
deposited on mica by immersion in a solution 15 mM
in chloroform, dried and aged for several weeks.
Images courtesy of J.J. Benitez Institute of Materials
Science of Seville
8
Topographic UHV NC-AFM image of the
Si(111) 7x7 surface
Morita Lab. Osaka Univ. Japan
True atomic resolution in liquids. Mica
(001) Author: David Martínez - Martin and
Julio Gómez. New Microscopies Lab.
(UAM)
Easy-to-use WSxM: WSxM adquisition Wizard
At Nanotec, we are always focusing in offering not only the best quality products, but also the best
user experience. In that direction, we combine the continuous addition of new options and features,
with the continuous upgrade of the software interface with the goal of getting it as easy to use as
possible. With that aim, we have added the option of linking P,I parameters, the automatization of XY
gains, improvements in changes of Z gain for avoiding any possibility of crashing the tip, and advanced
sections in many of the menus to separate those parameters rarely used from those that are
more important in each menu.
Also, we have added automatic calculation of scales in the channels, and automatic search for an initial
set point in the approach.
In addition, we are developing a new one-click one-image interface, which will make the acquisition
of an image with WSxM as simple as the creation of a data DVD for the beginners. Of course, that
will not mean the lack of options, as the user will always be able to switch to the classic interface for
using the full set of features that WSxM provides.
The new Wizard of the Full-
Mode Cervantes AFM will
allow to easily aquire an
image in less than 15 minutes
from scratch
9

General Spectroscopy Imaging
(acquiring volumes of data)
With the new General Spectroscopy Imaging menu, you will be able to perform any kind of spectroscopy
maps over your image. This includes volumes of any magnitude you can measure with your
Dulcinea controller, like force, current, or frequency drift. The usual freedom of choice you find in
other Nanotec modes is specially interesting in this mode, allowing you to measure any volume you
can think about, selecting even the shape of the spectroscopy curve. Due to the complexity of the
acquired data, a full set of data processing options has also been developed for its proper treatment.
10
Screen capture showing the data process
of a Force Volume. Experiment on a virus.
Author: Carolina Carrasco. New
Microscopies Lab. UAM
Nanomanipulation
One of the main differential features of AFM is
the capability to interact with the surface that is
being measured, in order to create changes at
the choice of the researcher. At Nanotec, we
have recently developed a Nanomanipulation
menu, that allows interactive and fast nanomanipulation
by presenting an informative graphical
interface, which indicates the effects of your
actions in the monitored signal in every moment,
as well as allows you the fast execution
of custom designed lithographic scripts. Using
this menu, we hope you will be able to fully
control your nanomanipulation experiment for
the fast creation of the structures you need.
Final topographic NC-AFM image of the process of lateral manipulation
of substitutional Sn adatoms in the Ge(111)-c(2x8) surface
at room temperature. Morita Lab. Osaka Univ. Japan.
Atom Tracking
A new menu for Atom Tracking has been developed.
This feature was required for Ultra
High Vacuum experiments, in order to ensure
that the studies of the interaction between the
AFM tip and a particular atom were always performed
in the same place above the atom. It is
also a perfect system for fast drift calculation.
The atom tracking technique is based on the
displacement of the tip in circles around the selected
atom, calculating and following its movement.
After its development in collaboration with the
University of Osaka, we encourage all Cervantes
users to apply it to ambient conditions
experiments. In principle, this concept would
be applicable to any quasi-spheric object, regardless
of its size.
Movement of the tip during Atom Tracking experiment. Tracking
resolution: +/-0.2Å Test performed by Sugimoto in Morita Lab
Osaka Univ. Japan.
11

Generic Curves acquisition
It is very important for AFM to extract one dimensional spectroscopy data. So, any AFM will allow the
user to perform Force vs. Distance curves (FZ), Current vs. Distance curves (IZ) and Current vs.
Voltage curves (IV). At Nanotec we decided not to limit the spectroscopy experiments to those standard
measurements, but to leave it completely open. So, besides the specialized menus for acquiring
the standard spectroscopy curves, we have developed the Generic Curves Acquisition menu, which
allows the performance of any spectroscopy experiment, varying one magnitude (between the 12
available including 3 rear user output BNCs) and recording other magnitude (between the 16 available
including the 4 rear user input BNCs). This allows performing a huge number of combinations, including
for example, Phase vs. Excitation Frequency curves.
Cantilever K estimation
In order to convert the forces read by the system into physical units
(nN/pN), it is necessary to provide the cantilever force constant (K) to
the system. Before this development, the user supplied this information
based on the data from the cantilever manufacturer or from his own estimations.
The data given by the manufacturer usually has too large an
error, which makes it useless for precise force measurements, and the
estimations are tedious for the user without software assistance.
So, after some discussion in the NanotecForum, it was suggested that
the Sader method was a nice estimation. The Nanotec software team
thought it was a nice idea to facilitate its use to WSxM users, and made
the necessary development so estimation of the cantilever K is now an
easy thing.
Force calibration menu (including K estimation) Cantilever Nanosensor of 40 N/m
Automatic Drift correction
An inherent problem to Scanning Probe Microscopy is the
thermal drift. Temperature variations at the microscope environment
cause a small drift between the tip and the sample.
Even with the Nanotec piezoelectric scanners, carefully designed
to minimize the drift, this effect is a problem that affects
the measurements and makes them less accurate than they
should be.
From long ago, in the Nanotec systems, the user had the
possibility of correcting drifts during movie acquisition. Everytime
a new image was acquired, the drift was calculated, and
compensated before starting with the next image. This method
has shown very good results allowing many hours of video
even with atomic resolution in Ultra High Vacuum environments.
Recently, Nanotec has expanded the possibilities of the drift
correction in several ways. First, we have created a new menu
that allows activating the drift correction in any moment (not
only during the acquisition of movies); second, using the capabilities
of Dulcinea, we have included Z drift correction, allowing
to use the highest resolution gain for long times; and third, we have developed continuous XY
drift correction, correcting the drift even inside the image or during spectroscopy experiments.
XY Tilt
Drift correction menu access
In very controlled environments, like Ultra High Vacuum (UHV) at Low Temperature, in which there
is not movement of the atoms, sometimes it is useful to stop the scan, remove the feedback that
keeps the tip-sample distance constant, and move the tip over the sample dynamically, interactively
and fast. This possibility was partially there in Nanotec systems, as you could stop the scan, stop the
feedback, and move the tip with the mouse, but it was not as useful as it should because of the
sample tilt.
12 13

With XY tilt correction, the WSxM software
calculates the tilt of your sample in order to
take it always into account. As soon as WSxM
corrects it, the system will start working in the
same way as if there was not any tilt between
the sample surface and the XY movement of
your scanner, so you will be able to move freely
over the surface with the mouse without caring
about the sample inclination.
This correction is also useful for systems in
UHV or ambient conditions (without Low Temperature),
not for removing the feedback
(which is not recommended in general), but for
smoothing the feedback work, as it will not see
the tilt, and will be better in following the real
objects on the surface easily without the need
of changing the scan angle.
Auto-tilt adjustment
Friction decoupling
It is well known that the AFM allows the
measurement of the friction of the tip with the
sample. This is very useful for chemical
distinction and for friction studies at the
nanoscale. For detecting the friction, the AFM
uses a four-quadrant photodiode, that separates
Normal Force and Lateral Force (see figure
above). The horizontal displacement of the
laser with respect to the photodiode indicates
the torsion of the cantilever, which is directly related
to the friction between the tip and the
sample.
As the alignment of the mechanical components
working in the measurement (laser, cantilever
and photodiode) will never be 100%
perfect, a part of the normal force (usually orders
of magnitude higher than the lateral force)
will be induced in the lateral force
measurement. Nanotec has developed a process
to calculate this error and to correct it in
real time, so the user can measure the friction
free of any coupling.
Coupling of the
Normal Force and
the Lateral Force
Real-time view of amplitude, phase, X, and Y
Same experiment
after decoupling
For working in dynamic modes, we use an internal lock-in in Dulcinea (the Dynamic Force Modulation
Board) to separate the X and Y components of the incoming signal (usually normal force), and then
we tune the frequency and phase of the lock-in, so we work in the resonance frequency, and X represents
the amplitude and Y the phase.
This assumption (X=amplitude; Y=phase) is correct for small variations in the resonance frequency
of the cantilever when approaching to the sample. As usually there are, the mostecommended option
is to use the PLL (“Phase Lock Loop”) mode for frequency shift correction. The PLL mode will change
the working frequency in order to be always in resonance, and making the phase (Y) equal to zero.
Up to now, the user could only see X and Y components, but for working in Amplitude Modulation
mode without PLL, it is sometimes interesting to be able to map also the real Amplitude and Phase,
as well as to feedback the system in Amplitude instead of X. We have recently improved WSxM software,
so you can have the four signals simultaneously mapped in real time, and you can save them
all together. This feature also expands for the second dynamic board, allowing the most fundamental
experiments about the dynamic modes.
14 15

cervantes fullmode afm
new options
Nanotec Cervantes FullMode Atomic Force Microscope (AFM) is a cost-effective tool widely used to
characterize samples and perform experiments at the nanoscale. Its various configurations allow not
only imaging samples with atomic precision but also the study of magnetic, electronic and mechanical
properties at the nanoscale, making it a powerful tool for physicists, chemists, biologists and
engineers willing to characterize their samples.
Its robust design provides strong mechanical stability to ensure high imaging resolution, and its semiautomated
and open design allows scientists to exploit the capability of SPM to its maximum for both
research and academic purposes. It has been widely used in applications ranging from the study of
biologic molecules in a liquid environment to the study of magnetic domains in a hard disk or the
measurement of conductivity of carbon nanotubes.
Cervantes FullMode AFM is under continuous development to offer the best solutions and widen the
range of applications available. Nanotec Electronica has implemented innovative AFM modules that
will allow Cervantes users to add new features to the existing experiments.
Top image: Integrated circuit imaged with closed-loop. Nanotec Electrónica S.L.
WSxM Gold Package
In 1998, Nanotec Electronica launched the first version of WSxM software. At that moment, we decided
to let WSxM free for downloading for our users, so they could update to the new developments
at any moment, but also for anyone wanting to use the WSxM software for data process in public research
applications. Our development team has also kept a constant effort in adapting WSxM to be
able to read any SPM file format that has been appearing from then on. This approach, together with
the high quality of the software, has made WSxM the most popular SPM data processing software
in the world.
But during this time we learned that there was frequently
a lack of training for the new users
approaching WSxM, which would be important to
work on. For this reason, we have developed a
set of videos for learning both abouth the basics
of SPM and about the principles of WSxM. We joined
this development with a license allowing the
use of WSxM for profit applications, creating this
way the WSxM Gold Package, with the hope that
it will help WSxM users and SPM trainers.
WSxM Gold Package.
WSxM Tutorial: Multiple Dynamic Zoom
WSxM Gold Package
A Primer on SPM hosted by Prof. Ron Reifengerder
WSxM Gold Package. WSxM Tutorial: Multiple profile
16 17

Lanza AFM Head
This new AFM head prototype foresees as the next step for Nanotec AFM head
technology. Improving the quality and stability of the laser to reach 12 μm spot size
on the cantilever, with an easier to use, and even increased mechanical stability
against the standard Nanotec AFM head design, the results of the first prototype
have been much better even than expected, obtaining the highest resolution images
of biological samples, as well as very nice atomic periodicity in air and true atomic
resolution in liquids.
Lanza Head First Prototype
and the atoms obtained in liquids
Interview with David Martínez:
The roadwork to obtain true atomic resolution in liquids
The new AFM head design, which is the result of a collaboration between David Martinez-Martin
and Julio Gomez-Herrero with Nanotec, comes to the fore as the next step
for Nanotec AFM technology. With this new prototype and Dulcinea control unit David
has been able to obtain state of the art (see results of Hirofumi Yamada’s and Andreas
Engel’s groups) images of mica (001) in liquids with true atomic resolution.
Question: How do you get this kind of high resolution images?
Answer: I work with a technique which is called Frequency Modulation (FM-AFM or just FM). It is a
very well known mode to work in vacuum but currently it is starting to be a very promising mode also
in liquids.
Question: When and why did you start to use Frequency Modulation?
Answer: I started about three years ago, at the beginning of my PhD. As a first step of my PhD I built
up the first high vacuum system in Spain with an AFM inside. Due to the low pressure (high vacuum)
the damping of the cantilever is very small which implies high Q factor and high sensitivity. The dark
side are long transients when the cantilever amplitude changes, that makes difficult to obtain images
using the classical amplitude modulation, much easier to use in terms of electronic and software requirements.
FM uses the frequency as the main feedback parameter and utilizes an amplitude feedback
to avoid the ringing associated to the high Q. This issue makes FM a more proper method than
the standard amplitude modulation (AM) mode for high vacuum. As I said, one of the advantages of
working in vacuum is that the sensitivity of an AFM is much higher than in air, for this reason I use
this system to study with high sensitivity long range interactions at the nanometer scale.
Question: When did you decide to make the big jump from vacuum to liquids?
Answer: A liquid environment is the common media for a big range of biological systems and I have
been always very interested on these kind of systems. On the other hand, the New Microscopy Laboratories
had extended experience doing biophysics with AFM, so we thought it could be interesting
to combine the experience of Carolina Carrasco and Pedro Jose de Pablo in biology and my expertise
in FM. And now I can say that it was a very successful
idea!.
Question: Why does FM work so good in liquids?
Answer: First of all I would like to clarify that,
even though FM is the regular way to measure
in vacuum, that does not mean at all that this
technique is not appropriate for air ambient
conditions or liquids. Actually this way to work
gives you much more control on the relevant
parameters of AFM than standard techniques,
but it requires more and more complex
feedback systems and also a bigger
knowledge about how to operate
the AFM. For instance, instead of
the single feedback loop that is
used in conventional amplitude
modulation or contact mode, FM
needs three feedback loops.
If your question is why FM allows
to reach true atomic resolution in
liquids what I can say is that the answer
is still under discussion, but probably
it is related with the fact that the low
quality factor of the cantilever in liquids is
somehow compensated for the screening of
Van der Waals forces due to the liquid. This together
with a small oscillation amplitude of the
cantilever (much smaller than oscillation amplitude
in Ultra high Vacuum) allows to detect
short range interactions.
Question: You collaborated with Nanotec in
the construction of the vacuum AFM, and then
also with the new Lanza head. Were you never
afraid of working on a prototype microscope?
Answer: On the contrary, both times it was exciting
to set up a unique system. I knew it was
more difficult and risky, but it was also more
satisfying. These projects have a lot of parts
David Martínez is Ph. D. student in the New Microscopies Laboratory (NML) of the Madrid Autonoma University (UAM). Top image: Mica (001) Author: David Martínez - Martin and Julio Gómez. New Microscopies Lab. (UAM)
and just one person is not able to do everything.
The collaboration of Nanotec was fundamental
for me, and finally the result deserves
the efforts.
Question: After the experience of collaborating
with Nanotec, what is your impression?
Answer: I consider very important to perform
applied research in the University. The systems
that we have developed together with
Nanotec will not only allow me to perform
the experiments that I need for
my research, but they will soon
help many other researchers
worldwide. I will be very happy to
continue collaborating with Nanotec.
Question: Finally, what other
people helped you to obtain such
nice results?
Answer: I have to thank to many people
that helped me during these years. Of
course Julio Gomez-Herrero, who is my PhD
advisor and the person who taught me all the
secrets about AFM along with Cristina Gomez-
Navarro. I also learnt a lot about FM during my
time in Germany thanks to Franz Giessibl, one
of the leading persons in the field of AFM. The
time that I spent in the laboratory of Julio Fernandez
at Columbia University in NYC and in
the laboratory of Miquel Salmeron in Berkeley
was very important as well. I also would like to
thank to Mariano Carrion, who introduced me
to the world of bio AFM, and finally I would like
to thank to Pilar Iñiguez de la Torre, who
cheered me up a lot and helped me to start
these projects.
18 19

High Vacuum AFM / STM
When needing to work in clean or dry
environments, like for highest resolution electrostatic
measurements, the environmental
control available in
the Cervantes AFM
could be not enough,
and vacuum environment
could be needed.
Working in
vacuum has several
clear advantages
against working in
ambient conditions:
the quality factor (Q)
High Vacuum System.
Nanotec Electronica S.L.
of the cantilever increases
naturally, offering
much higher
resolution in dynamic modes; the liquid layer
present always in ambient conditions disappears,
allowing more precise studies of electrostatic,
magnetism or adhesion; and finally the
environment is much cleaner, so you do not
have to worry about your sample getting dirty
with dust particles during long time measurements.
The cleanest environment for such problems
is the Ultra High Vacuum (UHV), but it is
well known that UHV systems are big, expensive
and complex, and require extensive tedious
maintenance work, combined with a long
time for sample / tip changing.
In Nanotec Electronica, we have designed the
best midway solution: An affordable High Vacuum
AFM / STM, based on the Cervantes
mini-platform FullMode AFM, that allows
reaching 10 -5 torr regime in about 15 minutes.
Variable Field MFM
Nanotec Cervantes AFM has always been especially
suitable for Magnetic Force Microscopy
(MFM) studies, but it has been always
based on measuring the magnetic properties
of the sample without external applied magnetic
field. Now, we have designed a new model
of MFM, which allows the study of the magnetic
response of the samples while applying
different magnetic fields.
The new Variable Field MFM allows applying
two different kinds of magnetic fields: perpendicular
to the sample, or parallel to the sample.
The new design with amagnetic components
allows maintaining the highest stability and resolution
of Cervantes AFM. Combined with the
drift control possibilities of WSxM, it gives you
the power to study the dynamics of the magnetization
/ demagnetization process with the
maximum precision.
Variable Field System. Nanotec Electrónica S.L.
Variable temperature
For many experiments, it is good to heat the sample in a controlled way, in order to understand the
properties of the sample at different temperatures. For SPM, it is important to be extremely careful
when heating the sample for several reasons: the heat could increase the thermal drift to a level in
which the images are not reasonably good, the heat could affect the piezoelectric components, and
depolarize them, so the system would stop working, and the heat could affect the sticky material that
is used to keep the different components of the AFM together, causing it to malfunction.
At Nanotec Electronica, we have designed a new add-on for temperature control, which allows the
change of temperature from ambient temperature up to more than 150ºC, varying it simultaneously
in the tip and the sample, minimizing the thermal drift and with a design that isolates the piezoelectric.
Nanotec Variable Temperature System
20 21

Closed loop
The SPM technology is based on the use of piezoelectric material, which is deformed almost linearly
with a given voltage. This incomplete lineality is especially noticeable near the borders of the scan
area of the scanner, and shows up in several
effects, like the distortion of the image or the
inaccuracy when zooming to a smaller region
from a bigger one. At Nanotec Electronica we
have designed a closed-loop system, compatible
with the previous hardware (for Cervantes
AFM and Dulcinea users). Based on
the use of strain gauges, the closed-loop
measures the real displacement of the piezoscanner,
correcting all the problems derived
from that piezo non-linearity. Its high resonance
frequency, humidity resistance and fiability
makes it the best option for accurate
measurements, especially under liquid environment.
XY inertial scanners
Open Loop
Simple XY tip-sample positioning is an important issue if you want to
position the tip over a particular place of the sample, which you can
locate with optical microscopy. If your experiments require ambient
control, you will also need a system that can be controlled with software.
Nanotec Electronica has designed a new model of scanners,
compatible with any Dulcinea-based Nanotec AFM.
This new model of scanners allows sub-micron precision positioning
of the tip in any position of the sample, with full control in WSxM.
Closed Loop
Integrated circuit imaged without closed-loop and with closed-loop. The
differences in non-linearity are easily appreciated, mainly in the borders
of the scan area
Coarse XY motion menu
Ultra Long Scanner
Even though the AFM technique is normally used for measuring small surfaces, everyday it is more
common to find applications in which the capabilities of SPM are useful for bigger surfaces. So, we
have reviewed the design of our long scanner (70 µm) thinking in these applications, reaching to a
new model that, in the first prototypes, was scanning more than 140 µm in opened loop and more
than 100 µm in closed loop operation.
Dual lock-in (KPM, multifrequency, harmonics, etc)
Thinking of KPM
experiments, we
WSxM EFM / KPM Menu
have developed
a special menu with the necessary automatic
adjustments to start measuring as fast as
possible, without the need to adjust all the
possible parameters before starting the
measurement, but starting with a good suggestion
from the software and then fine tuning
the parameters for the needs of the
particular experiment.
We have developed a complementary Dynamic Force Modulation Board.
This board is clock-synchronized with the first one, allowing the performance
of dual frequency experiments. This means that while the first
lock-in is getting data in the resonance frequency of the cantilever, the
second lock-in can be working at a completely different frequency,
allowing multifrequency experiments, lock-in in harmonics or in a completely
different frequency as it is needed for Kelvin Probe Microscopy (KPM)
experiments, that allow to know the local surface potential on the sample.
KPM in Self Assembled Monolayer (SAM)
M.Paradinas, L.Garzón, C.Munuera, C.Ocal “Combined Scanning Probes
Investigation of SAM-based Heterogeneously functionalized surfaces”. Institut
de Ciencia de Materials de Barcelona (ICMAB-CSIC)
22 23

2 MHz bandwidth
The bandwidth of the AFM is very important for
several applications. On one hand, the cantilever
manufacturers are increasing the resonance
frequency of their cantilevers, and on
the other hand, studies at harmonics or other
higher frequencies are getting popular. So, for
all the new customers of Nanotec Electronica,
we will increase the bandwidth of the system
to 2MHz from the current 1MHz bandwidth.
Frequency Spectrum of a Silicon Cantilever (k = 40 N/m)
HOPG Image acquired in Dynamic Mode with a Silicon Cantilever
(K = 40 N/m) oscillating at its 2nd oscillation mode
Large samples
Nanotec Large Samples stage
In Nanotec Electronica we know that sometimes
the maximum stability of the most compact
design is not compatible with measuring
all kinds of samples we would like to measure.
As we got the request from a few of our customers
to measure samples bigger than the
possible sizes for the standard Cervantes AFM
(1 x 1 x 0.3 inches), we
have designed new AFM
models making it possible
to increase the lateral
size up to 3 inches
diameter and the maximum
height of the sample
up to 1 inch. After
that, we have ensured
the stability, by using our
standard atomic periodicity
quality control.
Nanotec Large Samples
AFM head
Variable gain IV
For measuring local conductivity on the surfaces, it is necessary to apply a voltage difference between
the tip and the sample, and to measure the current flowing through an IV converter. The design of
the Nanotec cantilever holder is prepared for bias voltage application by default, but the measurement
of the current requires an add-on which is the IV converter. We wanted a new IV model, optimized
for current mapping and allowing a good set of available gains. The old model from Nanotec was
getting the current from the sample through the piezo, to be converted in voltage in the IV electronics,
attached to the platform of the microscope, and with fixed gain.
One of the improvements in the new model is to allow gain selection.The new Variable Gain IV converter
features a set of four software selectable gains, allowing a bigger range of current to be measured,
and the finest resolution for low currents. The second improvement was to design a specific
sample holder for conductivity, that avoiding to wire the signal together with the piezo signals, allows
the measurement of current maps with the highest quality.
Nanotec Variable-Gain IV converter
Metallic La 0.7 Sr 0.3 MnO 3 (LSMO) thin films grown by a chemical solution
deposition (CSD) process on a SrTiO 3 substrate. These films have
been developed through a new process leading to insulating epitaxial
(Sr,La)Ox nanodots at the surface.
Images courtesy by: C.Moreno, M. Paradinas, C.Munuera, X.Obradors
and C. Ocal. Institut de Ciència de Materials de Barcelona ICMAB-CSIC
24 25

Dulcinea controller
new options
The flexibility and power of Dulcinea Control System is based on the combination of Dulcinea Electronics
and the M6701 Innovative Digital Signal Processor, all controlled by the powerful WSxM SPM
Software.
Dulcinea Control System forms the core of the versatility of Cervantes FullMode AFM, allowing many
different modes of operation from Jumping Mode to Phase Lock Loop (PLL) or Lithography, but it
has also proven to be a robust and powerful Control System not only for Cervantes AFM but also for
other SPM systems available in the market.
We introduce herein Nanotec new developments for all Dulcinea users, which will increase even
more the versatility of your SPM system. The new Dulcinea modules will specially benefit those willing
to get the most of their STM and UHV-STM system.
DLPCA-200 compatibility
DLPCA-200 is a very popular IV used extensively
by researchers using Ultra High Vacuum
Scanning Tunneling Microscopy. We have developed
an easy and user-friendly interface, so
Dulcinea users can work easily with this IV,
using WSxM to select between all its options.
Variable-Gain Low Noise Current Amplifier DLPCA-200
Laptop Control
dI/dV module
Conductance (dI/dV) maps are a very popular
technique between STM users. Up to now, for
performing dI/dV maps, you needed an external
lock-in, and interfacing it with the Dulcinea
electronics. After several tests, we found out
that the Dynamic Force Modulation Board
(standard for AFM) is also very useful for STM
users, allowing them to easily perform conductance
maps, simultaneously with the topography
and current.
Dynamic Force Modulation Board
For some environments, it can be extremely useful to have a versatile AFM that can be easily moved
from one location to another. Up to now, that meant moving a standard computer, which is heavy
and difficult to transport together with the other components of the AFM. We have found out the way
to control the microscope using a laptop computer, reducing the logistic problems for these applications.
26 27

Other SPM
mechanics owners
The open arquitecture and modular design of Dulcinea Electronics facilitates interfacing with any
other AFM/SNOM/STM system available in the market providing not only a huge range of measuring
modes (from contact mode to nanomanipulation or Frequency Modulation) but also the high precision
and quality required for Ultra High Vacuum experiments.
Nanotec will study the technical requirements of your SPM head and will advise of the best solution
to guarantee full compatibility between Dulcinea Control System and your SPM system.
Inertial Box
Most Ultra High Vacuum SPM systems base
their coarse tip-sample motion in an inertial
slip-stick mechanism: the application of a soft
voltage ramp, followed by an immediate return
to the initial voltage generates an effective and
repetitive tip-sample movement that is needed
for the tip-sample approach or other large movements
(in the range of tens of mm) inside the
UHV chamber.
We have designed and developed a Universal
Inertial Box that, with 7 BNC ouputs, allows interfacing
easily the Dulcinea controller with any
UHV SPM system controlling up to 7 different
movements.
Nanotec universal inertial box
3rd party interfaces
Nanotec interfaces for Veeco
In the same way we have adapted WSxM to
read file formats for any SPM in the market, we
have also developed interfaces for being able
to use WSxM to control any SPM head that we
have been requested to. Our electronics department
is always happy to receive new requests
to connect Dulcinea to any home-made
or third-party SPM head.
Nanotec Interface for Omicron
28 29

eference list
(bibliography)
GSI
“DNA molecules resolved by electrical double layer force spectroscopy
Imaging” J. Sotres et al. Appl. Phys. Lett. 93, 103903 (2008)
Lithography
“WSXM: A software for scanning probe microscopy and a tool
for nanotechnology”, I. Horcas et al., Rev. Sci. Instr. 78, 013705 (2007)
“Site-controlled lateral arrangements of InAs quantum dots grown on GaAs(001) patterned
substrates by atomic force microscopy local oxidation nanolithography” J Martín-Sánchez
et al, Nanotechnology 20 (2009) 125302
“Single Photon Emission from Site-Controlled InAs Quantum Dots Grown on
GaAs(001) Patterned Substrates”, J. Martín-Sánchez et al., ACS Nano, vol. 3, no 6
1513–1517 (2009)
Nanomanipulation
“Atom inlays performed at room temperature using atomic force microscopy”, Y. Sugimoto
et al., Nature Materials, 4, (February 2005).
Frequency Modulation
“Enhancing dynamic scanning force microscopy in air: as close as possible”, E. Palacios-Lidón
et al., Nanotechnology 20 (2009) 085707
KPM
“Surface potential domains on lamellar P3OT structures”, B. Pérez-García et al., Nanotechnology
19 (2008) 065709
“Quantitative electrostatic force microscopy on heterogeneous nanoscale samples”,
E. Palacios-Lidón et al., Appl. Phys. Lett. 87, 154106 (2005)
“Probing Local Electronic Transport at the Organic Single-Crystal/Dielectric Interface”. Yi Luo et al.
Adv. Mater. 0000,00, 1-7 (2007)
Drift correction
"Surface diffusion of Pb single adatoms on the Si (111)-( 3 x 3 )R30º -Pb system". I. Brihuega,
M. M. Ugeda, and J. M. Gómez-Rodríguez. Physical Review B 76, 035422 2007.
"Direct Observation of a (3 x 3) Phase in Alpha-Pb/Ge (111) at 10 K". I. Brihuega, O. Custance, M.
M. Ugeda, N. Oyabu, S. Morita, and J. M. Gómez-Rodríguez, Physical Review Letters 95, 206102
(2005)
Conductivity
“Tuning the conductance of single-walled carbon nanotubes by ion irradiation in the
Anderson localization regime” C. Gómez-Navarro et al., nature materials, 4, (July 2005)
“Scanning force microscopy three-dimensional modes applied to conductivity measurements through
linear-chain organic SAMs”, C. Munuera et al., Nanotechnology 18 (2007) 125505
VF-MFM
“Variable-field magnetic force microscopy”, M. Jaafar et al., Ultramicroscopy 109 (2009) 693–699
“Field induced vortex dynamics in magnetic Ni nanotriangles”, M. Jaafar et al., Nanotechnology 19
(2008) 285717
“Remanence of Ni nanowire arrays: Influence of size and labyrinth magnetic structure” J. Escrig et
al., Phys. Rev. B 75, 184429 (2007)
K estimation
“Frequency response of cantilever beams immersed in viscous fluids with applications to the atomic
force microscope”, J. E. Sader, J. Appl. Phys. 84 64 (1998).
30 31

Acknowledgements
Nanotec wants to thank all those researchers who collaborate with us in the development of our AFM,
giving us feedback and reasons for new challenges. In particular, for the developments appearing in
these pages we acknowledge to the following research groups and individual researchers: J. Abad
(Murcia University), M. Abe (Osaka University), A. Asenjo (ICMM-CSIC), A. Baró (ICMM-CSIC),
I. Brihuega (UAM), F. Briones (IMM-CNM-CSIC), C. Carrasco (UAM), I. Casuso (University of
Barcelona), V. Chab (Inst. of Physics AS CR), F. Chandezon (CEA Grenoble), O. Cheshnovsky (Tel
Aviv University), J. Colchero (Murcia University), O. Custance (NIMS), P. de Pablo (UAM), I. Díez-
Pérez (University of Barcelona), L. Fumagalli (University of Barcelona), F. Fuso (Pisa University), J.
M. García ((IMM-CNM-CSIC), R. García (IMM-CNM-CSIC), J. Gómez-Herrero (UAM), C. Gómez-
Navarro (UAM), M. Gómez-Rodriguez (UAM), G. Gomila (University of Barcelona), L. González (IMM-
CNM-CSIC), Y. González (IMM-CNM-CSIC), P. Gorostiza (University of Barcelona), G. Gramse
(University of Barcelona), B. Grevin (CEA Grenoble), M. Hernando (UAM), M. Jaafar (ICMM-CSIC),
A. Kuhnle (Osnabrück University), M. Luna (IMM-CNM-CSIC), J. A. Martín Gago (ICMM-CSIC), J.
Martín-Sánchez (IMM-CNM-CSIC), D. Martínez (UAM), J. Méndez (ICMM-CSIC), F. Moreno (CBM-
CSIC), M. Moreno-Ugeda (UAM), S. Morita (Osaka University), C. Munuera (ICMAB-CSIC), C. Ocal
(ICMAB-CSIC), E. Palacios-Lidón (University of Murcia), J. I. Pascual (Freie Universität Berlin), B.
Pérez-García (Murcia Univ.), D. Porath (Hebrew University Jerusalem), E. Prieto (CEM), M. Puig
(University of Barcelona), A. Raman (Purdue University), M. Reichling (Osnabrück University), R.
Reifenberger (Purdue University), C. Rogero (INTA), A. San Paulo (IMB-CNM-CSIC), F. Sanz (University
of Barcelona), I. Schaap (Vrije Universiteit Amsterdam), J. Soler (UAM), J. Sotres (ICMM-
CSIC), Y. Sugimoto (Osaka University), P. Szabo (CLTP-SAS), F. Terán (Gaiker), J. L. Toca (CIC
biomaGUNE) and all the people working in their groups.
other
partners
32

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