• 20nmLateralResolution

• EasytoOperate

• Real-TimeImaging

• SurfaceSensitiveMicroscopy

• ChemicalMapping

• LocalSpectroscopy

• CompatiblewithMULTIPROBEUHVSystems

FOCUS PEEMPhoto Emission Electron Microscope

The Bolt-On PEEMAn Ease of Operation Concept

1 mm

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Standard sample plate for PEEM.

1 µm

Platinum wires, 8 nm thick, 50 nm wide (smallest dimen-sion) on a 20 nm thick Titanium oxide film on 100 nm Silicon oxide. The sample shows an array of 17 wires starting with contact areas of approximately 40 µm which contact a wire line, each wire has a width of 50 nm. A small FoV (field of view) of 9 µm shows that the 50 nm wires and contacting area can be clearly resolved.

Similar to SEM: navigation along large structures. Platinum wire array on TiOx A) 590 µm FoV (white circles)B) 94 µm FoV.

Photoemission Electron Microscopy (PEEM) is an extremely powerful ima-ging technique, whose versatility for topographical, chemical and magnetic contrast imaging at high resolution has been demonstrated in many labo-ratory and synchrotron applications.

Important contributions to characterisation of magnetic devices, plasmon research, surface chemistry and high lateral resolution chemical analysis in combination with synchrotron radia-tion, investigation of time resolved processes and k-Space imaging are only a few examples of active PEEM based research.

In contrast to a Scanning Electron Microscope (SEM), PEEM directly images surface areas emitting photoelectrons in real-time, without scanning. Electron emission from surfaces can be caused in various ways - by photon irra-diation excitation, thermally, via electron/ion bombardment or by field emission.

Over the years the FOCUS PEEM has been con-tinually improved in performance and usability. The PEEM together with the dedicated high stability integrated sample stage (IS) and var-ious available energy filters follows a modular concept easy to upgrade. In addition software assisted operation ensures time efficient and secure PEEM operation even on challenging samples. With more than 50 units in the mar-ket the FOCUS IS-PEEM is a powerful surface analysis tool featuring:

• Convenient software assistance• Easy integration into UHV Systems• Uncompromised stability with IS-Stage• k-space imaging • Key strengths in spectroscopy: - Time-of-flight analysis - High-pass imaging energy filter - Micro-analyzer - Aberration compensated band pass filter

An Ease of Operation Concept

10 µm

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Integral sample stage

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Micro-analyzer Time-of-flight energy filterImaging energy filter Imaging detectorFOCUS PEEM Features

The FOCUS PEEM BA is the basic version of the PEEM instrument series. It is a bolt-on instrument which can be easily integrated in vacuum chambers. It is the heart of all extended PEEM instruments.

For high performance PEEM operation a rigid and com-patible sample manipulator is required in order to avoid the influence of mechanical vibrations.

The FOCUS PEEM features a three-lens, fully electrostat-ic electron column consi-sting of a tetrode objective lens - an immersion lens in which the sample is part of the lens- and a distortion-free double projective lens.

Combined with the adju-stable Contrast Aperture and the Stigmator/Deflector module, the electron optics is capable of a resolution below 20 nm.

The Modular Concept

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FOCUS IS-PEEM with IEF and cryo stage.

The integral sample stage of the IS-PEEM guarantees ulti-mate stability for optimal resolution avoiding any possible relative movement of sample and objective by mechanical integration of the sample into the objective. This is of particular importance for applications with long acquisition times, which can be obtained without compromising the resolution. The piezo-electrically driven IS-stage provides precise positioning of the sample within an area of 8 x 8 mm with an accuracy of 100 nm. The IS-stage may be retrofitted to the FOCUS PEEM BA. The sample plates (molybdenum or stainless steel) for the IS-PEEM are compatible with Omicron’s range of instru-ments for multi-technique surface science and UHV SPM. A dedicated bolt-on PEEM chamber allows for easy combina-tion with other surface science applications.

Position ReadoutThe optional position readout allows the user to navigate on their samples, and reposition automatical-ly on any interesting feature. In addition the position readout also allows for automated large area mapping.

Variable Temperature The IS-stage can be equipped with an electron bombardment sample heating facility (sam-ple at ground potential) for temperatures up to 2300 K, allowing the imaging of thermally induced phase transitions or even thermally emitted electrons during heating. Optionally, the IS-stage may be fitted with sample cooling down to about 100 K. In addition a dedicated low temperature sample stage for operation down to 25 K is available on request.

Iris Aperture The optional variable iris aperture enables reduction of the PEEM‘s field of view down to a well defined micro-spot as small as 1 μm in diameter. The iris aperture is essential for micro-spot analysis. The aperture size is con-tinuously adjustable via a rotary feedthrough. Precise positioning of the micro-spot for local analysis, e.g. using X-ray absorption spec-troscopy (μ-XPS/μ-UPS), is accomplished by either the stigmator/deflector or the integrated sample stage of the IS-PEEM. The iris aperture is also required for k-space imaging.

Energy FilteringThe FOCUS PEEM is especially well-suited for spectroscopic PEEM applications. Depending on the application it can be equipped with various

energy filters such as the Imaging High-Pass Energy Filter (IEF), Time-of-Flight (TOF) detec-tors or the aberration compensated band pass for highest transmission spectroscopic PEEM imaging. Various filter concepts will be dis-cussed on the following pages.

k-Space LensImaging of the angular distribution of the emit-ted electrons instead of the ‘real‘ image is pos-sible by switching from real space to k-space imaging. In the FOCUS PEEM, this is achieved with the optional transfer lens. Additionally the transfer lens allows for very large area imaging >1000 µm. In combination with the TOF, IEF or NanoESCA the instru-ment allows for k-space mapping with a very large acceptance angle of ± 90 degrees in the UPS regime. Moreover single shot Fermi surface imaging e.g. in combination with the HIS 13 VUV lab source or focussed high energy lasers becomes possible.

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Integral Image

-8.4 ns -7.2 ns -6.0 ns -4.8 ns

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-8.4 ns -7.2 ns -6.0 ns -4.8 ns

-3.6 ns -2.4 ns -1.2 ns

-8.4 ns -7.2 ns -6.0 ns -4.8 ns

-3.6 ns -2.4 ns -1.2 ns

(A) Integral of a time (energy) filtered image stack of Ag microstructures on a Si sub-strate and (B) local TOF spectra, taken with a 400 nm pulsed diode laser (60 psec/ 40 MHz) excitation. Note that the intensity in the nanosized ‘hot spot’ is enhanced by a factor of 200 and the energy onset of the electrons from ‘hot spot’ area is about 0.6 eV lower than that from the smooth area.

The Time-of-Flight (TOF) imaging energy filter is ideally suited for energy filtered low intensity appli-cations with electrons in the low kinetic energy range.

Together with a time sensitive imaging Delay Line Detector (2D DLD), a dedicated drift tube and a pulsed light source, the TOF PEEM offers a unique detection system. The detector allows true single electron counting with massive parallel detection and excel-lent signal to noise ratio. In addition to stan-dard energy filtered TOF PEEM experiments the detector also allows for time dependent studies with an overall time resolution of < 250 ps.

Lower drift energies inside the drift tube allow higher energy resolution. The special design of the FOCUS PEEM allows for opera-tion at extremely low drift energies (10 eV) while maintaining the lateral resolution of the instrument. The TOF PEEM has achieved an energy resolution of down to 50 meV.

A prerequisite for any kind of TOF experiment is a pulsed light source such as pulsed lasers or synchrotrons. The TOF detector may be retrofitted to existing FOCUS (IS-)PEEMs.

B

Time-of-Flight Energy Filter

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-8.4 ns -7.2 ns -6.0 ns -4.8 ns

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7 Time (Energy) filtered images with a time separation of 1.2 ns; electrons excited at the sample surface are separated by the TOF PEEM in time. Electrons with high kinetic energy will hit the detector earlier than electrons with low kinetic energy. Therefore each individual time slice corresponds to different electron energies.

FOCUS PEEM with TOF detector. The TOF PEEM consists of an FOCUS IS-PEEM together with a long drift tube and a 2D delay line detector (DLD) placed on a linear retraction mechanism.

Operational modes: The TOF PEEM features fast switching from standard (straight through) PEEM Mode to TOF PEEM operati-on by using a linear retraction mechanism: (A) non filtered Standard PEEM operation, (B) TOF operation. While the electrons are separated in energy by passing a dedicated low energy drift tube, a time sensitive detector records the time structure of the incident electrons with respect to a trigger signal generated by the photon excitation source (e.g. laser, synchrotron etc.). A two wire array, the 2D delay line detector (DLD) records the time-of-flight t0 (C). In addition the travel time of the signal through the wire in x (tx1, tx2) and y directions is recorded to locate the position of the incident electron on the detector (D).

t0

tx1

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Time of Flight Filter

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tfirDTube

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Spectral Unmixing is an algorithm integrated in the PEEM imaging software that per-forms a least error fit of up to four prototype spectra (here two: green and red) to each pixel in the spectral image series (see below). It identifies the correlation of the image with the ‘finger print‘ of the related spectra. The weights of each prototype spectrum are displayed in separate images. The right hand image represents the mixed weights of the two prototype spectra shown above colored in green and red within the image.

Integral Image Spectral unmixed

0.34 eV 0.45 eV 0.56 eV

0.98 eV

0.66 eV

0.77 eV 0.87 eV

0.34 eV 0.45 eV 0.56 eV

0.98 eV

0.66 eV

0.77 eV 0.87 eV

0.34 eV 0.45 eV 0.56 eV

0.98 eV

0.66 eV

0.77 eV 0.87 eV

The incorporation of energy filtering into the FOCUS PEEM yields improved performance and opens up new ap-plication possibilities. The retarding imaging energy filter (IEF) acts as a high pass filter for the full image.

Setting the energy filter to a specific elec-tron energy facilitates element specific mapping with increased contrast. The IEF is a dedicated energy filter for all applications with good photoelectron yield.The IEF effectively reduces the chromatic aberration, i.e. the energy spread of the electrons contributing to the formation of the image. This is of particular importance for chemical and magnetic imaging in syn-chrotron applications, where the achievable resolution is reduced due to the ‘unfocused‘ contribution of high energy electrons.

The IEF can also be used for micro spec-troscopy analysis. XPS and AES spectra up to a kinetic energy of 1600 eV and with energy resolution well below 100 meV can be obtained in areas smaller than 1 μm. Using laboratory excitation sources (threshold photoemission microscopy), ima-ging at specific work functions with energy filtering yields a strongly enhanced contrast.

The raw data are collected as images at a certain cut-off energy with a CCD camera. The spectra are extracted from the images, also allow-ing integration over selected areas within the image. The IEF may be retrofitted to existing FOCUS (IS-)PEEMs.

Imaging High-Pass Energy Filter

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0.34 eV 0.45 eV 0.56 eV

0.98 eV

0.66 eV

0.77 eV 0.87 eV

0.34 eV 0.45 eV 0.56 eV

0.98 eV

0.66 eV

0.77 eV 0.87 eV

0.34 eV 0.45 eV 0.56 eV

0.98 eV

0.66 eV

0.77 eV 0.87 eV

Energy filtered image series with an increment of 110 meV per image. Sample: Polycristalline Copper.Excitation: 4.9 eV (Hg arc lamp).

The Imaging Energy Filter (IEF) is fitted at the exit of the IS PEEM (A). The IEF PEEM features two operational modes: the standard non-filtered PEEM mode and the filter mode (B). The IEF operates as a high pass filter. The potential difference between a micro-grid and the sample is tuned to select the cut off energy. For kinetic energies of incident electrons higher than the potential E0 electrons pass the grid and will be recorded by the data acquisition system (middle). In case the kinetic energy is lower than E0 the electrons will be repelled at the micro grid (bottom).

Entrance Lens

Octopole Stigmator

Contrast Aperture

Sample

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Objective Lens E = E

0

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Micro Analyser

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Slits

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Channeltron Detector

hν

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PEEM

hν

Imaging Energy

Analyser

Screen

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MCPExit Lens

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Transfer Lens System

Entrance Lenses

Octopole Stigmator

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Objective Lens Slits

PEEM

CCD Camera

hν

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ScreenEntrance Lens

Slits

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Entrance Lens

Octopole Stigmator

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Objective Lens

Double Micro Grid (E

0)

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Micro Analyser

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Slits

Contrast Aperture

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PEEM

Channeltron Detector

hν

CCD Camera

Octopole Stigmator

Projection Lenses

PEEM

hν

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Analyser

Screen

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System

Transfer Lens System

Entrance Lenses

Octopole Stigmator

Contrast Aperture

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Projection Lenses

Objective Lens Slits

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CCD Camera

hν

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Time of Flight Filter

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2ndStigmator

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Projection Lenses

The micro-analyser is fitted at the exit of the IS PEEM (top). The PEEM with micro-analyser features two operational modes: the standard non-filtered PEEM mode and the filter mode. The straight through non filtered PEEM mode allows standard PEEM operation and localisation of areas of interest for local spectrum acquisition (middle). Once the area of interest is defined, all photo electrons can be deflected into the micro-analyser by activating the ‘entrance lens‘ for local small area spectroscopy (bottom).

Reference: 1) G. Takyo, S. Kono, T. Goto, H. Sasaoka, and K. Nishimura / Jpn. J. Appl. Phys., Vol. 47, No. 4 (2008)

Large area mapping & spectroscopy with micro-analyser: CVD Diamond Film & Field Emission Origin of Field Emission from a Nano-Diamond/Carbon Electron Emitter: Mosaic of 230 PEEM images of a chemical vapor depo-sition (CVD) diamond film with a field of view of about 55 µm.1)

Energy distribution curves of field-emitted electrons of a field emission spot from a ~5 µm area.1)

The FOCUS PEEM micro-analyser combines real- time surface microscopy with local chemical analysis using microspot electron spec-troscopy (kinetic energy up to 1600 eV) at an energy resolution down to 80 meV and below.

Laboratory and synchrotron sources (soft-XPS, UPS, AES) may be used. The PEEM acts as a high performance entrance lens with variable magnifi-cation for the 50 mm hemis-pherical analyser.

The variable lateral resoluti-on can be selected down to 1 μm spot size with the Iris aperture. In contrast to the imaging energy filter, the micro-analyser features dedi-cated small spot spectroscopy performance with high energy resolution and discrete pass energies between 1 eV and 80 eV. The micro-analyser may be retrofitted to existing FOCUS (IS-)PEEMs.

PEEM with Micro-Analyser

8811

Entrance Lens

Octopole Stigmator

Contrast Aperture

Sample

Projection Lenses

Objective Lens

Double Micro Grid (E

0)

PEEM

PEEM

hν

hν ScreenMCP

Micro Analyser

ScreenEntrance Lens

Slits

Contrast Aperture

Sample

IrisAperture MCP

2ndStigmator

Objective Lens

PEEM

Channeltron Detector

hν

CCD Camera

Octopole Stigmator

Projection Lenses

PEEM

hν

Imaging Energy

Analyser

Screen

Imaging Energy Analyser

MCPExit Lens

System

Transfer Lens System

Entrance Lenses

Octopole Stigmator

Contrast Aperture

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Projection Lenses

Objective Lens Slits

PEEM

CCD Camera

hν

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hν

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ScreenEntrance Lens

Slits

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Sample

IrisAperture MCP

2ndStigmator

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PEEM

hν Octopole Stigmator

Projection Lenses

Synchrotron ESRF, beamline ID08Chemical maps at Au 4f, Si 2p, Ti 2p, C 1s and O 1s core level energies. Sample: ElectrograftedpMAN on Au/SiO2. FoV: 127 µm.

Si 2p O 1s(2)

Ti 2p O 1s(1)

Au 4f C 1s

20 µm

NanoESCA*: see also www.omicron.de/nanoesca and our separate NanoESCA brochure

The NanoESCA is an imaging analyser derived from an electrostatic photoemission electron microscope (PEEM) column, combined with the aberration compensated double hemispherical analyser. Three operating modes are available: • direct non-energy-filtered PEEM, • energy filtered imaging, • small spot, area selected spectroscopy.

NanoESCA* features ultimate spectroscopic performance for PEEM imaging in the UPS and XPS regimes.

The NanoESCA consists of a PEEM and an imaging energy analyser. The dedi-cated aberration compensated imaging energy band pass filter allows for ulti-mate spectroscopic PEEM performance. Highest transmission and optimum energy resolution are key features of the NanoESCA. The complete image is transmitted through the double-pass analyser. Aberrations introduced by the first hemispherical analyser are fully compensated to the 3rd order by the second hemispherical analyser - a patented arrangement allowing for ex-cellent laterally-resolved chemical state photoelectron spectroscopy results with optimum signal to noise ratio. Imaging XPS and UPS features a kinetic energy range from 0 eV to 1600 eV at < 200 meV energy resolution (imaging mode: achieved 110 meV). In addition a (optional) small spot spectroscopy mode is available. The small spot spectro- scopy mode provides precise quantification as well as the detection of localised contam-inants. In addition the non-filtered PEEM mode allows for high resolution imaging: 30 nm achieved. A dedicated monochroma-ted small spot laboratory Al Kα X-ray source is optionally available. The unique combina-tion of the high flux density X-ray source and NanoESCA´s excellent transmission allows for unsurpassed XPS core level imaging with achieved lateral resolution of below 500 nm in convenient laboratory conditions. The opti-onal transfer lens allows for µ-ARPES with full control over the analysed area by real space PEEM imaging (momentum microscope).

Imaging Double-Pass Energy Analyser

12

The FOCUS IS-PEEM strictly follows the flexible ‘bolt-on‘ concept - a flange mounted instrument without the need for a dedicated PEEM UHV system.

With the integrated sample stage (IS) directly attached to the lens system the FOCUS IS-PEEM allows for uncompromised mechanical stability when attached to a UHV system. It is compatible with Omicron sample transfer and other surface analysis instruments. The modularity of the FOCUS PEEM with the PEEM´s unique contrast mechanisms and high resolution fits perfectly with the wide range of modular Omicron solutions.

The bolt-on concept at a glance:• Flange mounted instrument• Simple integration into UHV systems • Integrated sample stage for minimum vibration• Integrated mu-metal shield• Easy to upgrade and maintain• Sample handling compatible with many other Omicron instruments

The PEEM Probe is a UHV system with a small food print tai-lored for the needs of daily PEEM work. It provides ports for various excitation sources, evapo-rators, a sputter cleaning source and sample heating.In addition the system is also designed to house a dedicated LHe cooled sample stage for PEEM operation below 30 K.

A perfect match: MULTIPROBE S housing the FOCUS IS-PEEM with IEF and the VT SPM.

The PEEM allows quantitative work function analysis while VT SPM provides atomic

resolution in all AFM and STM modes.

UHV system for MBE growth, PEEM and SPM work. Combination of a dedicated MBE growth system MULTIPROBE MBE housing various evaporators and RHEED with an FOCUS IS-PEEM and a VT SPM for in-situ characterisation of thin films.

Bolt-On Concept / System Integration

Together with the recently developed software ‘ProPEEM‘, the whole PEEM instrument becomes a very easy to operate surface analysis tool.

The quality of the results usually depends not only on the imaging and analytical properties of the PEEM column but also on the ease of operation and the user skill level. ProPEEM - based on extensive electron optical simula-tions - is an intuitive graphical user interface which provides convenient assistance to the operator. The user has direct control of the microscopes magnification which can be continuously adjusted from 1 : 20x to 1 : 7200x in a standard FOCUS PEEM. With recently implemen-ted features such as pre-focusing, automated detector intensity adaptation and a simpli-fied stigmation correction, ProPEEM allows for time efficient and convenient PEEM operation.

Screenshots of ‘ProPEEM‘ software. Left: User mode allows software assisted operation. The magnification can be selected by choosing the

field of view see (insert and example images on a test pattern). Right: aperture positioning screen.

The Intelli Control is a state-of-the-art fully computer controlled modular electronics. The front panel‘s

joystick allows for sample navigation in addition to all relevant parameters being monitored.

Ease of Operation PEEM Software

FoV: 40 μm FoV: 500 μm

13

14

Results

The PEEM with IEF is able to image the angular distribution of photo electrons. Shown here: Cu (111) excited with hν = 185 eV (WERA-beamline, ANKA, cooperation FOCUS/IFP). An image stack has been taken between EB = 8.5 eV and EB = -2.5 eV. The upper left image represents the kx/ky map at an energy EB = 2.1 eV. The right one reflects the cross section along an E/ky plane, the lower one shows an E/kx plane along the symmetry axis.

Orbital mapping of carbon-π*: Element specific imaging of a (100) diamond film reveals the presence of graphite. (40 x 50 µm2) 2)

Graphite

Molecules: para-sexiphenyl (6P)Nucleation and 3D growth of para-sexiphenyl nanostructures. Still image from PEEM growth video, after deposition of 6 ML, demonstrating the well ordered (203) oriented crystalline needles that form when 6P self-assembles on Cu(110)2 × 1–O at 140 °C (scale bar 10 μm). Needles: dark lines, wetting monolayer: bright areas between needles. 3)

Overview of the direction of the magnetic interlayer coupling in an FeNi–FeMn–Co single-crystalline trilayer on Cu(001). The Co thickness increases from left to right up to 8 ML. The thickness of the top FeNi layer is 6 ML. Layer-resolved magnetic domain images are acquired by XMCD-PEEM at the Fe and Co L3 absorption edges. a) Layer-resolved domain image of the top FeNi layer. b) Layer-resolved domain image of the bottom Co layer. 1)

Reference: 1) W. Kuch, L. I. Chelaru, F. Offi, J. Wang, M. Kotsugi and J. Kirschner / Nature Materials 1548 (2006) / 445003 (11pp)2) Ch. Ziethen et al. / J. Electr. Spectr. Relat. Phenom. 107 (2000) 261 · 3) A. J. Fleming, F. P. Netzer and M. G. Ramsey / J. Phys.: Condens. Matter 21 (2009) 445003 (11pp)

EB = 2.1 eV

M Γ

M‘

kx

ky

EF

E

EF

E

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15

Nanoscopic field control. a) The photoelectron distribution is displayed on a 1.13 µm x 1.13 µm square for p-polarised excitation of the star-shaped nanostructure with laser pulses at 790 nm. This distribution acts as a reference for the optimisation experiments with complex polarisation-modulated laser pulses. The color scale bar represents the photoemission yield in arbitrary units. The white arrow indicates the projected direction of incidence k (inci-dence angle 65°). The nanostructure positions are marked by white circles, and the regions of interest A and B by yellow squares. b) Adaptive optimisation of the A/B photoemission ratio leads to increased (red) and decreased (blue) contrast of electron yields from the upper and lower regions as compared to unshaped laser pulses recorded as a reference (black). For comparison, the range of contrast variation achieved by non-adaptive single-parameter scan-ning of the spectrally constant phase offset between the two pulse-shaper

polarisation components (green arrow) is smaller and does not provide the same degree of control. c) The experimental PEEM image after adaptive A/B maximisation using complex polarisation-shaped laser pulses shows predominant emission from the upper region. d) Photoemission after A/B minimisation is concentrated in the lower region. e, f, The optimal laser pulses as experimentally characterised display complex temporal electric-field evolu-tion for the maximisation (e) and minimisation (f) objectives. E1 and E2 indicate the two field components that are phase-modulated in the polarisation pulse shaper in the first and second LCD layer, respectively. They are at ±45° angles with respect to p-polarisation. The overall time window shown is 2 ps. g, h, The simulated two-photon photoemission pattern for the experimental pulse shapes in the cases of A/B maximisation g) and minimisation h) qualitatively confirm the experimentally demonstrated nano-optical field control. 4)

Organic Transistors: graphite and spin-coated P3HT.In order to optimize organic field effect transistors (OFETs), the charac-terisation of active-layer surfaces in terms of their roughness, chemical composition and distribution of surface potentials is important.Hg PEEM images of a source-drain structure made of graphite and spin-

coated P3HT. (A) Channel (dark area) and graphite electrodes, covered with P3HT. (B) Channel and graphite electrodes, partially covered with P3HT. The brighter areas represent zones without P3HT and lower surface potentials respectively. 5)

Reference: 4) M. Aeschlimann, M. Bauer, D. Bayer, T. Brixner, F. J. García de Abajo, W. Pfeiffer, M. Rohmer, C. Spindler & F. Steeb NATURE - Vol 446 - 15 March 20075) K. Müller, A. Goryachko, Y. Burkov, C. Schwiertz, M. Ratzke, J. Koeble, J. Reif, D. Schmeißer / e-Sci. Synthetic Metals. Vol. 146 (2004)

Specifications and descriptions contained in this brochure are subject to alteration without notice.

How to contact us

Headquarters: Omicron NanoTechnology GmbHLimburger Str. 75 65232 Taunusstein, GermanyTel. +49 (0) 61 28 / 987 - 0 Fax +49 (0) 61 28 / 987 - 185Web: www.omicron.dee-mail: info@omicron.de

We have agents and partners worldwide – please check our website to find your nearest contact.

Omicron NanoTechnology is part of the Oxford Instruments Group. For more information: www.oxford-instruments.comor just send us an e-mail: info.plc@oxinst.com

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BucharestRome St. CannatMadridDenver

PEEM

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Significant PEEM dimensions (in mm). Other configurations on request.

445

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Sample25°

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445

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Sample25°

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Specifications

Energy filtering

The FOCUS PEEM BA (with external manipulator):Same specifications as IS-PEEM, except for Lateral resolution: 80 nm

The FOCUS IS-PEEMLateral resolution: 40 nm Magnification: 1 : 20 – 1 : 7 200Field of view: 2.5 µm – 900 µm With k-Space lens: 2.5 µm - 1800 µm

Integrated sample stage: Motor: piezo / X and Y movement: ± 4.0 mmExtractor voltage range: 100 - 15 000 V

Software:• Auto Focus when magnification is changed• Simplified stigmation / deflection correction• Safety Guard for MCP • Aperture finding mode • Manual operation mode

Time-of-Flight • Type: Imaging TOF• Modes: filtered / non filtered / time resolved• Energy resolution: 100 meV• Full software support

Micro-Analyzer• Type: area integral • Modes: PEEM / spectroscopy• Energy resolution: 100 meV• Full software support

Imaging Energy Filter• Type: Imaging High Pass Filter• Modes: filtered / non filtered• Energy resolution: 100meV• Full software support

NanoESCA• Type: Imaging Band PassFor details please refer NanoESCA brochure

Camera:• Slow scan CCD camera• Peltier cooled slow scan CCD camera for low intensity applications

Options:• Absolute position read out • Iris field aperture • Extended extractor range 100- 30 000 V• Heating (PBN) temperature range: (room temp.) RT – 600 K• (E-Beam) temperature range: (room temp.) RT – 2 300 K High temperature: flash heating only• Cooling LN2 cooling with bath cryostat LHe flow cryostat (on request)• Excitation sources - Hg-lamp - D2-lamp - HIS 13 (He-Discharge lamp) see related brochure