Research in a wide range of disciplines – materials science, nano-science, heterogeneous catalysis, corrosion science, polymer science to name but a few – is in strong need of improved surface imaging techniques with structural, chemical, electronic, and magnetic contrasts at spatial resolutions in the nanometer range. Spectroscopic PhotoElectron and Low Energy Electron Microscope (SPELEEM) is unique in that it provides easy access to all of these contrast mechanisms at resolutions in the nanometer range in a single instrument. One of recent and the most important developments concerning this instrument is the upgrade to a microscope with an aberration corrector, which improves the spatial resolution of the microscope by an order of magnitude while increasing the transmission by a similar factor. SPELEEM also has the advantage of having a large dynamic range of view of up to ~100 micrometres thereby facilitating easy access to the structure of not only the nanometer but the micrometer scale as well. Finally, as the detection in SPELEEM is done at video-rates, monitoring of real-time dynamical processes is possible.

Endstations or Setup

MAXPEEM endstation

Description
MAXPEEM endstation:
It comprises two main chambers:
1. The preparation chamber, dedicated to sample preparation and treatment facilities.
2. The main chamber, dedicated to the analysis of the sample surface.
The main chamber hosts the aberration-corrected SPELEEM microscope (Elmitec GmbH)
Base Pressure
4 * 10-11 [mbar]
Endstation Operative
Yes

Sample

Sample Type
Other: Conductive surfaces and thin films.
Required Sample Size
X = 10 [mm], Y = 10 [mm], Z = 2.5 [mm]

Manipulator or Sample stage

Description
Main chamber manipulator:
4-axis manipulator with 3 translations (x,y,z) and 1 tilt adjustment (±2°)
Degrees Of Freedom
4
Translator Stages
3
Cradles
1
Range Of Movement
X = 5 [mm], Y = 5 [mm]
Description
Preparation chamber manipulator:
4-axis manipulator with 3 translations (x,y,z) and 1 polar rotation.
Only z is motorized.
Degrees Of Freedom
4
Translator Stages
3
Cradles
1

Sample Environment

Description
Main chamber:
Radiative heating (up to 400 °C) and e-beam heating (up to 1500 °C) are available.
The temperature is measured with a C-type thermocouple (W5%Re/W26%Re) spot-welded on the Mo ring under the sample.
An infrared pyrometer is also available.
LN2 sample cooling is available.
An Hg-arc UV-light source (LOT-QuantumDesign GmbH) is available.
Five samples can be stored in the chamber.
Pressure (min)
4 * 10-11 [mbar]
Temperature
80 - 1773 [K]
Description
Preparation chamber:
Sputter gun (Varian, 981-2043) and metal evaporator (Focus GmbH, EFM 3).
Radiative heating (up to 400 °C) and e-beam heating (up to 1500 °C).
The temperature is measured with a C-type thermocouple (W5%Re/W26%Re) spot-welded on the Mo ring under the sample.
An infrared pyrometer is also available.
Gas dosing through leak valve is available.
Loading of one sample/time is possible through a fast entry chamber directly connected to the preparation chamber.
Pressure (min)
2 * 10-10 [mbar]

Sample Holders

Type
Sample holder
Description
The sample is fixed into the sample holder with a Mo cap after gentle tightening of four symmetrically placed M2 screws.
The sample can be heated to 400 °C (radiative heating) with a filament built in the sample holder, or be heated to even higher temperatures (1300-1500 °C) by e-beam bombardment.
For a rough temperature measurement, there is a type-C thermocouple (W5%Re/W26%Re) spot-welded on the Mo ring under the sample. For a more accurate measurement, an infrared pyrometer is available.

The size of the sample should generally not be less than 5×5 mm2 and not more than 10×10 mm2 (square) or Φ14 mm (disc). The maximum thickness is 2.5 mm.
contacts
Alexei Zakharov
Techniques
Absorption
  • NEXAFS
  • XMCD
Imaging
  • Photoemission EM
  • X-ray microscopy
Photoelectron emission
  • Angular Resolved PES
  • XPS
control/Data analysis
Control Software Type
  • Tango, U-View
Data Output Type
  • standard
Data Output Format
  • standard