On the Surface- and Material Science (SMS) branch there are two focal points; the first one is inside the permanent UHV end station and the second one (2.5 m downstream) is on open port, which can be used for user-provided end stations.

The permanent UHV end station on the SMS branch is dedicated to photoelectron and x-ray absorption spectroscopy studies on surfaces and thin films. It comprises four chambers: an analysis chamber with detectors, two preparation chambers with sample transfer and treatment facilities, and a fast entry chamber with a sample garage. Main characteristics of this system are described below.

 

A 3D model of this system is available to the potential users on request.

 

Analysis chamber

Base pressure1⋅10-10mbar
Sample manipulation4-axis LHe/LN2 manipulator (VG Omniax):
3 motorized translations x,y = ±12.5 mm, z = 600 mm and 1 motorized rotation: 360° polar angle
Omicron flag-type sample holders
SourceLPU 54.4 mm
Beam size at sample Defocused (h x v): up to 2 x 1 mm
Focused (h x v): 65 x 10 μm; further reduction in size
is possible with baffles (at the cost of flux)
CoolingOpen-cycle He-flow cryostat (a custom-made variant of Janis ST-400)
LN2: 90 K on sample
LHe: ~21 K on sample (Cu-manipulator head)
LHe: ~35 K on sample (Mo-manipulator head)
On-sample K-type thermocouple sensor for both heads (transferrable with the sample plate)
If necessary, a Si-diode sensor may be mounted close to the sample area for more precise low-T measurements (at the cost of reduced heating capabilities)
Magnetic shieldingμ-metal liner
CharacterizationScienta SES-2002 spectrometer with MCP/CCD detector (is planned be replaced or upgraded in 2019)
NEXAFS MCP detector for PEY and TEY experiments
NEXAFS in TEY mode via sample drain current
NEXAFS in partial FY mode with Sirius 70 mm2 active area SDD (Rayspec)

 

Main preparation chamber (for relatively clean sample preparation procedures)

Base pressure1⋅10-10mbar
Sample manipulation Same main manipulator as for the analysis chamber (VG Omniax); magnetic transfer arms (FerroVac)
Sputter gunYes (Physical electronics)
HeatingTwo types of manipulator heads are available depending on the temperature range of an experiment:
1. Mo-based manipulator head for better heating. Radiative heating by filament (up to 800 C), e-beam heating (up to 1200 °C, but only very shortly) and direct current heating (up to 1400 °C)
2. Cu-based manipulator head for better cooling. Up to 200 °C with a button-heater.
On-sample K-type thermocouple sensor for both heads.

CoolingSame as for the analysis chamber
CharacterizationLEED (Omicron 3-grid SPECTALEED)
RGA (MKS Microvision 2)
Deposition3 quick install deposition source ports CF 40 (behind a gate valve)
Additional CF40 ports if necessary
Quartz thickness monitor on request
DosingGas-sending system with 4 separate gas lines and 1 liquid vapor line connected to leak valves on the chamber (under construction, please ask in advance if gas usage is planned)
OtherSample garage for storing up to 6 samples in UHV.
On demand: wobble sticks, vacuum files, vacuum screwdrivers, etc Possibility to attach vacuum suitcase (to be requested in advance).

 

Secondary preparation chamber (for molecular film depositions and other less clean preparations)

Base pressure1⋅10-10mbar
Sample manipulation4-axis LN2 manipulator (Prevac, customized):
3 translations: x,y = ±12.5 mm, z = 150 mm
1 rotation: -180°…+150° polar rotation
Only z and rotation are motorized

Magnetic transfer arms (FerroVac)
Sputter gunYes (Thermo VG Scientific)
HeatingMo-based manipulator head, on-sample K-type thermocouple sensor
Radiative heating by filament (up to 800 °C)
Electron beam heating (up to 1200 °C)
Direct current heating (up to 1400 °C)

Coolingno
Deposition4 CF40 ports for user supplied evaporation sources, some gated with valves for quick equipment installation
Thickness monitor on request
DosingGas lines / Leak valves (under construction)

 

Fast entry chamber

Base pressure5⋅10-8mbar
Sample storageCapacity: 6 sample plates

 

Analyzer

TypeScienta SES-2002 (has to be replaced or upgraded in 2019)

Energy resolution< 2 meV FWHM at 2 eV pass energy and 20 eV kinetic energy
Angular resolution< 0.1 degree
Detector40 mm MCP/CCD
SlitsIn mm: 0.2s, 1.5s, 2.5s, 4.0s with slit length of 30 mm
In mm: 0.2c, 0.3c, 0.5c, 0.8c with slit length of 25 mm
(s = straight, c = curved)
ModesTransmission
Angular ±3.5°,±7°