General information

SR beam spot size100 µm x 100 µm
Pressure range for XPS measurementsUHV to 20 mbar
AnalyserSPECS Phoibos 150 NAP
Energy range30 to 1500 eV

The SPECIES APXPS endstation is designed for ambient-pressure XPS measurements using dedicated cells. The endstation is equipped with UHV manipulator to facilitate normal measurements in UHV conditions with sample heating and some sample preparation methods. Dedicated ambient pressure cells enable measurements to be carried out at higher gas pressures. Below we describe the endstation in detail.

X-ray transmission through different windows

Approximate flux inside the AP cell (using Al window)

Analysis chamber

Base pressure5e-10 mbar
Sample manipulationX, Y, Z, rot (UHV manipulator
X, Y, Z (AP cells)
X-ray sourcesEPU61, 1.5 GeV ring and
SPECS XR50 with Mg and Al anodes, 250 W power (not monochromatized and unfocused)
Sample storageGarage with 3 sample slots

Ambient Pressure XPS

Max pressure20 mbar
Max temperatureStandard cell: Up to ~600 C with resistive heating (Graphite heater disk under the sample). Maximum temperature is environment (gas) dependent

ALD cell: Up to ~400 C with resistive heating (button heater with Pt filament)
Min temperatureStandard cell: about 0 C with LN2 cooling. Ask beamline staff for more info.
SR incidence angle57 deg with respect to electron analyser
SR window materialAl, 200 nm (default)
Si3N4, 200 nm (upon request)
Zr, 200 nm (upon request)
Electron detection angleNormal to surface
Analyser apertures (with AP cells)0.3 mm (default)
0.5 mm
1.0 mm
Mass specsGas inlet/outlet: Pfeiffer QMS 250 M2, PrismaPro up to 200 amu range

Prelense: VACOM NOVION TOFMS up to 200 amu
Gas dosingUsing MFCs or leak-valves.
Standard cell:
Current status: Up to two independent (hazardous) gases
Under construction/validation: Two gas mixing panels for a total of 8 gases.

ALD cell:
Two precursors with their independent gas lines. Possibility for additional gases upon request.
Standard cellAvailable for users
Sulphur cellCell under commissioning/construction. Gas system under construction
ALD cell
ALD cellAvailable for users.

UHV XPS

Max pressure1e-5 mbar (backfilling mode)
Min pressure2e-10 mbar
Max temperature Up to ~1000 C with e-beam heating (PID control)
SR incidence angle55 deg with respect to analyzer
Electron emission angleVariable

Analyser

TypeSPECS Phoibos 150 NAP with differentially pumped lens system
Energy resolution< 10 meV, depending on applied settings
Kinetic energy range0 to 3.5 keV
DetectorDelay line detector (Surface Concept).
ModesTransmission (medium and small area), angular
SoftwareSpecsLab Prodigy

Preparation chamber

Base pressure2e-10 mbar
UHV manipulatorX, Y, Z and polar rotation
HeatingUp to ~1000 C with e-beam heating (PID or manual control)
CoolingAir cooling of sample stage
Sputter gunSPECS Ar Sputter gun
LEEDSPECS ErLEED
Evaporation sourceFocus EFM 3T triple cell evaporator
GasesPossible to dose up to 5e-5 mbar using a leak-valve
ElectrosprayAvailable upon special request
Available ports for user equipmentPort size DN40CF with a manual gate valve (no need of venting preparation chamber for installation)

Load-lock

Base pressure2e-8 mbar
Sample holderFlag style (see below)
Sample sizeApproximately 8 mm x 8 mm (see image below)
Transfer time30 min (from air)
Vacuum suitcasePortable vacuum suitcase (e.g. from STM lab) can be installed in place of the transfer arm.
Available ports (atmospheric suitcase)Portable atmospheric suitcase with 8 sample slots.
It can be taken to chemistry lab glove box and filled with inert gas.

SPECIES uses flag style samples with a modified thermocouple design. Users can request to have sample holders shipped to them in advance. Sample holder is compatible with the design at HIPPIE beamline (Samples from HIPPIE can be taken to Species, but not vice versa).

The sample plates contain an on-board K-type thermocouple which allows for sample temperature measurements. The thermocouple junction can be spotwelded on the plate, or anywhere else depending upon user needs.

Additional equipment

List of additional equipment available at the SPECIES-APXPS endstation. Please ask the beamline staff for further information

  • Solar simulator (Assahi Spectra HAL-320W) with a customized light guide. Typically attached to a CF40 flange on the endstation so that light can be used in either UHV manipulator or inside the AP cell. Use of solar simulator requires that the X-ray anode is removed.
  • Xenon flash lamp (Hamamatsu  L6605, 60W). Pulsed lamp with variable repetition rate (10-100 Hz) and variable intensity. Typically attached directly to a fused silica CF40 flange on the endstation. Use of the UV lamp requires that the X-ray anode is removed.