UHV Surface Analysis Systems

System 1: UHV surface science / nanocluster catalysis system (SPECS GmbH).

This modular system consists of four UHV-chambers: a surface analysis chamber, a scanning tunneling microscopy chamber (variable temperature/pressure STM), a sample preparation chamber, a high pressure reaction cell, and a load lock chamber for quick sample transfer into UHV. The components that are present in each chambers are detailed below. Also available: an overview of the system, and a view of the chamber design.

Luis Ono, Abhilash Vincent, and Prof. Roldan

Sample preparation chamber:

4-pocket electron beam evaporator with flux monitor (Oxford Sci.) for in-situ metal growth.
Dual Knudsen-cell evaporator for in-situ growth of bimetallic alloys.
Quartz microbalance that monitors thickness during evaporation.
Hybrid atom/ion Plasma source (Oxford Sci.) for H₂, O₂, N₂ –› controlled production of ultrathin metal oxide films and removal of residual organics resulting from ex-situ nanoparticle synthesis.
Argon sputter gun for sample cleaning.
Mass spectrometer for rest gas analysis.

High pressure reaction chamber:

High pressure cell capable of exposing samples to pressures up to 20 bar while sealing the reaction volume from the surrounding UHV.
IR heater for heating samples up to 800°C.

Surface analysis chamber:

Hemispherical electron energy analyzer
Non-monochromatic (Al/Mg anodes) and monochromatic (Al/Ag anodes) X-ray sources for X-ray Photoelectron Spectroscopy (XPS) for characterization of chemical composition and electronic properties of nanomaterials.
Electron source (EQ 22/35, SPECS) for Auger Electron Spectroscopy (AES).
Ultraviolet Source for Ultraviolet Photoelectron Spectroscopy (UPS).
Mass spectrometer (HIDEN) for Temperature-Programmed Desorption (TPD).
Low Energy Electron Diffraction (LEED) for characterazing the crystalline structure of surfaces.
Gas manifold allowing four different gases and one vaporized liquid to be simultaneously injected into the analysis chamber.
Nanosecond YAG laser: 355 nm, 532 nm, 1064 nm (EKSPLA) for in-situ nanoparticle melting and re-shaping.
Argon sputter gun for sample cleaning.

Scanning Tunneling Microscopy chamber:

Variable Temperature/Pressure Scanning Tunneling microscope (Aarhus-SPECS)
Reaction cell with SPM head for AFM/STM, radiative heater, and near ambient pressure capability
Parking station with heating capabilities
Argon sputter gun for tip cleaning.

System 1 (SPECS) in Roldan's laboratory.

The original design - a joint effort between Prof. Roldan and SPECS

UHV-System 1 featuring in-situ laser-induced nanoparticle re-shaping

System 2: UHV surface science / magnetic optical Kerr effect (MOKE) system (SPECS GmbH).

An additional UHV system is available for sample synthesis, morphological (STM), and magnetic characterization (magneto-optic Kerr effect-MOKE in UHV). This system includes a load-lock chamber for quick sample transfer. In addition, a vacuum suitcase has been designed to transport samples under vacuum between different UHV systems.

Sample preparation chamber:

4-pocket electron beam evaporator with flux monitor (Oxford Sci.) for in-situ metal growth.
Hybrid atom/ion Plasma source (Oxford Sci.) for H₂, O₂, N₂ -> controlled production of ultrathin metal oxide films and removal of residual organics resulting from ex-situ nanoparticle synthesis.
Argon sputter gun for sample cleaning.

Surface analysis / MOKE chamber:

Mass spectrometer (HIDEN) for Temperature-Programmed Desorption (TPD).
Manipulator capable of radiative heating and liquid He cooling.
MOKE setup including glass finger for optical contact with sample while in UHV, ex-situ electromagnet (1.3 T) and laser setup for longitudinal and polar MOKE measurements.

Scanning Tunneling Microscopy chamber:

Variable Temperature Scanning Tunneling microscope (Aarhus-SPECS)
Parking station with heating capabilities
Argon sputter gun for tip cleaning.

UHV-System 2 for surface analysis and MOKE.

Vacuum suitcase for UHV sample transfer.