Introduction

The Surface Characterisation Laboratory (SCL) is located in room 01.0.07-08. This laboratory is operated by the ID32 team and is available for the ESRF staff and users of ID32 on request on their experimental proposal. Users need to discuss planning of the lab utilisation in advance for their experiments with ID32 beamline staff.

The laboratory is dedicated to the preparation of surfaces and thin films. A variety of surface science tools are installed in two separate UHV systems:

• growth techniques with MBE and Pulsed Laser Deposition possibilities
• surface characterisation e.g. STM, Auger spectroscopy and LEED optics

Present work is focused on preparation of epitaxial high temperature superconductor thin films and transition metal oxide perovskite surfaces and interfaces and on the investigation of their structural and electronic properties.

Location of the Surface Characterisation Laboratory / SCL

SCL Equipment

The R2P2 System

The R2P2 system is a large multi-component UHV system (base pressure 1 x 10^-10 mbar) allowing sample transfer within UHV between various preparation and characterisation chambers. Samples freshly prepared by MBE or PLD can subsequently be studied in situ. For STM operation, the R2P2 table can isolated from floor motion by pneumatic vibration suspension.

The R2P2 system in more detail

The Small STM System

The small STM system comprises a UHV sample preparation chamber (base pressure 5 x 10^-11 mbar) and a standard Omicron STM.

The Small STM system in more detail

Transfer (Baby) Chamber

Design and construction of the new transfer 'baby' chamber were finished in April 2002. The baby chamber (total weight about 10 kg) allows sample transfer in UHV from the SCL to the ID32 beam line where the chamber can be mounted on the diffractometer. The hemispherical beryllium dome has an inner radius of 31.5 mm and a thickness of 0.4 mm and can accommodate our standard sample holders.

An ion pump is connected to the left side of the baby chamber - opposite the sample introduction port. An ion gauge allows controlling the pressure inside the chamber.

Picture of the baby-chamber with the Beryllium dom on top (designed by Tien-Lin Lee)

Examples for High Temperature Superconducting Thin Films grown by PLD

On the left hand side, YBa₂Cu₃O_7-d films of different thickness grown on SrTiO₃ substrates 5 x 10 mm in size are shown. Critical current densities and transition temperatures are determined by four probe transport measurements.