End station: Spin-resolved XPS

The XPS system is equipped with a 40 degree acceptance angle hemispherical analyzer with mean radius of 140 mm coupled to a 25 kV mini-Mott spin polarimeter. The spin detector together with the electrostatic transfer optics provide a Sherman function close to 0.17 and the figure of merit 1.4x10^-4. These parameters make accessible a variety of spin-resolved experiments whose limiting factor is either the low intensity and/or a low polarization.

The system has the following basic characteristics:

• Angle integrating electron energy analyzer with spin detection
• Fast load lock sample introduction
• Sample cooling and heating approximately 10-1000 K (ask for specifics)
• Two e-beam evaporators
• Two Knudsen cell evaporators
• Crystal monitor
• e-gun (0-5 keV)
• Sputter gun
• LEED
• Magnetization coil
• Drain current measurement

The analyzer is at a 60 degree angle with respect to the photon beam and nominal working distance is 13.8 mm.

Samples

Samples need to have a minimum 4x4 mm measurement surface, for smaller sizes contact us in advance. Polycrystalline samples need to be 3 mm thick so that they can be filed in vacuum to expose clean surfaces. Single crystals that need to be fractured in vacuum need to be 5 mm high. Single crystals that need to be sputter cleaned can have up to 10 mm diameter, and be typically 3 mm thick. Samples not falling in the above categories might still be measurable but the beam line staff should be contacted for further information.

Sample surfaces can be prepared in the load lock by scraping or cleaving. Sputtering and annealing can be done in the main chamber. Thin film growth can be done by utilizing one or several of the two Knudsen plus two e-beam evaporators installed on the main chamber. A water cooled crystal monitor is installed for calibration of evaporation rates. The manipulator can hold two sample holders at a time.

The sample holders have a usable surface of 14*15 mm*mm. Currently existing sample holders are made of copper.