UHV evaporation chamber for growth and in-situ characterization of ultrathin magnetic films

Contact: Gianluca Gubbiotti

A UHV chamber, specially designed to be directly interfaced with the optical table for in-situ Brillouin light scattering (BLS) and Magneto-optic Kerr effect (MOKE) measurements, is operative and used by the IOM researchers to growth and study structural and magnetic properties of ultrathin magnetic films deposited either on metallic or semiconductor substrates. As shown in the picture, it is a compact chamber mounted on top of a mobile frame, equipped with standard UHV tools, such as e-beam evaporators, quartz micro-balance, LEED-Auger apparatus, RHEED, load-lock system. A horizontal XYZ manipulator, with primary and secondary rotations, is used to position the evaporated film at the end of the so called BLS tube which is a protuberance about 20 cm long and 10 cm in diameter, terminating with a glass viewport for BLS and SMOKE measurements.

The temperature of the specimen can be varied in the range 110-1400 K. The whole frame can be translated just aside the BLS optical table, inserting the BLS tube within the poles of an external four-inches electromagnet. The sample holder allows to measure the spin wave frequency as a function of the both the incidence angle of light and the in-plane angle of the applied magnetic field, with field intensity up to 6 kOe. MOKE hysteresis curves can be measured in the longitudinal configuration to determine the magneto-crystalline anisotropy and its evolution with the film thickness.