Design and realization of a sputter deposition system for the in situ and in operando use in polarized neutron reflectometry experiments: Novel capabilities

摘要

Recently, the design and realization of a sputter-deposition system for in situ and in operando polarized neutron reflectometry (PNR) was reported. The device allows magnetic thin films and heterostructures to be grown, while the sample remains aligned in the neutron beam for PNR. By now, it has been applied in experiments that investigated the magnetic and structural properties of thin Fe and Pd/Fe/Pd heterostructures as a function of the layer thickness. Here, we report on significant upgrades of the deposition system with advanced thin film growth and measurement capabilities. These include improvements to the generation of the vacuum to realize ultra-high-vacuum (UHV) conditions. A base pressure below 5 ×10~(-9) mbar can now be obtained within less than one day of pumping time. To allow experiments over a wide range of temperatures, the system was upgraded to include a cryo-furnace. It allows the sample to be cooled or heated in the range of 10 K to 1000 K for both applications, sample growth and measurement. Further, a new magnetic coil setup with soft iron yoke was designed which can realize a homogeneous in-plane magnetic field of up to 300 mT and electric fields at the sample position.