Thin Film Deposition @ University of Alabama
Used for: | Thin Film Fabrication and Characterization |
The MRSEC uses a variety of physical vapor deposition systems within the MINT Center and the MFF. MRSEC funds were used to construct two custom-built UHV sputtering systems with 6 and 8 sputtering guns, respectively, using dc or rf sources. The main chambers reach a base pressure <10-9 Torr, with auxiliary load lock chambers for high throughput. Films can be deposited at temperatures up to 750ºC, while the sample is being rotated to ensure uniformity or cosputtering to produce alloyed films. The systems have a variety of in-situ characterization capabilities, including Auger electron spectroscopy and reflection high-energy electron diffraction (RHEED).
A shared Shamrock seven-source planetary sputtering system is also available in the MFF Facility. The system is completely automated, ensuring reproducibility between depositions. The seven sputtering targets can be operated in DC, AC or RF modes, as well as co-sputtered, which provides flexibility in gradually changing composition. A magnetic substrate holder provides easy axis orientation for soft magnetic films, including in situ rotation of the field relative to the substrate.
A six-target high vacuum (base pressure ~10-8 Torr) laser deposition system with a load-lock chamber is also in use in the MINT Center. The system has an in situ differentially-pumped RHEED system for surface characterization, with chamber pressure as high as 200-500mTorr. A low-energy ion gun is available for surface cleaning. This advanced laser deposition system - referred to as a laser molecular beam epitaxy system (laser MBE) - is used primarily for the controlled, layer-by-layer growth of multilayers and artificially structured materials. A smaller four-target laser deposition setup, without in situ analysis, is available for more routine deposition of single and bilayer films at elevated temperatures. The two systems share an excimer laser (Lambda Physik, Model COMPexPro 201, 248 nm radiation) for deposition, with an appropriate optical setup to switch between them.