Sputtering Process of Sc_xAl_1−xN Thin Films for Ferroelectric Applications

Several key sputtering parameters for the deposition of Sc_xAl_1−xN such as target design, sputtering atmosphere, sputtering power, and substrate temperature are reviewed in detail. These parameters serve a crucial role in the ability to deposit satisfactory films, achieve the desired stoichiometry, and meet the required film thickness. Additionally, these qualities directly impact the degree of c-axis orientation, grain size, and surface roughness of the deposited films. It is systematically shown that the electric properties of Sc_xAl_1−xN are dependent on the crystal quality of the film. Although it is not possible to conclusively say what the ideal target design, sputtering atmosphere, sputtering power, and substrate temperature should be for all sputtering processes, the goal of this paper is to analyze the impacts of the various sputtering parameters in detail and provide some overarching themes that arise to assist future researchers in the field in quickly tuning their sputtering processes to achieve optimum results.