Highly stabilized sputter deposition of YBa2Cu3O7

A method of stabilizing and homogenizing the plasma during on-axis high-pressure dc sputter deposition of YBa2Cu3O7 is introduced, which leads to improved reproducibility and uniformity of the deposition process. The plasma is monitored and controlled via optical emission spectroscopy. Strong changes of the plasma intensity and intensity profile above the target are observed in the standard sputter process, which lead to unstable and inhomogeneous deposition of high Tc material. These changes are counteracted by adequate variation of the composition of the process gas (Ar/O2). The intensity of the plasma flicker is thus reduced by a factor of 4–5, long term drifts in the plasma intensity, and arcing of the plasma are eliminated.