AES investigation of anode deposits in magnetron-type sputter ion pump

The composition of thin films deposited on the anode of a magnetron cell was studied by Auger electron spectroscopy (AES). The magnetron cell was constructed from a titanium cathode and a stainless steel anode. The cell was mounted on an UHV system with the ultimate pressure of 1 × 10−9 mbar. A stable discharge was established in nitrogen atmosphere at 10−7 mbar for 25 days. After the experiments, the electrodes were cut to small pieces and analyzed by AES. The results showed that a thin film of TiN slightly oxidized and contaminated by C was formed on the anode surface. The thickness of the film at the center of the anode was about 100 nm and it monotonously decreased towards the edges, indicating a rather uniform erosion of the cathode rod.