| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2018) | |
| Thin Films | Tuesday Sessions |
| Session TF-TuM |
| Session: | Innovations in the Development of Multifunctional Thin Films |
| Presenter: | Kazuhiko Mase, KEK, Japan |
| Authors: | T. Miyazawa, SOKENDAI, Japan M. Kurihara, Yokohama National University, Japan S. Ohno, Yokohama National University, Japan N. Terashima, Hirosaki University, Japan Y. Natsui, Hirosaki University, Japan H. Kato, Hirosaki University, Japan Y. Kato, Irie Koken Co., Ltd., Japan A. Hashimoto, National Institute for Materials Science, Japan T. Kikuchi, KEK, Japan K. Mase, KEK, Japan |
| Correspondent: | Click to Email |
We developed a novel non-evaporable getter (NEG) coating with an activation temperature as low as 133 °C, that is, a palladium/titanium coating with extremely low oxygen concentration (oxygen-free Pd/Ti coating) (Fig. 1) [1]. The substrate was coated with Ti, and then overcoated with Pd using sublimation under ultra-high vacuum conditions. The morphology and surface elemental composition of the Pd/Ti thin film were investigated with electron microscopes and X-ray photoelectron spectroscopy, respectively. The thicknesses of Ti and Pd films were approximately 1.3 μm and 50 nm, and the Ti film was completely overcoated by the Pd film. Ti and oxygen were found to be negligible on the oxygen-free Pd/Ti surface. The oxygen-free Pd/Ti coating was applied to formed bellows. The bellows was successively baked at 133 °C for 12 h, 176 °C for 3.5 h, and 200 °C for 3.5 h. After sealing off a turbomolecular pump from the vacuum system containing the bellows, the pressure reached values of 4.6 × 10−6 Pa, 1.7 × 10−7 Pa, and 6.1 × 10−8 Pa, respectively (Fig. 2). The pumping speeds of the bellows were estimated to be 0.028, 0.23, and 0.23 L s−1, respectively. These results demonstrate that oxygen-free-Pd/Ti deposition can be used as a new NEG coating for vacuum systems with a baking temperature of 133 °C or higher. Oxygen-free Pd/Ti coating was applied for a NEG pump that can be activated by baking at 150 °C for 12 h [2].
References
[1] T. Miyazawa, M. Kurihara, S. Ohno, N. Terashima, Y. Natsui, H. Kato, Y. Kato, A. Hashimoto, T. Kikuchi, and K. Mase, J. Vac. Sci. Technol. A, in press.
[2] T. Kikuchi, T. Miyazawa, H. Nishiguchi, K. Mase, AIP Conf. Proc., submitted.