Vacuum chambers sputter-coated with a thin film (approx. 1.5 μm) of a getter material, and subsequently exposed to ambient air, have been found to recover a pumping action after 'in situ' bakeout. Coatings of Ti, Hf, Zr have been initially produced and studied, followed by their binary quasi-equiatomic alloys TiHf, HfZr, TiZr. All these coatings display activation at temperatures lower than 400°C, as observed by means of X-ray photoelectron spectroscopy, electron stimulated desorption (ESD), pumping speed and ultimate pressure measurements. The lowest activation onset temperature, about 200°C, has been measured for the quasi-equiatomic TiZr alloy. A further activation temperature decrease has been achieved for TiZr based ternary alloys/compounds, which are currently being investigated.
Benvenuti, C., Cazeneuve, J. M., Chiggiato, P., Cicoira, F., Santana, A. E., Johanek, V., Ruzinov, V., & Fraxedas, J. (1999). Novel route to extreme vacua: the non-evaporable getter thin film coatings. Vacuum, 53(1-2), 219-225. https://doi.org/10.1016/S0042-207X(98)00377-7