| AVS 61st International Symposium & Exhibition | |
| Vacuum Technology | Tuesday Sessions |
| Session VT-TuM |
| Session: | Gas Dynamics, Modeling, and Pumping Systems |
| Presenter: | Fabrizio Siviero, SAES Getters, Italy |
| Authors: | F. Siviero, SAES Getters, Italy G. Bongiorno, SAES Getters, Italy L. Caruso, SAES Getters, Italy A. Gallitognotta, SAES Getters, Italy L. Viale, SAES Getters, Italy E. Maccallini, SAES Getters, Italy P. Manini, SAES Getters, Italy |
| Correspondent: | Click to Email |
Non Evaporable Getter (NEG) pumps are commonly used when large pumping speeds for H2 and active gases (i.e., H2O, O2, CO, CO2) are required. The NEG pumps are very small, lightweight, with reduced magnetic interference, cause no vibration, and consume negligible power. Thanks to these qualities NEG pumps are widespread in many UHV applications.
Nevertheless, some factors still limit an even wider diffusion of NEG pump technology, mainly related to the topics of particle release and gas evolution during activation. Indeed, as a precaution, NEG pumps are generally not used in application requiring particle-free environment. Only recently, measurements performed at a large accelerator facility have shown the compatibility of St172® alloy sintered getters in particle free environments, i.e RF cavities, after suitable treatments. Also, it is well known during getter activation hydrogen as well as other physisorbed species are desorbed causing pressure increase up to the 1e-6 mbar range. In some applications this is seen as a problem due, for example to constraints in pumping efficiently hydrogen away from long and narrow chambers.
These topics will be discussed based on recent outcomes of research activities carried out in SAES R&D labs to address these issues. New alloys, belonging to the ZAO® family, and new production processes have been developed, showing interesting characteristics. Among them we highlight intrinsically reduced particle release, lower hydrogen equilibrium isotherms and more efficient management of the gas load during activation. These properties are combined with a new pump design, even more compact and simpler to install than before, with the aim of providing an enlarged community of users with smarter solutions to their vacuum needs.