Turbodrag pumps

11/01/1997

Turbodrag pumps

These maintenance-free, oil-free, vibration-free, magnetically suspended bearing turbodrag pumps - the TMH 1600 MC, TMH 1000 MC, and TMH 400 MC - are designed for processes such as CVD, reactive ion etching, sputtering, ion implementation, and diffusion. The pumps feature noncontact magnetic bearings that eliminate the need for lubricants. A proprietary internal pump surface coating protects against corrosion, and the temperature management system prevents the condensation of aggressive gases, maximizing uptime. The pumps combine a multiple-stage turbomolecular pump and Holweck-type molecular drag pumping system to permit a high foreline pressure of 12 mbar, an ultimate pressure of 10-10 mbar, and a compression ratio of up to 108 for helium. This allows the use of a backing pump up to 100? smaller than with conventional turbopumps. A powerful digital controller provides control of the magnetic bearings and pump performance, and ensures continuous pump operation in the event of a power failure. Pfeiffer Vacuum Technology Inc., Nashua, NH; ph 603/578-6500, fax 603/578-6550.