A new hybrid molecular pump with large throughput

A new design of a hybrid molecular pump with large throughput is described in this paper. It can be operated within the pressure range of 1 to 10⁻¹⁰ Torr for a clean vacuum with a maximum throughput of 10 Torr l/s. The maximum inlet pressure is above 1 Torr, which is almost 100 times higher than that of a conventional turbomolecular pump (TMP). The pump is constructed with ten disks of a TMP and nine disks of a Siegbahn molecular pump in series, with a clearance of 0.5 mm between rotating and stationary parts. The compression ratio for H₂ is over 700, which is equivalent to that of a TMP with 31 disks.