Design and Operation of Evapor-ion Pumps

Abstract

A new type of high vacuum pump has been developed which makes possible the elimination of organic vapors and high vapor pressure materials from vacuum systems, without using coolant traps or baffles. This pump utilizes the gettering action of continuously evaporated titanium in conjunction with ion pumping. Some pumping speeds achieved are: 7000–8000 liters/sec at 3×10⁻⁶ mm of Hg for hydrogen, 6500–7500 liters/sec at 1.5×10⁻⁶ mm for nitrogen and oxygen, approximately 9 liters/sec at 4×10⁻⁶ mm for argon, and approximately 4 liters/sec at 3×10⁻⁵ mm for helium. The lowest pressure obtainable is about 2×10⁻⁷ mm of Hg. Dependence of pumping speeds on the temperature of the gettering surface, the pressure and the rate of evaporation of titanium is given.