Vacuum getter pump with thermo-sedimentational activation

Abstract

The new ultra- and extreme high vacuum getter pump with an ultimate pressure of 10−14 mbar and the absence of free solid particles is also distinguished by its simplicity of design and low-cost getter material. Unlike known getter pumps, a new, dust-free solution to the problem of capturing gases with getters reactants is achieved through the use of two types of sorbing boundaries, gas/solid and gas/melt, as well as due to thermo-sedimentational activation of the getter material.

1 . A getter vacuum pump or a pumping system in the form of two such pumps, wherein either of said pumps is a steel cylindrical container with a flange, with getter material inside and an external heater, and wherein said pumps create a pressure of the order of 10 −10 -10 −14  mbar in the evacuated vacuum chamber without generating free solid particles. 
     
     
         2 . The getter vacuum pump according to  claim 1 , wherein the getter material is Li alloys with Ca, Sr and Ba in the molten state, which triggers the process of sedimentational cleaning of the gas/melt interface from the solid product formed thereon, thus accelerating the sorption kinetics and preventing contamination of the vacuum chamber with solid particles. 
     
     
         3 . The getter vacuum pump according to  claim 2 , wherein only alloys with a liquidus temperature of 200° C. or less are used, such as Li x (Sr y Ba 1-y ) 1-x , where 0.8≤x≤0.9 and 0≤y≤1, or alloys Li x Ca 1-x , where 0.8≤x≤0.9 and where Ca is doped with Sr and Ba, which reduces the ultimate pressure to 10 −11  mbar. 
     
     
         4 . The pumping system in the form of two getter pumps according to  claim 1 , where in turn each of them is in a state of pumping out gases with the getter material at T room , and the other is at this time disconnected from the vacuum chamber to restore the functionality of the getter material by melting it and sedimentational cleaning of the surface, which, taken together, reduces the ultimate pressure in the system to 10 −14  mbar. 
     
     
         5 . The getter vacuum pump according to  claim 3 , where in addition to the alloys specified therein, the eutectic alloy Li—10 at % Ce is used, and the alloys are also allowed to be alloyed with magnesium, provided that the liquidus temperature of the alloys does not exceed 250° C., thereby guaranteeing the ultimate pressure at the level of 10 −10  mbar. 
     
     
         6 . The getter vacuum pump according to  claim 5 , which in its vertical position, and more preferably when installed on a “swing”, or when connected to a rotation system with an inclination, is used for sorption purification of noble gas loaded into this pump at the required pressure, up to pressures of tens of bar.