Pumping Experiment of Water on B and LaB6 Films with Electron Beam Evaporator

摘要

Pumping characteristics of water vapor on boron and lanthanum hexaboride filmsformed with an electron beam evaporator have been investigated in high vacuum of a pressure region between 10(exp -4) and 10(exp -3) Pa. Measured initial maximum pumping speeds of water for fresh B and LaB6 films on substrates with a deposition amount from 2.3 x 10(exp 21) to 6.7 x 10(exp 21) molecules m (exp -2) are 3.2 to approximately 4.9 m/s, and maximum saturation amounts of adsorbed water on these films are 2.9 x 10(exp 20) to approximately 1.3 x 10(exp 21) H2O molecules/sq m.