Boron ion particles sputtered from boron films deposited on graphites

Boron films were deposited on pyrolytic and isotropic graphites by vapor de position at different deposition rates. The particles sputtered from these films were measured directly by the QMS during 5 keV Dg beam irradiation wi th a flux of 2 x 10(21) D/m(2) s. It was found that the sputtered particles were in the form of boron ion and neutral. The boron ion showed a differen t behavior from the neutral. The ion signal had a peak value at the beginni ng of each shot. It also depended on the conditions of the substrates and t he deposition rate. These dependencies might be associated with the existen ce of oxygen on the surface. (C) 1998 Elsevier Science B.V. All rights rese rved.