Altered Layer Formation and Sputtering Yields for 5 Kev Ar+ Bombardment of Moo3 and Wo3.
Driscoll-TJ; McCormick-LD; Lederer-WC
Surf Sci 1987 Apr; (187):539-558
This paper describes a study of the effects on moo3 and wo3 due to ion bombardment using parameters typical of sputter profiling (5 kev ar+ at approximately 10 ua/cm2) using proton-induced x-ray emission and x-ray photoelectron spectroscopy. During the first 2 x (10)15 to 2 x (10)16 ions/cm2 of sputtering, structurally and chemically altered regions form. The structurally altered regions are due to amorphization. The chemically altered regions consist of both stoichiometric and nonstoichiometric oxides with lower oxygen contents than the original trioxides, as well as trioxide for moo3 and elemental w and/or w3o for wo3. The thicknesses of the chemically altered regions are comparable to the range of the incident ions for wo3 and about five times as large as the range for moo3. The possibility of distortions in sputter profiles of complex oxide films due to different sputtering yields for component oxides was evident in the measured sputtering yields of 2.1, 2.5, and 3.5 Atoms/ion for ta2o5, moo3, and wo3, respectively, for normally incident ions.
Surf. Sci., No. 187, Apr. 4, 1987, PP. 539-558