RBS ANALYSIS OF THIN MOSIX FILMS - CORRELATION BETWEEN STOICHIOMETRY AND SOME FEATURES OF SPUTTERING

The well separated peaks in the RBS spectrum of thin MoSi(x) films per mit the determination of the atomic area densities of both components with fairly good accuracy to obtain the film composition x within erro r limits of +/- 3%. Taking advantage of this fact we studied the subst rate radial distributions of the composition of MoSi(x) films deposite d by planar dc magnetron sputtering from a circular compound target. T he RBS measurements were confirmed by cross-checks with AES profilings . The distributions indicate a remarkable asymmetry in the sputtering characteristics of Si and Mo, respectively, which is interpreted to be due mainly to differences in the angular function of the target emiss ion. By a simulation procedure the shape of these angular functions ca n be calculated. It results that in the sputtering of Mo atoms, by con trast to Si, there is a higher amount of emission events into directio ns far from the target normal.