Sputtering rate of lead, tin and germanium tellurides with low energy argon ions

Abstract

Sputtering of PbTe, SnTe, and GeTe crystal samples by low-energy Ar+ ions are investigated, and the sputtering rate vsp of the studied compounds, as well as its dependence on both the composition of crystal matrix and the sputtering energy are determined. It is found that under the same conditions the sputtering rate in the sequence of GeTe-SnTe-PbTe telluride compounds increases when their average atomic weight increases. This phenomenon is explained by changes in the surface binding energy of metal atoms in lead, tin and germanium tellurides. It is shown that for all compounds the sputtering rate also increases with the increase in the sputtering energy. In the energy range from 160 to 550 eV,this increase is almost linear. The coefficients of change in the sputtering rate with energy dvsp/dE are calculated. The surface density of Ar+ ion-induced structures and the relative area of the sputtered surface covered by these structures are determined for the natural lateral surfaces of a PbTe crystal grown from melt by the Bridgman method as a function of sputtering energy. It is shown that both studied parameters decrease exponentially with increasing the sputtering energy.