RANGES IN SI AND LIGHTER MONO AND MULTIELEMENT TARGETS

In the present review we describe experimental range studies for ions implanted into Si and lighter mono and multi-element targets. The experimental results are compared with current theories, in particular with the Ziegler, Biersack and Littmark (ZBL) calculations. It is found that for Si targets at implanted energies from 10 to 390 keV and for a large set of ion-Si combinations (29 less than or equal to Z(1) less than or equal to 83) there is overall a good agreement (better than 10%) between the experimental data and the ZBL calculations. However, for Au, Yb and Eu, significant theoretical-experimental differences are found when these ions are implanted at energies lower than 70 keV. The disagreement is removed when a cut-off in the interatomic potential is performed. On the other hand, systematic range studies performed in C, B, Be, SiC and polymer target films have shown that whenever medium-heavy ions are implanted in an energy range of 10 keV-7.5 MeV the experimental data are underestimated by the theory by as much as 40%. Using a simple model which takes into account the influence of the inelastic collisions on the nuclear stopping power this last difference is removed and a very good agreement is achieved between the calculated and experimental results. Finally the status for H, B and Li deep implants into Si at energies where the electronic stopping power reaches its maximum, is also reviewed.