Sample contamination caused by sputtering during ion implantation

Data is presented which shows that both forward and back sputtering can be the cause of heavy metal surface contamination of samples during ion implantation. Rutherford backscattering is used to show that contamination levels can be in excess of 1 and 0.02% of the implanted dose for forward and back sputtering, respectively. It is suggested that ion implantation equipment using mechanical sample scanning is particularly susceptible to this cause of contamination. (author)