Gettering of platinum by cavities induced in silicon by high energy implantation of HE ions

Pt diffused diodes (p+ n n+ junctions) were manufactured on 75 μm n-type epitaxial Si wafers. Gettering of Pt by 3.1 MeV He-implantation induced defects was performed. The fleunce was 1017 He/cm2. A post thermal annealing at 1050°C for 2 h gave rise to formation of a 0.2 μm cavity layer at the predicted projected range (Rp) as measured by XTEM (cross sectional transmission electron microscopy). SIMS (secondary ion mass spectroscopy) crater profiles of both B and Pt revealed that the cavities are efficient sites to trap Pt atoms.