Abstract
The trapping of Si interstitials by C
+ implantation has been quantified by following the evolution of EOR defects during thermal annealing. Si (100) n-type wafers have been preamorphised by the implantation of 150 keV Ge
+ ions to a dose of 2 × 10
15 ions/cm
2 to form a 175 nm thick amorphous layer, followed by C
+ implantation at 65 keV (
R
p = 175 nm to doses ranging from 3 × 10
13 ions/cm
2 to 3 × 10
15 ions/cm
2. All samples were then annealed at 1000°C for 15 s. These structures have been investigated by RBS, TEM and SIMS. The mean radius of the EOR loops monotonically decreases with increasing dose of C
+ ions while their density increases. The number of Si self-interstitials stored in the loops also decreases with increasing carbon dose. This effect is associated with the capture of Si self-interstitials by SiC complexes. The effective trapping efficiency of carbon is about 1.18 interstitials per carbon atom, which is consistent with values obtained from studies of B transient enhanced diffusion.