Effects of end-of-range dislocation loops on transient enhanced diffusion of indium implanted in silicon

Transient enhanced diffusion of indium implanted in silicon is studied in t he presence of the end-of-range (EOR) damage layer. To investigate the effe ct of EOR defects on the indium diffusion, the samples that were implanted with indium at a high dose (1x10(13)-5x10(14)/cm(2)) sufficient to produce the amorphous layer were prepared. Transmission electron microscopy measure ments and Rutherford backscattering spectrometry reveal the amorphization t hreshold of indium implantation is around 5x10(13)/cm(2) for 200 keV, In-11 5(+) implanted with 100 mu A/cm(2) beam current density at room temperature . These results are consistent with Monte Carlo simulation of implantation. Monte Carlo simulations indicate the deviation from the plus one model due to the mass effect of indium. After amorphization, following both RTA at 1 000 degrees C and furnace anneal at low temperature (650 and 850 degrees C) in nitrogen ambient showed the formation of extrinsic EOR dislocation loop s below the original amorphous/crystalline interface. During this process, strong segregation of indium toward the EOR dislocation loops is clearly ob served. The profile shift of indium at a concentration of 1x10(17) atoms/cm (3) is not proportional to the implanted dose. Since most interstitials con dense into EOR dislocation loops, diffusivity enhancement of indium is not proportional to the implant dose above amorphization threshold. (C) 2000 Am erican Institute of Physics. [S0021-8979(00)07521-6].