Modeling of the effects of dose, dose rate, and implant temperature on transient enhanced diffusion

Atomistic simulations are used to study the effects of implant parameters o n transient enhanced diffusion (TED). We analyze 10 keV Si implants in a wi de range of doses from 10(8) to 10(14) ions/cm(2), dose rates from 10(10) t o 10(14) ions/cm(2) s, and implant temperature from room temperature to 100 0 degrees C. Different regimes with different dependence of TED on these pa rameters are observed. For high doses, high dose rates, and low implant tem peratures, the Frenkel pairs are accumulated during ion implantation, and t he resulting damage is very dense. During the postimplant annealing, the re combination of Frenkel pairs is efficient, and the extra interstitials gene rated by the implanted ions provide the main contribution to the enhanced d iffusivity. For low doses, low dose rates, and high implant temperatures, t here is little interaction between neighboring cascades during annealing. T he recombination of Frenkel pairs is not complete, and many interstitials a nd vacancies from each cascade survive recombination and contribute signifi cantly to TED. (C) 1999 American Institute of Physics. [S0003-6951(99)02214 -7].