On the Properties of the Intrinsic Point Defects in Silicon: A Perspective from Crystal Growth and Wafer Processing

Vacancy self-trapping during rapid thermal annealing of silicon wafers

“…In both cases, it will be assumed that the local BMD density following a nucleation-growth anneal is closely related to the local vacancy concentration at the beginning of the anneal. 5,7 In other words, the BMD density is not explicitly considered but rather implicitly modeled via the vacancy distribution. In the point defect picture, only the diffusion and recombination of self-interstitials and vacancies are considered explicitly, so that…”

“…Following RTA, regions of the wafer that have a residual vacancy concentration above a critical value, C V * ϳ͑1-3͒ ϫ 10 12 cm −3 , exhibit rapid formation of oxide precipitate nuclei in subsequent nucleation-growth thermal treatments. 5,7 Recently, RTA experiments under certain annealing protocols, namely, high temperatures and cooling rates, demonstrated unusual BMD density distributions in which the maximum BMD density is observed to lie somewhere in between the wafer edge and the center, leading to a so-called m-like profile. 8 Given the importance of BMD density distributions in silicon technology, we specifically address this density variation here by applying a recently developed model for defect diffusion and aggregation.…”

“…3,4 It has been elegantly demonstrated that relatively straightforward manipulation of vacancy populations by rapid thermal annealing ͑RTA͒ of Czochralski-grown wafers can be used to precisely tailor the distribution of oxide precipitates in order to create a "denuded zone" near the wafer surface ͑corresponding to low vacancy concentration͒ while producing a high precipitate density in the wafer bulk ͑high vacancy concentration͒. 5,6 This profile results from the combination of point defect diffusion to and from the wafer surface and point defect recombination in the wafer bulk. Following RTA, regions of the wafer that have a residual vacancy concentration above a critical value, C V * ϳ͑1-3͒ ϫ 10 12 cm −3 , exhibit rapid formation of oxide precipitate nuclei in subsequent nucleation-growth thermal treatments.…”

“…These complexes are thought to be the building blocks for BMDs in Czochralski silicon wafers. 5 The model in Eqs. ͑1͒ and ͑2͒ was extended to include reversible reactions between vacancies and oxygen, 7 V +O i ↔ OV +O i ↔ O 2 V, in addition to vacancy aggregation.…”

Kinetic Monte Carlo simulations for transient thermal fields: Computational methodology and application to the submicrosecond laser processes in implanted silicon

“…Free defect migration energies were taken from the work of Pelaz et al [6], whilst the D 0 values, which also determine the frequency prefactors for the random jump events by means of Eq. (9), were fixed in order to achieve the proper diffusivity values near the silicon melting point (D [22]). This strategy allows a reasonable physical setting of free defect parameters in the whole temperature range reached during laser annealing processes.…”