Carbon in silicon: Modeling of diffusion and clustering mechanisms

Abstract

Carbon often appears in Si in concentrations above its solubility. In this article, we propose a comprehensive model that, taking diffusion and clustering into account, is able to reproduce a variety of experimental results. Simulations have been performed by implementing this model in a Monte-Carlo atomistic simulator. The initial path for clustering included in the model is consistent with experimental observations regarding the formation and dissolution of substitutional C-interstitial C pairs (C s-C i). In addition, carbon diffusion profiles at 850 and 900°C in carbon-doping superlattice structures are well reproduced. Finally, under conditions of thermal generation of intrinsic point defects, the weak temperature dependence of the Si interstitial undersaturation and the vacancy supersaturation in carbon-rich regions also agree with experimental measurements.

IR studies of the oxygen and carbon precipitation processes in electron irradiated tin-doped silicon

“…In particular, the recovery of C substitutional atoms observed in the spectra by the increase of the intensity of the 605 cm −1 was connected with the formation of C N (Si I ) M complexes. These complexes act [66] as sources of these additional C atoms either involved in reactions with Si I 's and V or/and transformed to SiC precipitates. Notably, C and Si I clustering leading in general to the formation of C N (Si I ) M complexes has been extensively discussed in the literature [66,126,127].…”

“…These complexes act [66] as sources of these additional C atoms either involved in reactions with Si I 's and V or/and transformed to SiC precipitates. Notably, C and Si I clustering leading in general to the formation of C N (Si I ) M complexes has been extensively discussed in the literature [66,126,127]. In particular, it was suggested [66] that upon increasing the annealing temperature, various reactions take place involving V, Si I as well as C s and C i leading to the formation of C N (Si I ) M complexes.…”

“…Considering co-doping pairs (C, Sn) in Si will help us gain a more complete understanding of mechanisms that govern O and C precipitation processes as well as the ways that Sn isovalent dopants affect these processes. Importantly, since V and Si I play [61][62][63][64][65][66][67] a key role in the O and C precipitation processes we can reversibly deepen our understanding on the mechanisms through which these primary defects affect the agglomeration of O and C impurities in Si treated at elevated temperatures. Also it could enhance the opportunities for technological improvements of Si providing an engineering strategy for thermal defects that could be employable to analogous systems.…”

Effect of dose and size on defect engineering in carbon cluster implanted silicon wafers

“…33) Note that the model for the formation of C=I clusters is incorporated in the TCAD Sentaurus Process. 32,33) This cluster model describes a complex of carbon and Si self-interstitials in the form of C m I n (e.g., C 6 I 6 and C 6 I 7 ). The reaction of a C m I n complex can be expressed by the following tapping and emission reactions of interstitial carbon (C i ) and Si self-interstitials (I): Figure 7 shows the distribution of carbon (black) and Si self-interstitials (red) simulated by using the KMC code of TCAD in the implanted region of the carbon clusters after epitaxial growth and heat treatment.…”

Carbon-Related Defects in Si:C/Silicon Heterostructures Assessed by Deep-Level Transient Spectroscopy

“…[14][15][16][17] These defect pairs can act as nuclei for further carbon clustering by trapping more C atoms, according to the reaction schemes proposed in the literature. [18][19][20][21] In this paper, a Deep-Level Transient Spectroscopy (DLTS) analysis is performed to address this issue, since some of the C-related defects correspond with levels in the bandgap of silicon. Monitoring these levels provides more insight into the microscopic processes going on in the Si:C epi layer and in the substrate depletion region underneath.…”