Transition Metals in a Cast‐Monocrystalline Silicon Ingot Studied by Silicon Nitride Gettering

Sun, Chang; Liu, AnYao; Samadi, Aref; Ciesla, Alison; Macdonald, Daniel

doi:10.1002/pssr.201900456

Cited by 9 publications

(5 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As mentioned previously, different distributions of Fe in the SiN x films have been observed. While Fe was detected across the entire bulk of the SiN x films in ref , an accumulation of metals (Fe, Cu, Ni, and Cr) at the SiN x /Si interface was observed in refs and . As it is unclear what caused these different impurity distributions, the effective d SiN x is not known.…”

Section: Resultsmentioning

confidence: 92%

“…It has been reported that silicon nitride (SiN x ) films fabricated by plasma-enhanced chemical vapor-deposition (PECVD), which are commonly used as passivation films and anti-reflection coatings in Si solar cells, can also induce impurity gettering effects at elevated temperatures. − In order to estimate the efficiency of the gettering process during cell fabrication and to optimize it, a better understanding of the gettering kinetics and mechanisms must be achieved.…”

Section: Introductionmentioning

confidence: 99%

“…2 Furthermore, segregation gettering aligns with previous observations that gettered Fe are distributed relatively uniformly within the bulk of the SiN x films. 3 However, later studies 5,6 showed that gettered metals can also aggregate at the SiN x /Si interface, which complicates the understanding of the gettering mechanism. Hence, further experimental evidence is needed to examine the conjectured predominance of the segregation gettering mechanism at low temperatures.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Impurity Gettering by Silicon Nitride Films: Kinetics, Mechanisms, and Simulation

Hameiri

Truong

et al. 2021

ACS Appl. Energy Mater.

Self Cite

View full text Add to dashboard Cite

Metallic impurities in the silicon wafer bulk are one of the major efficiency-limiting factors in silicon solar cells. Gettering can be used to significantly lower the metal concentrations. Although gettering by silicon nitride films has been reported in literature, much remains unknown about its gettering behaviors and mechanisms. In this study, the gettering kinetics and mechanisms of silicon nitride films, from both plasma-enhanced chemical vapor deposition (PECVD) and low-pressure chemical vapor deposition (LPCVD), are investigated. By monitoring the kinetics of iron loss from the silicon wafer bulk, it is confirmed that silicon nitride gettering takes place mainly via segregation, even at a low annealing temperature of 400 °C. Simulation of the gettering kinetics suggests the presence of an interfacial diffusion barrier in some cases, which slows down the transport of iron impurities from the silicon wafer bulk to the silicon nitride gettering regions. The activation energy of the segregation gettering process is estimated to be 0.9 ± 0.1 eV for the investigated PECVD silicon nitride film at 400–900 °C and 1.6 ± 0.5 eV for the investigated LPCVD silicon nitride film at 400–700 °C.

show abstract

Section: Resultsmentioning

confidence: 92%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Impurity Gettering by Silicon Nitride Films: Kinetics, Mechanisms, and Simulation

Hameiri

Truong

et al. 2021

ACS Appl. Energy Mater.

Self Cite

View full text Add to dashboard Cite

show abstract

“…As shown in The presence of some of these impurities has been previously reported in the cast-mono wafers. 54 Substitutional C has been shown to be another origin of the formation of low angle grain boundaries, as its concentration well correlates with the etch pit density in castmono wafers. 45 Moreover, Ohno et al 44 and holes (σ p ).…”

Section: Temperature Sensitivity Of Crystallographic Defectsmentioning

confidence: 99%

Temperature sensitivity maps of silicon wafers from photoluminescence imaging: The effect of gettering and hydrogenation

Nie¹,

Chin²,

Soufiani³

et al. 2022

Progress in Photovoltaics

Self Cite

View full text Add to dashboard Cite

The operating temperature has a critical impact on the electrical performance of solar cells. It has been shown that the temperature coefficient is not uniform across devices and often varies between different regions due to the inhomogeneous distributions of defects. In this study, temperature‐dependent photoluminescence imaging measurements are used to assess the influence of different processes such as gettering, firing and advanced hydrogenation on the temperature‐dependent electrical performance of cast‐mono silicon wafers. It is found that the height of the wafer within the ingot impacts the response of the temperature coefficient to different fabrication processes. Advanced hydrogenation is found to reduce the temperature sensitivity, more than expected solely from the improvement in implied open‐circuit voltage. Crystallographic defects are found to be the least temperature sensitive regions, indicating that their detrimental impact is reduced at higher operating temperatures. The interesting low temperature sensitivity in the defective regions is further investigated using hyperspectral photoluminescence imaging measurements and atom probe tomography. It is suggested that the reduced sensitivity is due to impurities decorating crystallographic defects.

show abstract

“…In this work, we conducted a preliminary and comprehensive theoretical calculation of SiN x . At the same time, considering that current classic MD potentials are not suitable for SiN x simulations due to efficiency and accuracy [27][28][29][30][31][32], it is of great interest to train a new potential to describe the interatomic interactions.…”

Section: Introductionmentioning

confidence: 99%

High-Accuracy Neural Network Interatomic Potential for Silicon Nitride

Zhang

et al. 2023

Nanomaterials

View full text Add to dashboard Cite

In the field of machine learning (ML) and data science, it is meaningful to use the advantages of ML to create reliable interatomic potentials. Deep potential molecular dynamics (DEEPMD) are one of the most useful methods to create interatomic potentials. Among ceramic materials, amorphous silicon nitride (SiNx) features good electrical insulation, abrasion resistance, and mechanical strength, which is widely applied in industries. In our work, a neural network potential (NNP) for SiNx was created based on DEEPMD, and the NNP is confirmed to be applicable to the SiNx model. The tensile tests were simulated to compare the mechanical properties of SiNx with different compositions based on the molecular dynamic method coupled with NNP. Among these SiNx, Si3N4 has the largest elastic modulus (E) and yield stress (σs), showing the desired mechanical strength owing to the largest coordination numbers (CN) and radial distribution function (RDF). The RDFs and CNs decrease with the increase of x; meanwhile, E and σs of SiNx decrease when the proportion of Si increases. It can be concluded that the ratio of nitrogen to silicon can reflect the RDFs and CNs in micro level and macro mechanical properties of SiNx to a large extent.

show abstract

Transition Metals in a Cast‐Monocrystalline Silicon Ingot Studied by Silicon Nitride Gettering

Cited by 9 publications

References 29 publications

Impurity Gettering by Silicon Nitride Films: Kinetics, Mechanisms, and Simulation

Impurity Gettering by Silicon Nitride Films: Kinetics, Mechanisms, and Simulation

Temperature sensitivity maps of silicon wafers from photoluminescence imaging: The effect of gettering and hydrogenation

High-Accuracy Neural Network Interatomic Potential for Silicon Nitride

Contact Info

Product

Resources

About