Diffusion of indium and gallium in Cu(In,Ga)Se2 thin film solar cells

Lundberg, Olle; Lu, Jun; Rockett, Angus; Edoff, Marika; Stolt, Lars

doi:10.1016/s0022-3697(03)00127-6

Cited by 120 publications

(67 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Indeed, segregated Cu (2-x) Se has been associated with an increased Ga and In inter-diffusivity [19,29]. Schroeder et al [14] showed that when CuInSe 2 is grown epitaxially with overstoichiometric Cu supply on a Ga-rich substrate, Ga diffuses from the substrate to the film, to the extent that the final CGI never exceeds 1.…”

Section: Discussionmentioning

confidence: 99%

“…PDT is in fact performed at a temperature approximately 100 °C below the deposition temperature, and the presence of alkali elements is known to further reduce group-III element diffusivities [19]. PDTs were reported to modify the surface and GB chemical composition at the surface [20] and grain boundaries [21] only in regions limited to a few nanometers.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Voids and compositional inhomogeneities in Cu(In,Ga)Se₂ thin films: evolution during growth and impact on solar cell performance

Avancini

Keller

Carron

et al. 2018

Science and Technology of Advanced Materials

View full text Add to dashboard Cite

Structural defects such as voids and compositional inhomogeneities may affect the performance of Cu(In,Ga)Se2 (CIGS) solar cells. We analyzed the morphology and elemental distributions in co-evaporated CIGS thin films at the different stages of the CIGS growth by energy-dispersive x-ray spectroscopy in a transmission electron microscope. Accumulation of Cu-Se phases was found at crevices and at grain boundaries after the Cu-rich intermediate stage of the CIGS deposition sequence. It was found, that voids are caused by Cu out-diffusion from crevices and GBs during the final deposition stage. The Cu inhomogeneities lead to non-uniform diffusivities of In and Ga, resulting in lateral inhomogeneities of the In and Ga distribution. Two and three-dimensional simulations were used to investigate the impact of the inhomogeneities and voids on the solar cell performance. A significant impact of voids was found, indicating that the unpassivated voids reduce the open-circuit voltage and fill factor due to the introduction of free surfaces with high recombination velocities close to the CIGS/CdS junction. We thus suggest that voids, and possibly inhomogeneities, limit the efficiency of solar cells based on three-stage co-evaporated CIGS thin films. Passivation of the voids’ internal surface may reduce their detrimental effects.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Voids and compositional inhomogeneities in Cu(In,Ga)Se₂ thin films: evolution during growth and impact on solar cell performance

Avancini

Keller

Carron

et al. 2018

Science and Technology of Advanced Materials

View full text Add to dashboard Cite

show abstract

“…[5][6][7][8] These two cannot be practically disentangled in a compound such as CIGS where the cation-III-atoms compete for the same sublattice positions. In and Ga diffusion has been suggested to proceed in the cation sublattice via vacancies again due to variations in diffusivity with respect to the composition of the sample.…”

Section: Indium Mass Transportmentioning

confidence: 99%

“…The diffusion phenomena occurring in chalcopyrite thin-film structures have been explored experimentally by measuring concentration profiles with methods such as secondary-ion mass spectroscopy (SIMS), [5][6][7] Auger electron spectroscopy (AES), 8 radioactive tracer technique (RTT), [9][10][11] and nuclear magnetic resonance (NMR). 12 However, extracting quantitative measures regarding self-diffusion from the experiments is not straightforward, and the studies can at most raise speculations of the dominant self-diffusion mechanisms in CIS: copper and indium diffusion have mostly been attributed to a vacancy-driven mechanism, 5,6,8,13 while selenium-related evidence is pointing towards an interstitial mechanism.…”

Section: Introductionmentioning

confidence: 99%

“…12 However, extracting quantitative measures regarding self-diffusion from the experiments is not straightforward, and the studies can at most raise speculations of the dominant self-diffusion mechanisms in CIS: copper and indium diffusion have mostly been attributed to a vacancy-driven mechanism, 5,6,8,13 while selenium-related evidence is pointing towards an interstitial mechanism. 9 Results should always be interpreted taking into account the limitations imposed by the methodology used.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Mass transport in CuInSe2 from first principles

Oikkonen

Ganchenkova

Seitsonen

et al. 2013

Journal of Applied Physics

View full text Add to dashboard Cite

The wide scatter in experimental results has not allowed drawing solid conclusions on selfdiffusion in the chalcopyrite CuInSe2 (CIS). In this work, the defect-assisted mass transport mechanisms operating in CIS are clarified using first-principles calculations. We present how the stoichiometry of the material and temperature affect the dominant diffusion mechanisms. The most mobile species in CIS is shown to be copper, whose migration proceeds either via copper vacancies or interstitials. Both of these mass-mediating agents exist in the material abundantly and face rather low migration barriers (1.09 and 0.20 eV, respectively). Depending on chemical conditions, selenium mass transport relies either solely on selenium dumbbells, which diffuse with a barrier of 0.24 eV, or also on selenium vacancies whose diffusion is hindered by a migration barrier of 2.19 eV. Surprisingly, indium plays no role in long-range mass transport in CIS; instead, indium vacancies and interstitials participate in mechanisms that promote the formation of antisites on the cation sublattice. Our results help to understand how compositional inhomogeneities arise in CIS. The wide scatter in experimental results has not allowed drawing solid conclusions on self-diffusion in the chalcopyrite CuInSe 2 (CIS). In this work, the defect-assisted mass transport mechanisms operating in CIS are clarified using first-principles calculations. We present how the stoichiometry of the material and temperature affect the dominant diffusion mechanisms. The most mobile species in CIS is shown to be copper, whose migration proceeds either via copper vacancies or interstitials. Both of these mass-mediating agents exist in the material abundantly and face rather low migration barriers (1.09 and 0.20 eV, respectively). Depending on chemical conditions, selenium mass transport relies either solely on selenium dumbbells, which diffuse with a barrier of 0.24 eV, or also on selenium vacancies whose diffusion is hindered by a migration barrier of 2.19 eV. Surprisingly, indium plays no role in long-range mass transport in CIS; instead, indium vacancies and interstitials participate in mechanisms that promote the formation of antisites on the cation sublattice. Our results help to understand how compositional inhomogeneities arise in CIS. V C 2013 American Institute of Physics. [http://dx

show abstract

References

2011

Chalcogenide Photovoltaics

View full text Add to dashboard Cite

Diffusion of indium and gallium in Cu(In,Ga)Se2 thin film solar cells

Cited by 120 publications

References 15 publications

Voids and compositional inhomogeneities in Cu(In,Ga)Se₂ thin films: evolution during growth and impact on solar cell performance

Voids and compositional inhomogeneities in Cu(In,Ga)Se₂ thin films: evolution during growth and impact on solar cell performance

Mass transport in CuInSe2 from first principles

References

Contact Info

Product

Resources

About

Diffusion of indium and gallium in Cu(In,Ga)Se2 thin film solar cells

Cited by 120 publications

References 15 publications

Voids and compositional inhomogeneities in Cu(In,Ga)Se2 thin films: evolution during growth and impact on solar cell performance

Voids and compositional inhomogeneities in Cu(In,Ga)Se2 thin films: evolution during growth and impact on solar cell performance

Mass transport in CuInSe2 from first principles

References

Contact Info

Product

Resources

About

Voids and compositional inhomogeneities in Cu(In,Ga)Se₂ thin films: evolution during growth and impact on solar cell performance

Voids and compositional inhomogeneities in Cu(In,Ga)Se₂ thin films: evolution during growth and impact on solar cell performance