Cu depletion at the CuInSe2 surface

Liao, Dongxiang; Rockett, Angus

doi:10.1063/1.1570516

Cited by 107 publications

(100 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…D) was explained in the past by the formation of an ordered defect compound (ODC) layer 46,47 or by surface reconstruction. 51,52 While according to first-principles calculations the ODC can be considered as periodic repetition of the charge compensated (2 V Cu À þ In Cu 2þ ) defect complex (as described in Ref. 53), it was also suggested by theory that the surface reconstruction is based on the formation of the energetically most favorable metal-terminated (112) and selenium-terminated ( 112) CIGSe surfaces stabilized through V Cu À and subsurface In Cu 2þ defects, respectively.…”

Section: E Binding Energy Shiftmentioning

confidence: 99%

Na incorporation into Cu(In,Ga)Se2 thin-film solar cell absorbers deposited on polyimide: Impact on the chemical and electronic surface structure

Song

Caballero

Félix

et al. 2012

Journal of Applied Physics

View full text Add to dashboard Cite

The following article appeared in Journal of Applied Physics 111.3 (2012): 034903 and may be found at http://scitation.aip.org/content/aip/journal/jap/111/3/10.1063/1.3679604Na has deliberately been incorporated into Cu(In,Ga)Se2 (CIGSe) chalcopyrite thin-film solar cell absorbers deposited on Mo-coated polyimide flexible substrates by adding differently thick layers of NaF in-between CIGSe absorber and Mo back contact. The impact of Na on the chemical and electronic surface structure of CIGSe absorbers with various Cu-contents deposited at comparatively low temperature (420 C) has been studied using x-ray photoelectron and x-ray excited Auger electron spectroscopy. We observe a higher Na surface content for the Cu-richer CIGSe samples and can distinguish between two different chemical Na environments, best described as selenide-like and oxidized Na species, respectively. Furthermore, we find a Cu-poor surface composition of the CIGSe samples independent of Na content and - for very high Na contents - indications for the formation of a (Cu,Na)-(In,Ga)-Se like compound. With increasing Na surface content, also a shift of the photoemission lines to lower binding energies could be identified, which we interpret as a reduction of the downward band bending toward the CIGSe surface explained by the Na-induced elimination of In Cu defects.X.S., R.F., D.G., R.G.W., and M.B. are grateful to the Helmholtz-Association for financial support (VH-NG-423). R.F. also acknowledges the support by the German Academic Exchange Agency (DAAD; 331 4 04 002)

show abstract

Section: E Binding Energy Shiftmentioning

confidence: 99%

Na incorporation into Cu(In,Ga)Se2 thin-film solar cell absorbers deposited on polyimide: Impact on the chemical and electronic surface structure

Song

Caballero

Félix

et al. 2012

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…Only the very first data points of the copper concentration in the SNMS depth profiles show deviations to lower values for all samples, which is most probably related to the copper depletion of chalcopyrite thin film surfaces with respect to their bulk composition. As mentioned above, it was found that this surface copper depletion is restricted to the top atomic layer and is caused by a defect-induced surface reconstruction, [25][26][27] which is not accessible by AXES. 20 The reduced copper concentration in the SNMS data could be a consequence of this.…”

Section: Sample Preparationmentioning

confidence: 99%

Gallium gradients in chalcopyrite thin films: Depth profile analyses of films grown at different temperatures

Mönig

Kaufmann

Fischer

et al. 2011

Journal of Applied Physics

View full text Add to dashboard Cite

Cu(In,Ga)Se 2 films are used as absorber layers in chalcopyrite thin film solar cells. As the gallium concentration in the absorber can be used to control the band gap, there have been many efforts to vary the gallium concentration in depth to gain an optimum balance of light absorption, carrier collection, and recombination at different depths of the absorber film, leading to improved quantum efficiency. In this study, we investigate the effect of the maximum substrate temperature during film growth on the depth dependent gallium concentration. For the in-depth gallium concentration analyses, we use two techniques, covering complementary depth ranges. Angle dependent soft x-ray emission spectroscopy provides access to information depths between 20 and 470 nm, which covers the depth range of the space charge region, where most of the photoexcited carriers are generated. Therefore, this depth range is of particular interest. To complement this investigation we use secondary neutral mass spectrometry, which destructively probes the whole thickness of the absorber (%2 lm). The two methods show increasingly pronounced gallium and indium gradients with decreasing maximum substrate temperature. The probing of the complementary depth ranges of the absorbers gives a consistent picture of the in-depth gallium distribution, which provides a solid basis for a comprehensive discussion about the effect of a reduced substrate temperature on the formation of gallium gradients in Cu(In,Ga)Se 2 and the device performance of the corresponding reference solar cells.

show abstract

“…Thus, Cd doping at the CIGSe/CdS grain boundaries and conductivity inversion of the absorber from p-to n-types is inevitable. Other significant observations such as Se-S exchange within CdS-CIGSe, Cd diffusion in CIGSe, Cu-Cd interdiffusion at CdS/CIGSe interface, alkali-oxygen (Na-O) impurity accumulations at the interface, Cu 2−x Se secondary phase, and Cd-Se formations are also reported [36][37][38][39]. However, the CdS/CIGSe junction interface study is still a debatable research topic which needs further clarifications.…”

Section: Cise/cigse Materials Properties and Device Structurementioning

confidence: 99%

A short review on the advancements in electroplating of CuInGaSe2 thin films

Chandran

Panda

Mallik

2018

Mater Renew Sustain Energy

View full text Add to dashboard Cite

Thin-film solar cell devices based on copper indium gallium diselenide (CIGSe) chalcogenide materials fabricated by vacuum-based deposition techniques have already achieved lab scale efficiency beyond 21%. For industrial-scale applications, non-vacuum deposition technique such as electrodeposition and screen printing is considered to be suitable approaches for reducing the device fabrication cost. Moreover, electrodeposition has the potential to prepare large area thin films as it requires cheap raw material sources and equipment capital. Hence, it is imperative to understand the current status and advancements in the electroplating techniques of the CIGSe thin films. This article reviews on the experimental advances in electroplating of ternary CuInSe 2 and quaternary CIGSe. Various approaches in electrodeposition, influential experimental parameters, and the deposition mechanisms which are related to the final cell efficiency are discussed in detail.

show abstract

Cu depletion at the CuInSe2 surface

Cited by 107 publications

References 13 publications

Na incorporation into Cu(In,Ga)Se2 thin-film solar cell absorbers deposited on polyimide: Impact on the chemical and electronic surface structure

Na incorporation into Cu(In,Ga)Se2 thin-film solar cell absorbers deposited on polyimide: Impact on the chemical and electronic surface structure

Gallium gradients in chalcopyrite thin films: Depth profile analyses of films grown at different temperatures

A short review on the advancements in electroplating of CuInGaSe2 thin films

Contact Info

Product

Resources

About