Temperature dependence of photocapacitance spectrum of CIGS thin-film solar cell

Sakurai, Takayasu; Uehigashi, Hideyuki; Islam, Muhammad Monirul; Miyazaki, Takashi; Ishizuka, Shogo; Sakurai, Katsutoshi; Yamada, A.; Matsubara, Koji; Niki, Shigeru; Akimoto, Katsuhiro

doi:10.1016/j.tsf.2008.11.051

Cited by 34 publications

(19 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The large A and J 0 values observed from CGS solar cells are attributable to a larger carrier recombination probability than that for CIGS solar cells due to the absence of a Ga gradient that is believed to have the effect of repelling minority carriers (the so‐called back surface field effect). The presence of a deep defect level at 0.8 eV above the valence band maximum, which is independent of the [Ga]/[In] composition ratio in CIGS, has also been regarded to act as a possible recombination center for CGS solar cells . Nevertheless, CGS solar cell efficiencies exceeding 10% were demonstrated in this study.…”

Section: Resultsmentioning

confidence: 72%

Structural tuning of wide-gap chalcopyrite CuGaSe₂ thin films and highly efficient solar cells: differences from narrow-gap Cu(In,Ga)Se₂

Ishizuka

Yamada

Fons

et al. 2014

Prog. Photovolt: Res. Appl.

View full text Add to dashboard Cite

Simultaneous realization of high values of open circuit voltage (V oc ), fill factor (FF), and energy conversion efficiency (η) in wide-gap CuGaSe 2 (CGS) solar cells has long been one of the most challenging issues in the realm of chalcopyrite photovoltaics. In this communication, structural tuning of CGS thin films by means of controlling the amount of Se flux used during CGS film growth and improvements in solar cell performance (V oc > 0.9 V, FF > 0.7, and η > 10%) are demonstrated. Systematic variations in CGS film properties with the Se flux and correlation with device properties are shown. The unique CGS thin-film growth kinetics, which are different from narrow-gap Cu(In,Ga)Se 2 , are also presented and discussed. This development of double digit efficiency for CGS solar cells opens a new frontier for the broad application of a new class of chalcopyrite-based devices.

show abstract

Section: Resultsmentioning

confidence: 72%

Structural tuning of wide-gap chalcopyrite CuGaSe₂ thin films and highly efficient solar cells: differences from narrow-gap Cu(In,Ga)Se₂

Ishizuka

Yamada

Fons

et al. 2014

Prog. Photovolt: Res. Appl.

View full text Add to dashboard Cite

show abstract

“…Existence of the deep-level defect around 0.8 eV above E v in CIGS has been reported previously. 30 It can be seen from the figure that intensity of the defect-signal is much higher in case of CZTS and CZTSSe-based solar cells. Urbach energy of E u $ 28 meV has been calculated for CIGS from band-tail region of the corresponding TPC signals.…”

mentioning

confidence: 88%

Determination of deep-level defects in Cu2ZnSn(S,Se)4 thin-films using photocapacitance method

Islam

Halim

Sakurai

et al. 2015

Applied Physics Letters

View full text Add to dashboard Cite

Deep-level defects were investigated in Cu2ZnSn(S,Se)4 and Cu2ZnSnS4 thin-films using transient photocapacitance (TPC) spectroscopy. A deep-defect, OH1 centered around 1.0 eV above the valance-band (EV) of Cu2ZnSnS4 has been identified at room temperature (RT). However, OH1-defect could be identified in Cu2ZnSn(S,Se)4 at low temperature only. Absence of OH1-defect in Cu2ZnSn(S,Se)4 at RT explains its better performance comparing to Cu2ZnSnS4 solar-cell. A comparative study of the TPC spectra of the Cu(In,Ga)Se2 solar-cells was performed. Low intensity of defect-signal together with lower broadening of exponential band-tail in the TPC spectra were attributed to superior performance of Cu(In,Ga)Se2 solar-cells comparing to Cu2ZnSn(S,Se) counterpart.

show abstract

“…[13,14] The presence of point defects in the CIGSe absorber material might lead to the formation of recombination centers and limit the device efficiency. [28,29] In addition, deep-level transient spectroscopy probed at least two transition levels in the CIGSe absorber. Experimentally, point defects in CuInSe 2 (CISe), CuGaSe 2 (CGSe), and CIGSe have been studied using different techniques such as photoluminescence, [15][16][17][18][19][20][21] cathodoluminescence, [22][23][24] and optical absorption measurement.…”

Section: Introductionmentioning

confidence: 99%

Alkali Atoms Diffusion Mechanism in CuInSe₂ Explained by Kinetic Monte Carlo Simulations

Raghupathy

Kühne

Henkelman

et al. 2019

Advcd Theory and Sims

View full text Add to dashboard Cite

Adaptive kinetic Monte Carlo simulation (aKMC) is employed to study the dynamics and the diffusion of point defects in the CuInSe 2 lattice. The aKMC results show that lighter alkali atoms can diffuse into the CuInSe 2 grains, whereas the diffusion of heavier alkali atoms is limited to the Cu-poor region of the absorber. The key difference between the diffusion of lighter and heavier alkali elements is the energy barrier of the ion exchange between alkali interstitial atoms and Cu. For lighter alkali atoms like Na, the interstitial diffusion and the ion-exchange mechanism have comparable energy barriers. Therefore, Na interstitial atoms can diffuse into the grains and replace Cu atoms in the CuInSe 2 lattice. In contrast to Na, the ion-exchange mechanism occurs spontaneously for heavier alkali atoms like Rb and the further diffusion of these atoms depends on the availability of Cu vacancies. The outdiffusion of alkali substitutional atoms from the grains results in the formation of Cu vacancies which in turn increases the hole concentration in the absorber. In this respect, Na is more efficient than Rb due to the higher concentration of Na substitutional defects in the CuInSe 2 grains.

show abstract

Temperature dependence of photocapacitance spectrum of CIGS thin-film solar cell

Cited by 34 publications

References 19 publications

Structural tuning of wide-gap chalcopyrite CuGaSe₂ thin films and highly efficient solar cells: differences from narrow-gap Cu(In,Ga)Se₂

Structural tuning of wide-gap chalcopyrite CuGaSe₂ thin films and highly efficient solar cells: differences from narrow-gap Cu(In,Ga)Se₂

Determination of deep-level defects in Cu2ZnSn(S,Se)4 thin-films using photocapacitance method

Alkali Atoms Diffusion Mechanism in CuInSe₂ Explained by Kinetic Monte Carlo Simulations

Contact Info

Product

Resources

About

Temperature dependence of photocapacitance spectrum of CIGS thin-film solar cell

Cited by 34 publications

References 19 publications

Structural tuning of wide-gap chalcopyrite CuGaSe2 thin films and highly efficient solar cells: differences from narrow-gap Cu(In,Ga)Se2

Structural tuning of wide-gap chalcopyrite CuGaSe2 thin films and highly efficient solar cells: differences from narrow-gap Cu(In,Ga)Se2

Determination of deep-level defects in Cu2ZnSn(S,Se)4 thin-films using photocapacitance method

Alkali Atoms Diffusion Mechanism in CuInSe2 Explained by Kinetic Monte Carlo Simulations

Contact Info

Product

Resources

About

Structural tuning of wide-gap chalcopyrite CuGaSe₂ thin films and highly efficient solar cells: differences from narrow-gap Cu(In,Ga)Se₂

Structural tuning of wide-gap chalcopyrite CuGaSe₂ thin films and highly efficient solar cells: differences from narrow-gap Cu(In,Ga)Se₂

Alkali Atoms Diffusion Mechanism in CuInSe₂ Explained by Kinetic Monte Carlo Simulations