Electron traps in Cu(In,Ga)Se2 absorbers of thin film solar cells studied by junction capacitance techniques

• Autorzy: Igalson M. , Zabierowski P.
• Języki publikacji: EN

Abstrakty

EN

The results of steady state and transient capacitance spectrocsopy for ZnO/CdS/Cu(In,Ga)Se2 solar cells are presented. A minority carrier signal from the interface region of absorber has been investigated using Laplace-DLTS. Contributions belonging to three discrete electron traps with thermal emission rates distorted by electric field - assisted tunnelling have been identified and assigned to InCu antisite defect. Support for these conclusions has been also provided by admittance spectroscopy of samples in various metastable states created by prolonged exposition to light, voltage bias or elevated temperature. Two other deep electron traps have been revealed by the use of DLTS injection. One of them, tentatively assigned to the VSe defect, is involved in the metastable phenomena observed in Cu(In,Ga)Se2 - based solar cells. Judging from the high value of capture cross section for carriers of both signs we conclude that it might be a dominating recombination centre in these devices.

Słowa kluczowe

EN

solar cells; Cu(In,Ga)Se2; defect levels; DLTS; admittance spectroscopy

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2003
• Tom: Vol. 11, No. 4
• Strony: 261--267
• Opis fizyczny: Bibliogr. 24 poz., rys.

Twórcy

autor

Igalson M.

• Faculty of Physics, Warsaw University of Technology, 75 Koszykowa Str., 00-662 Warszawa, Poland

autor

Zabierowski P.

• Faculty of Physics, Warsaw University of Technology, 75 Koszykowa Str., 00-662 Warszawa, Poland

Bibliografia

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