Magnetron sputtering growth of AZO/ZnO/Zn(O,S) multilayers for Cu2ZnSnS4 thin film solar cells: Material and device characterization için kapak resmi
Magnetron sputtering growth of AZO/ZnO/Zn(O,S) multilayers for Cu2ZnSnS4 thin film solar cells: Material and device characterization
Başlık:
Magnetron sputtering growth of AZO/ZnO/Zn(O,S) multilayers for Cu2ZnSnS4 thin film solar cells: Material and device characterization
Yazar:
Köseoğlu, Fulya, author.
Yazar Ek Girişi:
Fiziksel Tanımlama:
xv, 151 leaves: illustrarions, charts;+ 1 computer laser optical disc.
Özet:
Cu2ZnSnS4 (CZTS) absorber layer attracts so much attention in photovoltaic industry since it contains earth abundant, low cost and non-toxic elements contrary to other chalcogenide based solar cells such as CuInGa(S,Se)2 (CIGS) and CdTe. Although, CZTS studies have been newly started, recently 9.4 % efficiency has been achieved. In the present thesis, all layers used in the CZTS device structure were investigated using energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), scanning electron microscopy (SEM), spectrophotometry and Raman spectroscopy. For CZTS absorber layer, CZTS films based on a stacked precursor (Cu/Sn/Zn/Cu) were prepared. The effect of sulfurization time and the thickness of top and bottom Cu layer in precursors on the properties of CZTS thin films were investigated. We addressed the importance of Cu layer thickness adjacent to Sn to avoid developing detrimental phases and to get complete formation of kesterite CZTS absorber layer. We also addressed the importance of sulfurization time to restrict the Sn and Zn losses, formation of oxides such as SnO2 and ZnO, formation of MoS2 and voids between Mo/CZTS interface. Effect of the sulfur concentration on the properties of Zn(O,S) thin films were investigated. We showed that key parameters such as energy gap and crystal structure of the Zn(O,S) thin films can be tuned by changing the sulfur concentrations of the films. We succeed substitute conventionally used CdS buffer layer with environmentally friendly alternative Zn(O,S) buffer layer in CZTS solar cells. Effect of substrate position and rotation speed during the deposition of AZO thin films were investigated. We addressed that stress on the films can be significantly reduced by off-center deposition and rotating the sample holder during the deposition. In this way, high transmission in the visible range and metal like resistivity were achieved simultaneously at room temperature. We observed strong dependence of device performances on both sulfurization time and the thickness of Cu layer adjacent to Sn in CZTS absorber. The best device was based on CZTS films sulfurized for 30 minutes and having thicker Cu layer adjacent to Sn layer in precursors.
Yazar Ek Girişi:
Tek Biçim Eser Adı:
Thesis (Doctoral)--İzmir Institute of Technology: Material Science and Engineering.

İzmir Institute of Technology: Material Science and Engineering--Thesis (Doctoral).
Elektronik Erişim:
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