Influence of the donor doping density in CdS and Zn(O,S) buffer layers on the external quantum efficiency of Cu(In,Ga)Se2 thin film solar cell

Influence of the donor doping density in CdS and Zn(O,S) buffer layers on the external quantum efficiency of Cu(In,Ga)Se2 thin film solar cell

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
  
© 2015 by IJETT Journal
Volume-28 Number-6
Year of Publication : 2015
Authors : Alain Kassine EHEMBA, Moustapha DIENG, Demba DIALLO, Gerome SAMBOU
DOI :  10.14445/22315381/IJETT-V28P253

Citation 

Alain Kassine EHEMBA, Moustapha DIENG, Demba DIALLO, Gerome SAMBOU"Influence of the donor doping density in CdS and Zn(O,S) buffer layers on the external quantum efficiency of Cu(In,Ga)Se2 thin film solar cell", International Journal of Engineering Trends and Technology (IJETT), V28(6),280-286 October 2015. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group

Abstract
In this paper, we study the influence of the donor doping density of the buffer layer on external quantum efficiency EQE. We simulate a Cu(In,Ga)Se2 thi film solar cell using the AMPS. We use two types of buffer layer: the Zn(O,S) and the CdS. These layers are doped N with various doping densities going from 1015cm-3 to 1020cm-3.The variation of external quantum efficiency shows us that for the doping densities going from 1015cm-3 to 1017cm-3, the Zn(O,S) buffer layer gives more powerful properties than those of the CdS buffer layer. For the doping densities higher than 1017cm-3, the Zn(O,S) and CdS layers give properties which make them competing. They present maximum absorption areas extended on broad wavelength ranges. We note an EQE which can reach 100% for the cells with the Zn(O,S) buffer layer and 98.6% for the cells with the CdS buffer layer. Then the Zn(O, S) buffer layer gives better quantum efficiency according to its doping density even if the CdS buffer layer is more known.

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Keywords
buffer layer, donor density, CdS, Zn(O,S), Cu(In,Ga)Se2, external quantum efficiency EQE.