Title :
A new thin-film CuGaSe2/Cu(In,Ga)Se2 bifacial, tandem solar cell with both junctions formed simultaneously
Author :
Young, David L. ; Abushama, Jehad ; Noufi, Rommel ; Li, Xiaonan ; Keane, James ; Gessert, Timothy A. ; Ward, J. Scott ; Contreras, Miguel ; Symko-Davies, Martha ; Coutts, Timothy J.
Author_Institution :
Nat. Renewable Energy Lab., Golden, CO, USA
Abstract :
Thin films of CuGaSe2 and Cu(In,Ga)Se2 were evaporated by the 3-stage process onto opposite sides of a single piece of soda-lime glass, coated bifacially with an n+-TCO. Junctions were formed simultaneously with each of the p-type absorbers by depositing thin films of n-CdS via chemical bath deposition (CBD) at 60°C. The resulting four-terminal device is a nonmechanically stacked, two-junction tandem. The unique growth sequence protects the temperature-sensitive p/n junctions. The initial device (η = 3.7%, Voc = 1.1 V [AM1.5]) suffered from low quantum efficiencies. Initial results are also presented from experiments with variations in growth sequence and back reflectors.
Keywords :
copper compounds; gallium compounds; indium compounds; liquid phase deposited coatings; semiconductor device measurement; solar cells; ternary semiconductors; 1.1 V; 3-stage process; 60 degC; CuGaSe2-Cu(InGa)Se2; Na2OCaOSiO2; chemical bath deposition; n+-TCO; soda-lime glass; temperature-sensitive p/n junctions; thin-film CuGaSe2/Cu(In,Ga)Se2 bifacial tandem solar cell; Chemicals; Contacts; Glass; Photovoltaic cells; Prototypes; Scanning electron microscopy; Substrates; Temperature measurement; Transistors; Zinc oxide;
Conference_Titel :
Photovoltaic Specialists Conference, 2002. Conference Record of the Twenty-Ninth IEEE
Print_ISBN :
0-7803-7471-1
DOI :
10.1109/PVSC.2002.1190638
