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Title: Design and Simulation of the Bifacial III-V-Nanowire-on-Si Solar Cell
ABSTRACT Rigorous coupled wave analysis (RCWA) simulation was used to model the absorption in periodic arrays of GaAs(0.73)P(0.27) nanowires (NWs) on Si substrates dependent upon the diameter (D), length (L), and spacing (center-to-center distance, or pitch, P) of the NWs. Based on this study, two resonant arrangements for a top NW array sub-cell having the highest limiting short-circuit current densities (J_sc) were found to be close to D = 150 nm, P = 250 nm and D = 300 nm, P = 500 nm, both featuring the same packing density of 0.28. Even though a configuration with thinner NWs exhibited the highest J_sc = 19.46 mA/cm^2, the array with D = 350 nm and P = 500 nm provided current matching with the underlying Si sub-cell with J_sc = 18.59 mA/cm^2. Addition of a rear-side In(0.81)Ga(0.19)As nanowire array with D = 800 nm and P = 1000 nm was found to be suitable for current matching with the front NW sub-cell and middle Si. However, with thinner and sparser In(0.81)Ga(0.19)As NWs with D = 700 nm and P = 1000 nm, the J_scof the bottom sub-cell was increased from 17.35 mA/cm^2 to 18.76 mA/cm^2 using a planar metallic back surface reflector, thus achieving a current matching with the top and middle cells.  more » « less
Award ID(s):
1665086
PAR ID:
10092177
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
MRS Advances
ISSN:
2059-8521
Page Range / eLocation ID:
1 to 8
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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