TY  - JOUR
AU  - Smeets, Michael
AU  - Smirnov, Vladimir
AU  - Meier, Matthias
AU  - Bittkau, Karsten
AU  - Carius, Reinhard
AU  - Rau, Uwe
AU  - Paetzold, Ulrich W.
TI  - On the geometry of plasmonic reflection grating back contacts for light trapping in prototype amorphous silicon thin-film solar cells
JO  - Journal of photonics for energy
VL  - 5
IS  - 1
SN  - 1947-7988
CY  - Bellingham Wash.
PB  - SPIE
M1  - FZJ-2014-06164
SP  - 057004
PY  - 2015
AB  - We experimentally investigate the light-trapping effect of plasmonic reflection grating back contacts in prototype hydrogenated amorphous silicon thin-film solar cells in substrate configuration. These back contacts consist of periodically arranged Ag nanostructures on flat Ag reflectors. We vary the period, unit cell, and width of the nanostructures to identify design strategies for optimized light trapping. First, a general correlation between the reduction of the period of the nanostructures down to 550 nm and an increase of the absorptance, as well as external quantum efficiency is found for various unit cells formed by nanostructures. Second, increasing the width of the nanostructures from 200 to 350 nm, an enhanced light-trapping effect of the thin-film solar cells is found independent of the period. As a result, we identify a design for improved light trapping for the given solar cell parameters within the considered variations. It consists of thin-film solar cells applying a combination of a period of 600 nm and a structure width of 350 nm. The implementation of back contacts with this configuration yields enhanced power conversion efficiency as compared to reference solar cells processed on conventionally used randomly textured substrates. In detail, the enhancement of the short-circuit current density from initially 14.7 to initially 15.6  mA/cm2 improves the power conversion efficiency from 9.1 to 9.3%.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000359851000001
DO  - DOI:10.1117/1.JPE.5.057004
UR  - https://juser.fz-juelich.de/record/172720
ER  -