We report on the fabrication and measurement of ultrathin a-Si solar cells with plasmonic back contacts composed of nanopattern dendritic/shrub-like Ag nanostructures that exhibit enhanced short circuit densities compared cells with flat back contacts. The morphology of the Ag nanostructure can be well controlled by the reaction time. When the proposed structure was used in the solar cell. The back-reflector of solar cell can be well designed by various Ag nanostructures and periods. A one-dimension shrub-like Ag nanostructure with spacing of 600 nm, exhibited a 14 % increase in short-circuit current density and a 20% increase in energy conversion efficiency are observed. This study indicates that the dendritic/shrub-like Ag nanostructure can be applied as a enhancing conversion configuration for ultrathin a-Si solar cells.
Various silver nanostructures, semi-ball, jungle, and dendritic, are demonstrated by an
electrical deposition process. The formation of silver nanostructures with various morphologies is
studied by the mechanism of the diffusion limited aggregation (DLA) model. A array pattern of silver
nanostructures can be obtained when the conductive substrate was used in a uniform electrical filed. A
thickness 500 nm of Alq3 thin-film was covered on the silver nanostructure by thermal evaporation
method. The strongest intensity of Alq3 green emission was observed when the pattern-array dendritic
silver nanostructure was covered by Alq3. It can be explained with the plasmonic coupling due to the
Alq3 and dendritic nanostructure. The result can help us to further application the patterned-array
silver dendritic nanostructure for advanced opto-electronic device.