Nanowire arrays are promising structures for 3rd generation photovoltaics, due to their absorption enhancement over thin films and reduction in material usage. Having previously studied the absorption mechanism of silicon nanowire arrays suspended in air, we now extend the analysis to arrays on substrates. We find that the absorption mechanism continues to be dominated by one (or more) well coupled, well concentrated, resonant modes. Whilst the substrates reduce the strength of the resonances, they can simultaneously increase short wavelength absorption. The ultimate efficiency of the arrays remains significantly greater than that of silicon thin films and with a silicon substrate exceeds that of arrays suspended in air.
|Conference||Optical Nanostructures and Advanced Materials for Photovoltaics|
|Period||2/11/11 → 3/11/11|