Biswas Rana, Xu Chun
Ames Laboratory, Dept. of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
Opt Express. 2011 Jul 4;19 Suppl 4:A664-72. doi: 10.1364/OE.19.00A664.
We develop a periodically patterned conformal photonic-plasmonic crystal based solar architecture for a nano-crystalline silicon solar cell, through rigorous scattering matrix simulations. The solar cell architecture has a periodic array of tapered silver nano-pillars as the back-reflector coupled with a conformal periodic structure at the top of the cell. The absorption and maximal current, averaged over the entire range of wavelengths, for this solar cell architecture is at the semi-classical 4n(2) limit over a range of common thicknesses (500-1500 nm) and slightly above the 4n(2) limit for a 500 nm nc-Si cell. The absorption exceeds the 4n(2) limit, corrected for reflection loss at the top surface. The photonic crystal cell current is enhanced over the flat Ag back-reflector by 60%, for a thick 1000 nm nc-Si layer, where predicted currents exceed 31 mA/cm(2). The conformal structure at the top surface focuses light within the absorber layer. There is plasmonic concentration of light, with intensity enhancements exceeding 7, near the back reflector that substantially enhances absorption.
通过严格的散射矩阵模拟，我们为纳米晶硅太阳能电池开发了一种基于周期性图案化共形光子 - 等离子体晶体的太阳能结构。该太阳能电池结构具有作为背反射器的锥形银纳米柱的周期性阵列，并在电池顶部耦合有共形周期性结构。对于这种太阳能电池结构，在整个波长范围内平均的吸收和最大电流，在一系列常见厚度（500 - 1500纳米）下处于半经典的4n²极限，对于500纳米的纳米晶硅电池略高于4n²极限。吸收超过了考虑顶表面反射损失校正后的4n²极限。对于厚1000纳米的纳米晶硅层，光子晶体电池电流比平坦的银背反射器增强了60%，预测电流超过31 mA/cm²。顶表面的共形结构将光聚焦在吸收层内。在背反射器附近存在光的等离子体集中，强度增强超过7，这大大增强了吸收。
