چكيده به لاتين
Silicon nanowire solar cells are promising alternatives for expensive conventional bulk solar cells due to their unique light trapping properties and easy growth processes. Here we represent optical and electrical characteristics of a silicon asymmetric based nanowire solar cell with zigzag architecture arrays, and compare its performance with symmetric and asymmetric nanowire solar cells. We describe the strong optical absorption of our proposed design by finite-difference time domain simulations. Zigzag arrays show 15% enhancement in short current density, even in different angles of incident light, compared to cylindrical nanowires. This improved performance is due to efficient light confinement of zigzag nanowire arrays by increasing light trapping path for waves that are trapped inside the nanowires and conducting the waves that located in free space into the nanowires and substrate.
By optimizing the junction depth and dopant concentration and applying proper junction geometry, it is possible to extremely enhance the conversion efficiency of nanowire solar cells. Results for a non-optimal radial (p-n) zigzag nanowire solar cell, show 6.9% efficiency which is 10% higher than an asymmetric nanowire solar cell, in similar conditions. But, by adding an intrinsic interlayer to the junction, which results in reduction of surface recombination between p and n type semiconductors and improving junction performance, the efficiency increases to 7.3% and 7.8% for axial and radial (p-i-n) zigzag array nanowire solar cells, respectively. In addition, GaAs and InP zigzag array nanowire solar cells performances were represented. The axial p-i-n GaAs cell shows 17.3% conversion efficiency under 1sun illumination, which is one of the highest records for today’s nanowire solar cell technologies.
