Nanoscale imaging of solar cells using Kelvin probe force microscopy

In the search for renewable energy, solar cells have become the prevailing alternative; however, the main drawback to consider in solar cells is their limited efficiency. To identify the causes of limiting factors, we investigated the fundamental interaction between photons and electrons of polysilicon solar cells at the nanoscale using a Kelvin probe force microscopy (KPFM) technique. With this technique, we imaged nanoscale surface potential of polycrystalline silicon solar cells. In this presentation, we discuss how influential the defects at grain boundaries affect electrical properties of solar cells. To improve photo responses, we employed nanophotonic materials such as quantum dots and plasmonic nanostructures atop polycrystalline solar cells. We also present how these nanomaterials enhance surface potential of solar cells at the nanoscale using the same measurement technique. Lastly, we discuss the potential and limitations of a KPFM technique.