Fabrication of high-performance ordered radial junction silicon nanopencil solar cells by fine-tuning surface carrier recombination and structure morphology

Highlights: • Silicon nanopencils (SiNPs) were fabricated by colloidal lithography and ICP-RIE process. • The control of SiNPs morphology increased the effective junction areas. • Optimized SiNPs solar cell device obtain a 14.3% efficiency. -- Abstract: A high-efficiency (14.3%) solar cell using silicon nanopencils (SiNPs) was achieved by controlling surface carrier recombination and nanostructure morphology. Radial p-n junction nanopencils have several advantageous features that derive from their asymmetric structure, which enables excellent broad-band absorption and light trapping. The surface carrier recombination problem caused by plasma etching was solved using a chemical polish etching (CPE) method. The control of CPE treatment and SiNP morphology can reduce the surface recombination and increases the effective junction area. And bulk recombination was minimized by reducing the wafer thickness. These techniques have the potential to achieve low-cost and high-efficiency photovoltaic cells.