Quantum dot solar cells using 2-dimensional array of 6.4-nm-diameter silicon nanodisks fabricated using bio-templates and neutral beam etching

摘要

Quantum dot solar cells consisting of a sub-10-nm highly ordered and dense 2-dimensional (2D) array of Si nanodisks (Si-NDs) as a quantum dot superlattice with a SiC interlayer are achieved. The Si-NDs are fabricated with an original top-down process involving a 2D array of bio-templates with a 4.5-nm-diameter iron core and damage-free neutral beam etching (Si-ND diameter: 6.4 nm). The Si-ND array has a high optical absorption coefficient due to miniband formation. As a result, the cells achieve open-circuit voltage of 0.556 V, short-circuit current density of 31.3mA/cm~2, a 72% fill factor, and 12.6% conversion efficiency.