ABSTRACT
Metal-assisted chemical etching (MACE) is a top-down fabrication method based on wet chemical etching and has been successfully used for preparing a variety of vertical silicon nanostructures. This chapter describes the MACE process in terms of electroless metal deposition (EMD), silicon etching, and mass transport. For instance, vertical silicon nanostructures have been successfully combined with various energy conversion and storage materials, leading to many practical applications such as solar cells, photoelectrochemical cells (PECs), and batteries. The chapter describes the diverse applications of vertical silicon nanostructures fabricated by MACE process in comparison with those prepared by vapor-liquid-solid (VLS) growth or gas-based dry etching. Compared with those prepared with VLS growth, vertical silicon nanowire arrays produced using MACE offer the equivalent electrical properties and the robust nanowire structures as the integral parts of silicon substrates. The chapter discusses the influence of specific noble metal catalyst, silicon crystal structure, and etching solution on the geometry and morphology of the resulting vertical silicon nanostructures.
