Controlled fabrication of upright and inverted pyramid arrays of silicon via the interaction of copper ions and oxidants in hydrofluoric acid

Recent advances in chemical etching of silicon have allowed its widespread use in the fabrication of microelectronic devices and energy converters, in which shaped silicon exhibits outstanding properties and functions. The texturing process used to fabricate light-trapping structures on silicon surfaces is an indispensable step in preparing solar cells. Here, this manuscript describes the use of a one-step wet chemical etching method with copper as a catalyst to manufacture different structures, including inverted pyramid structures and upright pyramid structures, on silicon surfaces, which can be easily controlled by varying the solution composition and etching time. Moreover, this manuscript demonstrates an exciting method for fabricating random inverted pyramid and random upright pyramid arrays of silicon. The findings provide important contributions that can help improve the fabrication methods for silicon-based solar cell devices and optimize the light trapping structure on the cell surface.