High-Aspect-Ratio Silicon Nanostructures on N-type Silicon Wafer Using Metal-Assisted Chemical Etching (MACE) Technique

In this paper, silicon nanowires formation on N-type crystalline silicon wafer is studied. Metal-assisted chemical etching (MACE) technique is used in this study because it’s low cost but can produce a high-aspect-ratio of silicon nanowires. High-aspect-ratio silicon nanostructures have been proved as an effective texture for light trapping on silicon solar cells surfaces. The photons from incident light can be trap on the silicon nanowires and then being absorb into the cells which resulting high efficiency silicon solar cells. Traditionally, MACE works by creating a holes using metal catalyst such as Ag or Au in order to reduce of the etchant. The hydrofluoric acid (HF) and hydrogen peroxide (H
2
O
2
) are function to etched the metal native oxide thus create a pores or nanowires formation. Roughness parameters of silicon nanowires was investigate in order to see the texture of silicon nanowires is rough enough to trap more photons on silicon wafer surfaces. Hence, roughness parameters are very important for texturing silicon wafer surfaces. In this study, root mean square (RMS) is used as an indicators for which acquired from the line profiles. Results from the roughness parameters shown a good compatibility.