Femtosecond Laser Drilling on Hard And Brittle Materials This article reviews femtosecond laser processing strategies for fabricating micro-holes in brittle materials such as silicon, silicon carbide, sapphire, and diamond. It compares drilling methods, auxiliary techniques, and the effects of different laser parameters on micro-hole quality. Despite significant progress, challenges such as ablation mechanisms, quality control, and large-scale fabrication remain, pointing to future development in hybrid techniques and beam shaping technologies.