Metal-assisted homogeneous etching of single crystal silicon: A novel approach to obtain an ultra-thin silicon wafer

► Homogeneous etching of silicon is achieved, it offers a simple route to get ultra-thin silicon wafer with thickness below 50 μm. ► The surface of the ultra-thin silicon wafer is smooth at the nanometer scale across a large wafer area, and its surface roughness is around 10 nm. ► Any thickness of silicon wafer within 30-180 μm can be obtained by this method.