The invention discloses a method for forming a metallic electrode (15) of a semiconductor device (10). The method comprises obtaining surface shape data of the surface part (11c) of a semiconductor substrate (11), and deforming the semiconductor substrate (11) with the deformation devices (24, 24a) based on the data to make the distance between a cutting plane (P) and a surface part (11c) fit into a cutting precision scope required. During deformation of the semiconductor substrate (11), a plurality of actuator (24 a) serve as deformation devices (24, 24a). The distance between actuator (24 a) is large than half of the wavelength of the distributive spatial frequency of the thickness of the semiconductor substrate (11) and is smaller or equals to the wavelength.