ng target adopts the static electromagnetic field, which is curvilinear, while the plane target and cylindrical target adopt the uniform electric field and logarithm electric field respectively. Under effect of the electric field, the electron will collide with the argon atom in the process of accelerating flying to the substrate. When the electron has enough energy (abou 30ev), Ar+ will be ionized and the electron will be produced and fly to the substrate; under effect of the electric field, Ar