Capacitor structure, semiconductor device and capacitor structure preparation method

The invention discloses a capacitor structure, a semiconductor device and a capacitor structure preparation method. A supporting structure is arranged on the outer side wall of a lower electrode of acolumnar structure; the supporting structure comprises a top supporting structure for supporting the upper area of the lower electrode; the top supporting structure at least comprises a first supporting layer and a second supporting layer made of a material different from that of the first supporting layer. The lower surface of the first supporting layer is arranged to be in contact with the uppersurface of the second supporting layer, the contact interface of the first supporting layer and the second supporting layer is lower than the top of the lower electrode, and the upper surface of thefirst supporting layer is higher than the top of the lower electrode; a capacitor dielectric layer covering the lower electrode and the support structure and an upper electrode covering the capacitordielectric layer are formed,