Semiconductor capacitor structure and formation method thereof

The invention provides a semiconductor capacitor structure. The semiconductor capacitor structure comprises a semiconductor substrate, a first polysilicon layer positioned on the surface of the semiconductor substrate, a first medium layer which is positioned on the surface of the first polysilicon layer and covered on the side wall of the first polysilicon layer, a second polysilicon layer which is positioned on the surface of the first polysilicon layer and covered on the side wall of the first polysilicon layer, and a through hole which penetrates through the second polysilicon layer and the first medium layer and is used for exposing the first polysilicon layer. Correspondingly, the invention also provides a formation method of the semiconductor capacitor structure. By the semiconductor capacitor structure and the formation method thereof, a polysilicon longitudinal beam cannot be formed, and a process flow is simplified.