Capacitor structure, semiconductor device and capacitor structure preparation method

Abstract

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, so the electric leakage rate can be reduced while the extending height of the lower electrode in the vertical direction is met, the supporting structure at the position needing to be reserved is prevented from being damaged in the patterning process of the top supporting structure of the lower electrode, and the stability of the lower electrode and the performance of the capacitor structure can be effectively improved.

Description

technical field [0001] The present application relates to the field of semiconductor technology, and in particular to a capacitance structure, a semiconductor device and a method for preparing the capacitance structure. Background technique [0002] Capacitors, as a semiconductor storage device, are constantly being miniaturized with the progress and requirements of the manufacturing process in the prior art. In order to ensure the storage capacity of the capacitor on the basis of miniaturization, it is usually necessary to extend the electrode in the vertical direction to the substrate, such as setting the lower electrode with a columnar structure, and setting the lower electrode extended in the vertical direction may easily cause the bottom electrode to tilt or bending. Therefore, it is necessary to provide a support structure outside the lower electrode to avoid deformation of the lower electrode. [0003] In the prior art, carbon-containing materials are usually used a...

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Problems solved by technology

[0003] In the prior art, carbon-containing materials are usually used as the support layer of the lower electrode, but the carbon-containing support layer will react during the subsequent deposition of the high-order dielectric layer, causing carbon pollution and resulting in a higher leakage rate of the capacitor

When a carbon-free material is used as the support layer of the lower electrode, the etching solution has a relatively high etching rate for the carbon-free support layer, so that in the process of patterning the top support structure of the lower electrode, The structure of the support layer will be damaged, affecting the structural stability of the capacitor

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