Semiconductor device and capacitor hole preparation method of semiconductor device

Abstract

The present application relates to a preparation method of a capacitor hole and a semiconductor device including the capacitor hole. The preparation method includes: forming a stacked first dielectric layer, a first mask layer, a first pattern layer, a second dielectric layer, and a second dielectric layer on a substrate. A mask layer and a second pattern layer; the first pattern layer and the second pattern layer form a grid; a third mask layer is formed on the second pattern layer to cover the second mask layer of the edge area and expose the middle area the second mask layer; etch the exposed second mask layer until the second dielectric layer is exposed; etch the exposed second dielectric layer until the first pattern layer and the first mask layer are exposed; remove the third mask film layer, etch the exposed first mask layer and the second pattern layer and the second mask layer in the edge area until the first dielectric layer is exposed, the etching selectivity ratio of the second mask layer and the first mask layer If it is greater than 1, the exposed first dielectric layer is etched to form a capacitor hole. In the present application, while etching the first mask layer in the middle area, the line height in the edge area is etched and reduced.

Description

technical field [0001] The invention relates to the field of semiconductor device manufacturing, in particular to a semiconductor device and a method for preparing a capacitance hole of the semiconductor device. Background technique [0002] Semiconductor devices, such as dynamic random access memory (DRAM), record information by storing and releasing electric charge through capacitors. The capacitor is specifically prepared on the semiconductor substrate. In order to increase the density of the semiconductor substrate and improve the degree of integration, a trench capacitor is usually used. First, a trench with a certain depth is opened as a capacitor hole, and then the electrode plate and the capacitor are sequentially deposited in the capacitor hole. The dielectric layer and the upper electrode plate form a trench capacitor. [0003] At present, the process of opening capacitor holes will leave a certain height of sidewalls in the edge region of the semiconductor device...

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Problems solved by technology

[0004] Based on this, this application aims at the technical problem that the sidewalls in the edge region are easy to collapse when the capacitor hole is opened, and proposes a method for preparing a capacitor hole of a semiconductor device.

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