Preparation method of semiconductor structure

• Main Author: LIU XIANZHOU
• Format: Patent
• Language: Chinese; English
• Published: 29.07.2022
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

The invention provides a preparation method of a semiconductor structure, and the method comprises the steps: providing a substrate, forming a stacking layer on the substrate, and enabling the stacking layer to comprise a floating gate polycrystalline silicon layer, a silicon nitride layer and an advanced pattern film layer which are sequentially stacked on the substrate; etching the stack layer and a part of the substrate to form an opening, wherein the opening penetrates through the stack layer and extends into the substrate; removing the advanced pattern film layer; and forming a shallow trench isolation structure in the opening. The advanced pattern film layer is used as a mask for etching to form the opening, so that the opening has better morphological characteristics, and the introduction of the advanced pattern film layer can reduce the thickness of the silicon nitride layer on the basis of the original process, so that the depth of the opening is smaller after the advanced pattern film layer is remov