Method for fabricating self-aligned double-layer patterned semiconductor structure

Abstract

The invention provides a manufacturing method of a self-aligned two-layer graph semiconductor structure. The manufacturing method includes the steps that a semiconductor substrate is provided, and a first silicon oxide layer and a silicon nitride layer are formed on the semiconductor substrate; a core graph layer is formed on the silicon nitride layer and made of polycrystalline silicon; an antireflection layer and a photoresist layer are sequentially formed on the core graph layer, and a core graph is defined by the photoresist layer; with the photoresist layer as a mask, etching is conducted on the antireflection layer and the core graph layer, patterns of the core graph are transferred onto the core graph layer, the core graph layer left on the silicon nitride layer has vertical morphology, and second silicon oxide layers with vertical appearance are formed on the two sides of the left core graph layer; with the second silicon oxide layers with the vertical appearance as masks, etching is conducted on the silicon nitride layer and the first silicon oxide layer to form the self-aligned two-layer graph structure with vertical appearance.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a method for manufacturing a self-aligned double-layer pattern semiconductor structure. Background technique [0002] At the node of 20nm and below, self-aligned double-layer patterning (SADP) process has been applied to the production of key semiconductor layers such as active area (AA) and polysilicon (Poly). [0003] Please refer to Figure 1-Figure 7 A schematic cross-sectional structure diagram of a method for fabricating a self-aligned double-layer patterned semiconductor structure in the prior art is shown. Please refer to figure 1 , firstly, a semiconductor substrate 10 is provided, and a silicon nitride layer 11, a core pattern layer 13, a hard mask layer 17, an antireflection layer 14 and a photoresist layer 15 are sequentially formed on the semiconductor substrate 10, and the core The pattern layer 13 is made of amorphous carbon (APF), and the hard mask layer...

AI Technical Summary

Problems solved by technology

Because the silicon oxide layer 16 remaining on both sides of the core pattern layer 13 is inclined, its shape affects the shape of the self-aligned double-layer pattern structure, so that the shape and shape of the self-aligned double-layer pattern structure dimensionally unstable

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