Method for manufacturing shallow groove isolation structure

Abstract

The invention discloses a method for manufacturing a shallow groove isolation structure, which comprises: forming a hard mask of which an opening exposes from a substrate, and oxidizing the substrate in an oxygen atmosphere; and forming a shallow groove on the substrate at the position of the opening by a dry etching method after the oxidation treatment. The method for manufacturing the shallow groove isolation structure can form a relatively round shallow groove top chamber and reduce the probability of process defects.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a manufacturing method of a shallow trench isolation structure. Background technique [0002] Currently, device isolation using shallow trench isolation technology has become a conventional technology. Figure 1 ~ Figure 4 It is a schematic diagram of a part of the manufacturing process of a common shallow trench isolation structure. refer to figure 1 As shown, first, a field oxide layer 11 and a nitride layer 12 are sequentially formed on a silicon substrate 10 . refer to figure 2 As shown, then, a photoresist layer is formed on the nitride layer 12, and a photoresist pattern 13 is formed by photolithography, and the photoresist pattern 13 is used to define the shape of the shallow trench. refer to image 3 As shown, thereafter, using the photoresist pattern 13 as a mask, the nitride layer 12 and the field oxide layer 11 are sequentially etched to form ...

AI Technical Summary

Problems solved by technology

[0009] The present invention solves the problem that there is a sharp chamfer at the top of the shallow trench formed in the prior art, which causes the thickness of the subsequently formed gate oxide layer to be relatively thin here, and breakdown is prone to occur

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