Semiconductor structure, forming method thereof and ozone cleaning equipment

Abstract

The invention discloses a semiconductor structure, a forming method thereof and ozone cleaning equipment, and the forming method of the semiconductor structure comprises the steps: carrying out the dry etching of a silicon wafer in the semiconductor structure, and forming a groove; the groove is cleaned; forming an oxide layer on the surface of the groove; and etching off the oxide layer, and forming a smooth curved surface between the bottom and the side wall of the groove. According to the invention, after the groove is etched, part of residual silicon particles in the groove are cleaned; performing oxidation treatment on the surface of the groove, so that the silicon particles on the surface of the upper half part of the groove and remaining in the bottom of the groove form a silicon dioxide layer; the silicon dioxide layer is etched off subsequently, that is, part of the silicon wafer in the upper half part of the groove and silicon particles at the bottom are removed, so that the opening of the groove is enlarged, and the side wall and the bottom of the groove form a curved surface; therefore, the oxide medium in the subsequent process can be fully filled in the groove, no gap is generated, and no leakage current is generated.

Description

technical field [0001] The present application relates to the technical field of chip manufacturing, in particular to a semiconductor structure, its forming method and ozone cleaning equipment. Background technique [0002] The etching process is a commonly used process in the manufacturing process of semiconductor devices. In the manufacturing process of semiconductor integrated circuits, etching is the process of selectively removing unnecessary materials from the surface of silicon wafers by chemical or physical methods. In terms of process, etching can be divided into wet etching and dry etching; among them, the main feature of wet etching is isotropic etching, and dry etching uses plasma to perform anisotropic etching. Etching can strictly control vertical and horizontal etching. [0003] At present, there are three methods of digging trenches in the manufacture of semiconductor devices, namely: wet etching, dry etching, wet etching + dry etching. For semiconductor dev...

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Problems solved by technology

[0003] At present, there are three methods of digging trenches in the manufacture of semiconductor devices, namely: wet etching, dry etching, wet etching + dry etching. For semiconductor devices with photolithography accuracy below 0.18um, dry However, due to the anisotropy of dry etching, an angle of 90° will be formed between the bottom of the trench and the sidewall, resulting in incomplete filling of the trench with an oxide medium in the subsequent process, which is prone to failure. gap, which will result in increased leakage current

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