Method for manufacturing gate oxide layer

Abstract

The invention provides a method for manufacturing a gate oxide layer. The method includes the steps of providing a silicon substrate, carrying out the thermal oxidation technology on the silicon substrate to form a silicon dioxide gate oxide layer on the surface of the silicon substrate, carrying out nitrogen injection on the silicon dioxide gate oxide layer with the plasma nitridation technology to form a silicon oxynitride gate oxide layer, carrying out the high-temperature nitridation technology on the silicon oxynitride gate oxide layer to repair crystal lattice damage and form stable Si-N bonds, and carrying out the low-temperature oxidation technology on the silicon oxynitride gate oxide layer after high-temperature nitridation processing is carried out to repair an interface between SiO2 and Si. By means of the method for manufacturing the gate oxide layer, the gate oxide layer after the nitrogen injection is processed with the high-temperature nitridation technology, the Si-N bonds of the silicon oxynitride gate oxide layer are stable, nitrogen atoms on the surface of the silicon oxynitride gate oxide layer are prevented from being continuously volatilized or diffused, and therefore the content of nitrogen in the gate oxide layer is effectively improved and kept stable.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a method for manufacturing a gate oxide layer. Background technique [0002] In semiconductor manufacturing technology, the gate oxide layer is usually used as a dielectric layer to achieve electrical isolation between the gate and the substrate. The performance of the gate oxide layer usually directly affects and determines the electrical characteristics and reliability of semiconductor devices. Therefore, the preparation process of the gate oxide layer is a key step in the semiconductor manufacturing process. [0003] As the feature size of semiconductor devices continues to shrink, the thickness of the gate oxide layer is getting thinner and thinner. As the gate oxide thickness decreases, gate leakage increases exponentially. On the other hand, there is a concentration gradient of impurities between the gate, the gate oxide layer and the silicon substrate...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to provide a method for manufacturing a gate oxide layer to solve the problem of low nitrogen content or unstable nitrogen content in the gate oxide layer in the prior art

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