Method for producing STI lining oxide layer

Abstract

The invention provides a method for producing an STI lining oxide layer which is prepared directly on a silicon substrate etched in a sealing device. The method comprises steps as follows: 1, rising temperature primarily to the sealing device and introducing inert gas; 2, rising temperature again to the sealing device to a temperature for producing the STI lining oxide layer, introducing inert gas and oxidizing gas into the sealing device for growing the SIT lining oxide layer; 3, performing anneal to the STI lining oxide layer, and introducing inert gas and oxidizing gas into the sealing device; 4, reducing temperature primarily to the sealing device and introducing inert gas and oxidizing gas into the sealing device; and 5, reducing temperature again to the sealing device and introducing inert gas into the sealing device. The method can effectively solve the problem of active area damage caused by the traditional production method, and improves the production efficiency as well as the coverage rate of the lining oxide layer.

Description

technical field [0001] The invention relates to the field of STI fabrication, in particular to a method for reducing damage to an active region caused when an STI lining oxide layer is fabricated. Background technique [0002] Shallow Trench Isolation (STI) is a commonly used isolation technology for semiconductor integrated chips at present. STI is made in the isolation device for isolation, and insulators are filled in the shallow trenches to achieve the purpose of insulating the devices to be isolated. The STI structure is usually formed by first depositing a silicon nitride layer on a semiconductor substrate, then patterning the silicon nitride layer to form a hard mask, and then etching the substrate to form steep trenches between adjacent elements. Finally, an insulator is filled in the trench to form an element isolation structure. At present, silicon oxide is usually used as the insulator in the shallow trenches, and the filling of the silicon oxide in the shallow ...

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Problems solved by technology

[0003] The present invention provides a method for making the lining oxide layer of STI, so as to avoid the formation of silicon nitride in the active region on the substrate under the condition of nitrogen annealing in the traditional manufacturing of the lining oxide layer of STI, and solve the problems caused by the subsequent silicon nitride removal process. source damage problem

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