Process for making shallow trench isolation arrangement

Abstract

The invention is a shallow trench isolation construction making method, forming a cushion oxidizing layer and a covering curtain layer on the substrate in turn, delimiting the cushion oxidizing layer, covering curtain layer and partial substrate to form the trench, then forming conformal buffer layer on the trench's internal surface and the surface of the covering curtain layer, converting the buffer layer into oxide layer, then forming an insulating layer in the trench and on the substrate to fill up the trench, then remove the insulating layer and the oxide layer outside the trench until exposing the surface of the covering curtain layer, and finally remove the covering curtain layer and cushion oxidizing layer to form it.

Description

technical field [0001] The present invention relates to a manufacturing method of an integrated circuit device, and in particular to a manufacturing method of a shallow trench isolation (STI). Background technique [0002] Today, as the density of semiconductor components is getting tighter, the isolation between components has become very important. In order to prevent short circuits between adjacent components, an isolation layer is usually added between them. The most traditional and common technology for making isolation layers is regional localization. Oxidation method (LOCOS), and a highly reliable and effective device isolation structure can be obtained at a lower cost. However, the area-localized oxidation method still suffers from several disadvantages, including problems related to known stress generation, formation of bird's beak around the LOCOS field isolation structure, and the like. In particular, the formation of the bird's beak region hinders the improvemen...

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Problems solved by technology

[0006] However, in the known manufacturing process of the shallow trench isolation structure, since the liner oxide layer 108 is formed by thermally oxidizing the silicon in the trench 106, it means that the silicon on the inner surface of the trench 106 must be consumed to form the liner oxide layer 108 , which will increase the outline and size of the shallow trench isolation structure, reduce the actual available active area and increase the design and layout variables, which is not conducive to the miniaturization of components

[0007] Moreover, during the process of removing the silicon nitride layer 104 and the pad oxide layer 102, the corners of the oxide filling 110a will be eroded to form a wrap rounding phenomenon, thereby causing the depression 112

The recess 112 will accumulate charges, and then cause sub-threshold leakage current (sub-threshold leakage current) of the device in the integrated circuit, which is the so-called neck junction effect (kink effect), thereby reducing the reliability and yield of the device reduce

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