Trench structure of semiconductor device and manufacturing method thereof

Abstract

A trench structure of a semiconductor device includes a substrate, an isolation structure, and a liner layer. The substrate has a trench therein. The isolation structure is disposed in the trench. The liner layer is disposed between the substrate and the isolation structure. The liner layer includes nitrogen, and the liner layer has spatially various nitrogen concentration. The invention also provides a method for manufacturing the trench structure of the semiconductor device.

Description

technical field [0001] The present invention generally relates to the field of semiconductors, and more specifically, to a trench structure of a semiconductor device and a manufacturing method thereof. Background technique [0002] Trench structures, such as shallow trench isolations (STIs), are used to separate and isolate active regions on a semiconductor wafer from each other. As the circuit density continues to increase, the width of the trenches of the STI decreases continuously, thereby increasing the aspect ratio of the trenches of the STI. The aspect ratio of a trench (or gap) is defined as the trench height (or gap height) divided by the trench width (or gap width). Incomplete gapfill results in undesired voids, and when undesired voids are exposed during removal of excess dielectric, undesired gapfill increases the risk of including undesired defects. These voids can also lead to insufficient isolation between active regions. The presence of voids in STI can aff...

AI Technical Summary

Problems solved by technology

Incomplete gap filling results in undesired voids and increases the risk of including undesired defects when undesired voids are exposed during removal of excess dielectric

These voids can also lead to insufficient isolation between active regions

Presence of voids in STI affects yield

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