Method for improving gate oxide breakdown voltage

Abstract

The invention discloses a method for improving gate oxide breakdown voltage, and particularly provides a shallow trench gate oxide layer. A chlorine processing sacrificial oxide layer is developed after the gate oxide layer is pre-cleaned; the developed sacrificial oxide layer is removed by using an acid bath; and a gate oxide structural layer is developed on the surface of the gate oxide layer. According to the method disclosed by the invention, optimization is carried out on corners of the shallow trench gate layer through a mode of additionally arranging the chlorine processing sacrificial oxide layer and removing the chlorine processing sacrificial oxide layer, thereby achieving an effect of enabling the gate oxide corners to be smooth, and avoiding a problem that the gate oxide breakdown voltage is lowered because of the corners of the shallow trench gate oxide layer is sharp. The gate oxide thickness of a semiconductor device prepared by adopting the method disclosed by the invention achieves requirements, the corners of the shallow trench gate oxide layer are smooth, obvious sharp corners does not exist, and the breakdown voltage of the gate oxide layer is also within the normal range.

Description

technical field [0001] The invention relates to the field of semiconductor manufacturing, in particular to a method for improving gate oxide breakdown voltage based on chlorine treatment of a sacrificial oxide layer. Background technique [0002] In semiconductor devices, the gate oxide process is the most critical process condition for determining the performance of semiconductor devices, and the breakdown voltage of the gate oxide is the key test condition for determining the performance of the gate oxide, so the breakdown voltage of the gate oxide reflects the performance of the device. Basic requirements, with the rapid development of the electronics industry and VLSI, the size of semiconductor devices is constantly decreasing. While the device size is proportionally reduced, the working voltage is not proportionally reduced, which makes thin gate oxide The electric field strength in the layer increases, and the breakdown voltage of the device decreases, which directly a...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to solve the problem that the breakdown voltage of the gate oxide becomes lower due to the excessive leakage current caused by the excessively sharp shallow channel corners caused by the excessive thickness of the gate oxide, thereby effectively avoiding device failure

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