Methods of forming shallow trench isolation structures in semiconductor devices

Abstract

Methods of forming a shallow trench isolation structures in semiconductor devices are disclosed. A disclosed method comprises forming a first oxide layer, a nitride layer, and a second oxide layer on a substrate; forming a trench defining first and second active areas by etching the second oxide layer, the nitride layer, the first oxide layer, and the substrate in a predetermined area; forming a third oxide layer along an inside of the trench; forming a fourth oxide layer to fill up the trench; forming a sacrificial oxide layer on the fourth oxide layer; and removing the sacrificial oxide layer, the fourth oxide layer, the third oxide layer, the second oxide layer, and the nitride layer so as to form the shallow trench isolation. Thus, it is possible to minimize the damage of a narrow active area when forming an element isolation area through an STI process.

Dependencies are inferred from the claim text.