SEMICONDUCTOR DEVICE AND METHOD OF FORMING THE SAME

A method of forming a semiconductor device includes forming first sacrificial patterns on a substrate, the first sacrificial patterns spaced apart from each other, forming a capping layer on the first sacrificial patterns, forming a gap insulating layer spaced apart from a lower portion of the capping layer between the first sacrificial patterns in a vertical direction, planarizing the gap insulating layer and the capping layer to expose the first sacrificial patterns, removing the first sacrificial patterns to form trenches, and forming conductive patterns in the trenches, the conductive patterns having an air gap therebetween and between the lower portion of the capping layer and the gap insulating layer.