Method of manufacturing semiconductor device

Abstract

A method of manufacturing a semiconductor device includes providing a precursor structure including a first capacitor and a second capacitor on a substrate; forming a first vertical transistor and a second vertical transistor respectively over the first capacitor and the second capacitor, in which the first vertical transistor includes a first word line having a first top width and a first bottom width smaller than the first top width, the second vertical transistor includes a second word line having a second top width and a second bottom width smaller than the second top width; and forming an air gap between the first vertical transistor and the second vertical transistor.

Dependencies are inferred from the claim text.