Semiconductor structure including a plurality of semicondcutor pillars and bit line isolation trenches and method for forming same

Abstract

A method for forming a semiconductor structure includes: providing a semiconductor substrate including a plurality of first semiconductor pillars and bit line isolation trenches arranged at intervals in a first direction; in which the bit line isolation trenches extend in a second direction, the first direction being perpendicular to the second direction; forming a bit line isolation layer in a bit line isolation trench; in which a gap is provided between the bit line isolation layer and the bit line isolation trench, in which the gap is located at a bottom corner of the bit line isolation trench and extends in the second direction, and exposes part of the bottom of the bit line isolation trench; etching a first semiconductor pillar in the first direction through the gap to form a bit line trench; forming a bit line in the bit line trench.