Method for fabricating a semiconductor structure with pillar array and semiconductor structure

Abstract

Embodiments relate to a method for fabricating a semiconductor structure. The method includes: providing a substrate, where pillars arranged in an array are formed on a surface of the substrate, and bit lines extending along a first direction are formed at bottoms of the pillars; forming, between adjacent two of the pillars, a first groove extending along a second direction; forming an isolation layer on the substrate, where the isolation layer is filled in the first groove and is filled between adjacent two of the bit lines; etching the isolation layer to expose a surface of the pillar, where a first sub isolation layer positioned in the first groove is lower than a second sub isolation layer; forming a word line surrounding a side wall of the pillar, where a surface of the word line is not higher than a surface of the second sub isolation layer; and forming a dielectric layer on the word line.