Manufacturing method of semiconductor structure

A manufacturing method of a semiconductor structure, comprising:

• providing a substrate, wherein the substrate comprises multiple active regions and an isolation structure for isolating each of the active regions;
• the multiple active regions are arranged in several columns along a first direction;
• forming multiple spaced first isolation sidewall structures on the substrate, wherein first opening regions are formed between adjacent first isolation sidewall structures, and each of the first opening regions is used to expose at least two columns of active regions;
• forming a conductive layer on the substrate located in the first opening regions, wherein a height of the conductive layer is lower than heights of the first isolation sidewall structures;
• and
• removing part of the conductive layer located in the first opening region to form two spaced bit line structures, wherein the two bit line structures are respectively in contact with one of the two first isolation sidewall structures forming the first opening region;
• wherein the forming multiple spaced first isolation sidewall structures on the substrate comprises:
• sequentially stacking a sacrificial layer and a photoresist layer on the substrate;
• patterning the photoresist layer to form multiple second opening regions and multiple shielding regions for isolating each of the second opening regions in the photoresist layer, wherein a projection of each of the shielding regions on the substrate overlaps with at least two columns of active regions;
• removing the sacrificial layer located in the second opening regions to retain the sacrificial layer located below the shielding regions, wherein the sacrificial layer located below the shielding regions forms isolation portions, and isolation regions are formed between adjacent isolation portions;
• and
• forming the first isolation sidewall structures in the isolation regions;
• the forming the first isolation sidewall structures in the isolation regions comprises:
• forming a first isolation structure on sidewalls of the isolation regions, bottom walls of the isolation regions and top surfaces of the isolation portions;
• forming a first dielectric layer on the first isolation structure, wherein the first dielectric layer fills the isolation regions;
• and
• removing part of the first isolation structure and part of the first dielectric layer on the top surfaces of the isolation portions and the isolation portions, and retaining the first isolation structure and the first dielectric layer on the substrate, wherein the retained first isolation structure and first dielectric layer form the first isolation sidewall structures;
• and
• the removing part of the first isolation structure and part of the first dielectric layer on the top surfaces of the isolation portions and the isolation portions comprises:
• removing the first dielectric layer arranged on a top surface of the first isolation structure and part of the first dielectric layer arranged in the isolation regions, such that the first dielectric layer disposed in the isolation regions forms recesses;
• forming a barrier layer in the recesses;
• and
• using the barrier layer as a mask to remove the isolation portions and the first isolation structure on the top surfaces of the isolation portions.