Forming method for semiconductor structure and semiconductor structure

Abstract

A forming method for a semiconductor structure and the semiconductor structure are provided. The forming method of the semiconductor structure includes: providing a substrate, wherein separate bit line structures are formed on the substrate; forming a first sacrificial layer on a sidewall of a bit line structure; forming first dielectric layer filling gaps between adjacent bit line structures; patterning a first dielectric layer to form vias, wherein the vias expose active regions of the substrate, and the vias and remaining parts of the first dielectric layers are alternately arranged in an extension direction of the bit line structures; forming a second sacrificial layer on sidewalls of a via, and filling the via to form a contact plugs; forming a contact structure on the contact plug; and removing the first sacrificial layer to form first air gap, and removing the second sacrificial layer to form a second air gap.