Method for manufacturing semiconductor device comprising contact void surrounding bit line

Abstract

A method for manufacturing a semiconductor device includes: forming an isolation member defining an active region in a substrate; forming a first insulating layer having a bit line contact over the substrate; forming a second insulating layer having a bit line opening on the first insulating layer; forming a bit line structure in the bit line opening, the bit line structure being electrically connecting to the bit line contact, and a contact void being formed surrounding the bit line structure and exposing a portion of the bit line contact; conformally forming a nitride spacer layer over the bit line structure, the second insulating layer, and the conductive contact; conformally forming a plasma oxide layer over the nitride spacer layer; and performing a wet cleaning process by using an aqueous solution containing negatively charged ions.