Dynamic random access memory circuitry and integrated circuitry

摘要

A method of forming a conductive contact to a conductive structure includes forming a conductive structure received within and projecting outwardly from a first insulative material. A second different insulative material is deposited. The second insulative material is anisotropically etched effective to form a sidewall etch stop for the conductive structure. A third insulative material is deposited over the conductive structure and the sidewall etch stop. The third insulative material is different in composition from the second insulative material. A contact opening is etched through the third insulative material to the conductive structure using an etch chemistry which is substantially selective to the second insulative material of the sidewall etch stop. Integrated circuitry independent of the method of fabrication is disclosed.