Patent ID: 6960523

Claim:
A method of improving an etch rate of a first portion of a nitride liner layer relative to an etch rate of a further portion of said nitride liner layer, said first portion of said nitride liner layer being located at least atop an exposed portion of a substrate adjacent to a bottom of at least one stacked structure also located atop said substrate, said further portion of said nitride linear layer being located atop said stacked structure; said method comprising: forming a nitride spacer along the sidewalls of said stacked structure; forming said nitride liner layer over said substrate, said stacked structure, and said nitride spacer; depositing a first insulating layer atop said nitride liner layer at least between two stacked structures and planarizing said first insulating layer; depositing a further insulating layer atop said planarized first insulating layer, said first planarized insulation and said further insulating layer being patterned and selectively atched to form at least one opening to expose said first, said further and another portion of said nitride liner layer, said selective etching leaving said exposed portions of said nitride liner layer intact so that said stacked structures are not exposed; forming an oxide spacer along said exposed another portion of said nitride liner layer, said another portion being formed along said nitride spacer disposed along sidewalls of said stacked structure; and etching said exposed first portion of said nitride liner layer to form at least one opening therein to said substrate, said further portion of said nitride liner layer remaining substantially intact such that said stacked structure is not exposed.