Abstract: Exemplary embodiments of the present invention disclose process steps to form high aspect ratio structures, such as a capacitor during semiconductor fabrication by the steps of: forming a first layer of planarized boro-phospho-silicate glass (BPSG) material over a conductive region; forming a first opening in said first layer of planarized BPSG material, said first opening aligning to said conductive region; forming a planarized polysilicon material into said first opening; forming a second layer of planarized BPSG material directly on said first layer of planarized BPSG material and said planarized polysilicon material; forming a second opening in said second layer of planarized BPSG material to expose a major portion of said planarized polysilicon material; removing said planarized polysilicon material to expose said underlying conductive region, said step of removing said planarized polysilicon comprises an etch possessing an etching selectivity ratio of polysilicon material to BPSG material that is greate

Abstract: Exemplary embodiments of the present invention disclose process steps to form high aspect ratio structures, such as a capacitor during semiconductor fabrication by the steps of: forming a first layer of planarized boro-phospho-silicate glass (BPSG) material over a conductive region; forming a first opening in said first layer of planarized BPSG material, said first opening aligning to said conductive region; forming a planarized polysilicon material into said first opening; forming a second layer of planarized BPSG material directly on said first layer of planarized BPSG material and said planarized polysilicon material; forming a second opening in said second layer of planarized BPSG material to expose a major portion of said planarized polysilicon material; removing said planarized polysilicon material to expose said underlying conductive region, said step of removing said planarized polysilicon comprises an etch possessing an etching selectivity ratio of polysilicon material to BPSG material that is greate

Abstract: Methods and apparatus for forming word line stacks comprise one, or a combination of the following: a silicon diffusion barrier layer, doped with oxygen or nitrogen, coupled between a bottom silicon layer and a conductor layer; an amorphous silicon diffusion barrier coupled between a polysilicon layer and a conductor layer; a thin nitride layer coupled between a bottom silicon layer and a titanium silicide conductor layer, and a bottom silicon layer coupled to a conductor layer, which comprises C54-titanium silicide. Word line stacks formed by the methods of the invention are used in sub-0.25 micron line width applications and have a lower resistivity and improved thermal stability.

Abstract: Methods and apparatus for forming word line stacks comprise forming a thin nitride layer coupled between a bottom silicon layer and a conductor layer. In a further embodiment, a diffusion barrier layer is coupled between the thin nitride layer and the bottom silicon layer. The thin nitride layer is formed by annealing a silicon oxide film in a nitrogen-containing ambient.