Abstract: An etch rate of a nitride liner layer is improved relative to an etch rate of a nitride cap layer. The nitride liner layer is located at an exposed portion of a substrate adjacent to a stacked structure also located atop the substrate. The nitride cap layer is located atop the stacked structure. An oxide spacer is formed along sidewalls of the stacked structure. The nitride liner layer is patterned and etched to form at least one opening therein to the substrate while the nitride cap layer remains substantially intact.

Abstract: An etch rate of a nitride liner layer is improved relative to an etch rate of a nitride cap layer. The nitride liner layer is located at an exposed portion of a substrate adjacent to a stacked structure also located atop the substrate. The nitride cap layer is located atop the stacked structure. An oxide spacer is formed along sidewalls of the stacked structure. The nitride liner layer is patterned and etched to form at least one opening therein to the substrate while the nitride cap layer remains substantially intact.

Abstract: A method is provided for forming an inside nitride spacer in a deep trench device DRAM cell. The method includes depositing an oxide liner in a trench etched from a semiconductor material, wherein the oxide lines abuts a pad nitride layer, a pad oxide layer under the pad nitride layer, and a recessed gate poly in the trench. The method further includes depositing a spacer material on the oxide liner, removing exposed portions of the oxide layer from the semiconductor, and depositing a poly stud material over the semiconductor wherein the spacer material is encapsulated in poly stud material. The method includes polishing the semiconductor to the top trench oxide layer, and etching the top trench oxide layer.

Abstract: A method is provided for forming an inside nitride spacer in a deep trench device DRAM cell. The method includes depositing an oxide liner in a trench etched from a semiconductor material, wherein the oxide lines abuts a pad nitride layer, a pad oxide layer under the pad nitride layer, and a recessed gate poly in the trench. The method further includes depositing a spacer material on the oxide liner, removing exposed portions of the oxide layer from the semiconductor, and depositing a poly stud material over the semiconductor wherein the spacer material is encapsulated in poly stud material. The method includes polishing the semiconductor to the top trench oxide layer, and etching the top trench oxide layer.

Abstract: The vertical MOSFET structure used in forming dynamic random access memory comprises a gate stack structure comprising one or more silicon nitride spacers; a vertical gate polysilicon region disposed in an array trench, wherein the vertical gate polysilicon region comprises one or more silicon nitride spacers; a bitline diffusion region; a shallow trench isolation region bordering the array trench; and wherein the gate stack structure is disposed on the vertical gate polysilicon region such that the silicon nitride spacers of the gate stack structure and vertical gate polysilicon region form a borderless contact with both the bitline diffusion region and shallow trench isolation region. The vertical gate polysilicon is isolated from both the bitline diffusion and shallow trench isolation region by the nitride spacer, which provides reduced bitline capacitance and reduced incidence of bitline diffusion to vertical gate shorts.