Process of manufacturing a DRAM cell capacitor having increased trench capacitance
AssigneeInternational Business Machines Corporation
InventorsChristopher N. Collins, Harris C. Jones, James P. Norum, Stefan Schmitz
Life of this patent
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Abstract
A trench capacitor having an increased surface area. In one embodiment, the trench capacitor is a dual trench capacitor having a first trench and a second trench wherein inner walls of the trenches electrically connect. The invention also includes a single trench capacitor wherein the trench is curved around an axis substantially perpendicular to a substrate surface.
Claims6
A process of fabricating a trench capacitor having a trench extending in a substrate, said trench having side walls, wherein the trench is curved around an axis substantially perpendicular to a substrate surface, said process comprising the steps of:
- forming a mask on a substrate, said mask having an opening curved around an axis substantially perpendicular to a substrate surface, said opening extending to the substrate, and said mask having a mask isolation portion defined by said curved opening in said mask;
- etching said substrate through said opening to form said trench, and etching the mask isolation portion and the surface of said substrate underlying said mask isolation portion.
Dependencies are inferred from the claim text.