Patent ID: 6235576
Filing Date: 2001-05-22
Classification: H01L

Abstract:
A method for manufacturing a cylindrical capacitor on a semiconductor substrate, comprising the steps of:providing a semiconductor substrate having a source/drain region thereon;forming a first insulation layer over the substrate;forming a node contact in the first insulation layer such that the node contact connects electrically with the source/drain region;forming a first conductive layer over the first insulation layer;forming a second insulation layer over the first conductive layer, and then patterning the second insulation layer to retain a portion of the second insulation layer above the node contact;forming spacers on the sidewalls of the patterned second insulation layer, wherein the spacers are formed from a material that differs from both the second insulation layer and the first conductive layer;performing a first anisotropic etching operation using the patterned second insulation layer and the spacers as a mask to etch away a portion of the first conductive layer so that a protruding slab structure is carved out of the first conductive layer, wherein the protruding slab is located above the node contact;removing the patterned second insulation layer to expose the protruding slab; then, as the next step after removing the patterned second insulation layer, performing a second anisotropic etching operation using the spacers as a mask and the first insulation layer as an etching stop layer to etch away a portion of the first conductive layer, thereby forming a cylindrical structure that serves as a lower electrode;removing the spacers;forming a dielectric layer over the cylindrical structure; andforming a second conductive layer over the dielectric layer, thereby forming a complete capacitor.