US 2003/0134470 A1 · Layer structure having contact hole, fin-shaped capacitor using the layer structure, method of producing the fin-shaped capacitor, and dynamic random access memory having the fin-shaped capacitor

Abstract

A method of forming a structure having a contact hole includes the steps of (a) forming an insulating layer on a first conductive layer, (b) forming a second conductive layer on the insulating layer, (c) forming an opening in the second conductive layer, (d) forming a conductive sidewall around an inner wall of the first conductive layer defining the opening, (e) selectively etching the insulating layer in a state where the second conductive layer and the conductive sidewall function as etching masks, so that the contact hole having a width smaller than that of the opening and defined by the conductive sidewall is formed, and the first conductive layer is exposed through the contact hole, and (f) removing the second conductive layer and the conductive sidewall.

Claims73

Dependent claims

A method of forming a structure having a contact hole comprising the steps of:

(a) forming an insulating layer on a first conductive layer;
(b) forming a second conductive layer on said insulating layer;
(c) forming an opening in said second conductive layer;
(d) forming a conductive sidewall around an inner wall of said first conductive layer defining said opening;
(e) selectively etching said insulating layer in a state where said second conductive layer and said conductive sidewall function as etching masks, so that said contact hole having a width smaller than that of said opening and defined by said conductive sidewall is formed, and said first conductive layer is exposed through said contact hole;
and
(f) removing said second conductive layer and said conductive sidewall.

4 more elements

A dynamic random access memory comprising:

a semiconductor substrate having a first diffusion region and a second diffusion region of a transfer transistor;
a first insulating layer having a first contact hole exposing said first diffusion region, and a second contact hole exposing said second diffusion region;
a word line covered by said first insulating layer;
a stacked capacitor which is in contact with said first diffusion region through said first contact hole;
a bit line which is in contact with said second diffusion region through said second contact hole;
and
a second insulating layer covering said stacked capacitor,
wherein:
said stacked capacitor comprises a storage electrode, a dielectric film and a cell plate;
said storage electrode which is in contact with said first diffusion region through said first contact hole has a first fin having a first portion, a second portion and a third portion;
said first portion has a first opening having a width greater than that of said first contact hole;
said second portion serving as a sidewall is formed around an inner wall of said first portion defining said first opening, so that a second opening has a width substantially identical to that of said first contact hole;
and
said third portion extends on said first and second portions, substantially vertically extends in said first contact hole, and is in contact with said first diffusion region.

11 more elements

A dynamic random access memory comprising:

a semiconductor substrate having a first diffusion region and a second diffusion region of a transfer transistor;
a first insulating layer having a first contact hole exposing said first diffusion region, and a second contact hole exposing said second diffusion region;
a word line covered by said first insulating layer;
a stacked capacitor which is in contact with said first diffusion region through said first contact hole;
a bit line which is in contact with said second diffusion region through said second contact hole;
and
a second insulating layer covering said stacked capacitor,
wherein:
said stacked capacitor comprises a storage electrode, a dielectric film and a cell plate;
and
said storage electrode which is in contact with said first diffusion region through said first contact hole has a plurality of first fin-shaped portions located outside of said first contact hole, a second portion connecting said first fin-shaped portions to each other, and a third portion extending on an uppermost one of said first fin-shaped portions and said second portion, substantially vertically extending in said first contact hole, and being in contact with said first diffusion region.

8 more elements

A method of producing a fin-shaped capacitor in a dynamic random access memory comprising the steps of:

(a) forming a first insulating layer on a semiconductor substrate having a diffusion region;
(b) forming a first conductive layer having a first opening on said first insulating layer;
(c) forming a conductive sidewall around an inner wall of said first conductive layer defining said first opening, said conductive sidewall defining a second opening having a width smaller than that of said first opening;
(d) selectively etching said first insulating layer in a state where said first conductive layer and said conductive sidewall function as etching masks, so that said diffusion region is exposed through a contact hole formed in said first insulating layer and having a width substantially identical to that of said second opening;
(e) forming a second conductive layer on said first conductive layer, said conductive sidewall and said diffusion region exposed through said contact hole;
(f) forming, on said second conductive layer, a second insulating layer having a third opening having a width substantially identical to that of said first opening;
(g) forming a third conductive layer on said second insulating layer and said second conductive layer through said third opening;
(h) patterning said first and second conductive layers and said second insulating layer into a shape of a storage electrode of said fin-shaped capacitor;
(i) isotropically etching said second insulating layer so as to be removed;
(j) forming a dielectric film around an exposed surface of said storage electrode;
and
(k) forming a cell plate around said storage electrode covered by said dielectric film.

9 more elements

A method of producing a fin-shaped capacitor in a dynamic random access memory comprising the steps of:

(a) forming a first insulating layer on a semiconductor substrate having a diffusion region;
(b) forming a plurality of stacked-layer structures, a lowermost one of said stacked-layer structures being formed on said first insulating layer, each of said stacked-layer structures having a spacer layer and a first conductive layer;
(c) forming a first opening in said stacked-layer structures except said spacer layer of said lowermost one of said stacked-layer structures;
(d) forming a conductive sidewall around an inner wall of said stacked-layer structures defining said first opening, said conductive sidewall defining a second opening having a width smaller than that of said first opening;
(e) selectively etching said spacer layer of the lowermost one of said stacked-layer structures and said first insulating layer in a state where said first conductive layer of an uppermost one of said stacked layer structures and said conductive sidewall function as masks, so that said diffusion region is exposed through a contact hole formed in said spacer layer of the lowermost one of said stacked-layer structures and said first insulating layer;
(f) forming a second conductive layer on said first conductive layer of the uppermost one of said stacked-layer structures, said conductive sidewall and said diffusion region exposed through said contact hole;
(g) patterning said second conductive layer and said stacked-layer structures except said spacer layer of the lowermost one of said stacked-layer structures into a shape of a storage electrode of said fin-shaped capacitor;
(h) isotropically etching said spacer layer of each of said stacked-layer structures so that said spacer layer is removed;
(i) forming a dielectric film around said storage electrode;
and
(j) forming a cell plate around said storage electrode covered by said dielectric film.

8 more elements

A method of producing a fin-shaped capacitor in a dynamic random access memory comprising the steps of:

(a) forming a first insulating layer on a semiconductor substrate having a diffusion region;
(b) forming a plurality of stacked-layer structures, a lowermost one of said stacked-layer structures being formed on said first insulating layer, each of said stacked-layer structures having a spacer layer and a first conductive layer;
(c) forming a first opening in said stacked-layer structures;
(d) forming a conductive sidewall around an inner wall of said stacked-layer structures defining said first opening, said conductive sidewall defining a second opening having a width smaller than that of said first opening;
(e) selectively etching said first insulating layer in a state where said first conductive layer of an uppermost one of said stacked layer structures and said conductive sidewall function as masks, so that said diffusion region is exposed through a contact hole formed in said first insulating layer;
(f) forming a second conductive layer on said first conductive layer of the uppermost one of said stacked-layer structures, said conductive sidewall and said diffusion region exposed through said contact hole;
(g) patterning said second conductive layer and said stacked-layer structures into a shape of a storage electrode of said fin-shaped capacitor;
(h) isotropically etching said spacer layer of each of said stacked-layer structures so that said spacer layer is removed;
(i) forming a dielectric film around said storage electrode;
and
(j) forming a cell plate around said storage electrode covered by said dielectric film.

8 more elements

A method of producing a fin-shaped capacitor in a dynamic random access memory comprising the steps of:

(a) forming a first insulating layer on a semiconductor substrate having a diffusion region;
(b) forming a plurality of stacked-layer structures, a lowermost one of said stacked-layer structures being formed on said first insulating layer, each of said stacked-layer structures having a spacer layer and a first conductive layer;
(c) forming a contact hole in said stacked-layer structures and said first insulating layer so that said diffusion layer is exposed through said contact hole;
(d) forming a second conductive layer on said first conductive layer of an uppermost one of said stacked-layer structure and said diffusion layer exposed through said contact hole, said second conductive layer substantially vertically extending along an inner wall of said contact hole;
(e) patterning said second conductive layer and said stacked-layer structures into a shape of a storage electrode of said fin-shaped capacitor;
(f) isotropically etching said spacer layer of each of said stacked-layer structures so that said spacer layer is removed;
(i) forming a dielectric film around said storage electrode;
and
(j) forming a cell plate around said storage electrode covered by said dielectric film.

6 more elements

Dependencies are inferred from the claim text.

Layer structure having contact hole, fin-shaped capacitor using the layer structure, method of producing the fin-shaped capacitor, and dynamic random access memory having the fin-shaped capacitor

Life of this patent

Layer structure having contact hole, fin-shaped capacitor using the layer structure, method of producing the fin-shaped capacitor, and dynamic random access memory having the fin-shaped capacitor

Life of this patent

Abstract

Claims73