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US 6,632,719 B1Granted
Capacitor structures with recessed hemispherical grain silicon
AssigneeMicron Technology, Inc.
InventorsScott J. DeBoer, Whonchee Lee
Life of this patent
Estimating the term…
Abstract
Capacitor structures and capacitors with edge zones that are substantially free of hemispherical grain silicon along the upper edges of the capacitor structures are disclosed. The resulting recessed hemispherical grain silicon layers reduce or prevent separation of particles from the hemispherical grain silicon layer during subsequent manufacturing processes, thereby reducing defects and increasing throughput. Also disclosed are methods of forming the capacitor structures and capacitors in which the silicon layer used to form the hemispherical grain silicon is selectively removed to provide an edge zone that is substantially free of hemispherical grain silicon.
Claims26
A method of forming a capacitor structure comprising:
- providing a cavity in a substrate, the cavity comprising a sidewall structure, an opening, and a bottom opposite the opening of the cavity;
- providing a first layer on an inner surface of the sidewall structure, wherein the first layer is electrically conductive;
- providing a second layer on substantially all of the first layer, the second layer comprising hemispherical grain silicon precursor;
- providing fill material in the cavity, wherein at least an edge of the second layer is exposed proximate the opening of the cavity;
- removing the hemispherical grain silicon precursor in the second layer proximate the opening of the cavity to form an edge zone about the opening of the cavity, the edge zone extending from the opening of the cavity towards the bottom of the cavity;
- and
- converting the hemispherical grain silicon precursor in the second layer to hemispherical grain silicon, wherein the edge zone is substantially free of the hemispherical grain silicon.
4 more elements
A method of forming a capacitor structure comprising:
- providing a cavity in a substrate, the cavity comprising a sidewall structure, an opening, and a bottom opposite the opening of the cavity;
- providing a first layer on an inner surface of the sidewall structure, wherein the first layer comprises doped silicon;
- providing a second layer on substantially all of the first layer, the second layer comprising hemispherical grain silicon precursor;
- providing fill material in the cavity, wherein at least an edge of the second layer is exposed proximate the opening of the cavity;
- removing the hemispherical grain silicon precursor in the second layer proximate the opening of the cavity to form an edge zone about the opening of the cavity, the edge zone extending from the opening of the cavity towards the bottom of the cavity;
- and
- converting the hemispherical grain silicon precursor in the second layer to hemispherical grain silicon, wherein the edge zone is substantially free of the hemispherical grain silicon.
4 more elements
A method of forming a capacitor structure comprising:
- providing a cavity in a substrate, the cavity comprising a sidewall structure, an opening, and a bottom opposite the opening of the cavity;
- providing a first layer on an inner surface of the sidewall structure, wherein the first layer comprises doped silicon;
- providing a second layer on substantially all of the first layer, the second layer comprising hemispherical grain silicon precursor;
- providing fill material in the cavity, wherein at least an edge of the second layer is exposed proximate the opening of the cavity;
- removing the hemispherical grain silicon precursor in the second layer proximate the opening of the cavity by contacting at least the exposed edge of the second layer with an etchant comprising TMAH at a concentration of greater than 2.25% (by weight) to form an edge zone about the opening of the cavity, the edge zone extending from the opening of the cavity towards the bottom of the cavity;
- and
- converting the hemispherical grain silicon precursor in the second layer to hemispherical grain silicon, wherein the edge zone is substantially free of the hemispherical grain silicon.
4 more elements
A method of forming a capacitor structure comprising:
- providing a cavity in a substrate, the cavity comprising a sidewall structure, an opening, and a bottom opposite the opening of the cavity;
- providing a first layer on an inner surface of the sidewall structure, wherein the first layer comprises doped silicon;
- providing a second layer on substantially all of the first layer, the second layer comprising hemispherical grain silicon precursor;
- providing fill material in the cavity, wherein at least an edge of the second layer is exposed proximate the opening of the cavity;
- removing the hemispherical grain silicon precursor in the second layer proximate the opening of the cavity by contacting at least the exposed edge of the second layer with an etchant comprising TMAH at a concentration of greater than 2.25% (by weight) and less than 3% (by weight) to form an edge zone about the opening of the cavity, the edge zone extending from the opening of the cavity towards the bottom of the cavity;
- and
- converting the hemispherical grain silicon precursor in the second layer to hemispherical grain silicon, wherein the edge zone is substantially free of the hemispherical grain silicon.
4 more elements
A method of forming a capacitor structure comprising:
- providing a cavity in a substrate, the cavity comprising a sidewall structure, an opening, and a bottom opposite the opening of the cavity;
- providing a first layer on an inner surface of the sidewall structure, wherein the first layer is electrically conductive;
- providing a second layer on substantially all of the first layer, the second layer comprising hemispherical grain silicon;
- providing fill material in the cavity, wherein at least an edge of the second layer is exposed proximate the opening of the cavity;
- and
- removing the hemispherical grain silicon in the second layer proximate the opening of the cavity to form an edge zone about the opening of the cavity, the edge zone extending from the opening of the cavity towards the bottom of the cavity, wherein the edge zone is substantially free of the hemispherical grain silicon.
3 more elements
A method of forming a capacitor structure comprising:
- providing a cavity in a substrate, the cavity comprising a sidewall structure, an opening, and a bottom opposite the opening of the cavity;
- providing a first layer on an inner surface of the sidewall structure, wherein the first layer comprises doped silicon;
- providing a second layer on substantially all of the first layer, the second layer comprising hemispherical grain silicon;
- providing fill material in the cavity, wherein at least an edge of the second layer is exposed proximate the opening of the cavity;
- and
- removing the hemispherical grain silicon in the second layer proximate the opening of the cavity to form an edge zone about the opening of the cavity, the edge zone extending from the opening of the cavity towards the bottom of the cavity, wherein the edge zone is substantially free of the hemispherical grain silicon.
3 more elements
A method of forming a capacitor structure comprising:
- providing a cavity in a substrate, the cavity comprising a sidewall structure, an opening, and a bottom opposite the opening of the cavity;
- providing a first layer on an inner surface of the sidewall structure, wherein the first layer comprises doped silicon;
- providing a second layer on substantially all of the first layer, the second layer comprising hemispherical grain silicon;
- providing fill material in the cavity, wherein at least an edge of the second layer is exposed proximate the opening of the cavity;
- and
- removing the hemispherical grain silicon of the second layer proximate the opening of the cavity by contacting at least the exposed edge of the second layer with an etchant comprising TMAH at a concentration of greater than 2.25% (by weight) to form an edge zone about the opening of the cavity, the edge zone extending from the opening of the cavity towards the bottom of the cavity, wherein the edge zone is substantially free of the hemispherical grain silicon.
3 more elements
A method of forming a capacitor structure comprising:
- providing a cavity in a substrate, the cavity comprising a sidewall structure, an opening, and a bottom opposite the opening of the cavity;
- a first layer on an inner surface of the sidewall structure, wherein the first layer comprises doped silicon;
- providing a second layer on substantially all of the first layer, the second layer comprising hemispherical grain silicon;
- providing fill material in the cavity, wherein at least an edge of the second layer is exposed proximate the opening of the cavity;
- and
- removing the hemispherical grain silicon in the second layer proximate the opening of the cavity by contacting at least the exposed edge of the second layer with an etchant comprising TMAH at a concentration of greater than 2.25% (by weight) and less than 3% (by weight) to form an edge zone about the opening of the cavity, the edge zone extending from the opening of the cavity towards the bottom of the cavity, wherein the edge zone is substantially free of the hemispherical grain silicon.
3 more elements
Dependencies are inferred from the claim text.