Capacitor and method for forming the same

1 . A method, comprising:

forming a sacrificial multi-layer stack including first, second, and third sacrificial layers stacked in a vertical direction on a substrate;

removing the first sacrificial layer to form a first space;

depositing a first dielectric layer and a first electrode material in the first space;

removing the second sacrificial layer to form a second space;

after depositing the first dielectric layer and the first electrode material, depositing a second dielectric layer and a second electrode material in the second space;

removing the third sacrificial layer to form a third space; and

after depositing the second dielectric layer and the second electrode material, depositing a third dielectric layer and a third electrode material in the third space.

2 . The method of claim 1 , wherein forming the sacrificial multi-layer stack comprises:

depositing first, second, and third sacrificial films on the substrate; and

patterning the first, second, and third sacrificial films to form a fin-like stack.

3 . The method of claim 1 , wherein the second sacrificial layer is sandwiched between the first and third sacrificial layers.

4 . The method of claim 1 , wherein the first sacrificial layer is made of a first material, the second sacrificial layer is made of a second material, and the third sacrificial layer is made of a third material, the first, second, and third materials are different from each other.

5 . The method of claim 1 , wherein the first sacrificial layer is made of a semiconductor material comprising silicon, germanium, silicon germanium, silicon carbide, silicon germanium carbide, germanium-tin, silicon-tin, silicon germanium-tin, gallium arsenide, indium gallium arsenide, indium arsenide, indium phosphide, indium antimonide, gallium arsenic phosphide, gallium indium phosphide, or combinations thereof.

6 . The method of claim 5 , wherein the first sacrificial layer is made of a dielectric material comprising silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon oxycarbide, or combinations thereof.

7 . The method of claim 1 , wherein the first dielectric layer is made of a high-k dielectric material.

8 . The method of claim 1 , wherein the first dielectric layer, the second dielectric layer, or the third dielectric layer is a multilayer structure, and the first electrode material, the second electrode material, or the third electrode material is a multilayer structure.

9 . The method of claim 1 , further comprises:

forming a fourth sacrificial layer vertically stacked on the third sacrificial layer;

removing the fourth sacrificial layer to form a fourth space; and

depositing a fourth dielectric layer and a fourth electrode material in the fourth space.

10 . The method of claim 1 , further comprises:

forming metallization layers on the substrate prior to forming the sacrificial multi-layer stack.

11 . A method, comprising:

forming a sacrificial multi-layer stack including a plurality of sacrificial layers stacked in a vertical direction on a substrate;

depositing a dielectric material over the sacrificial multi-layer stack;

etching the dielectric material to form a first trench exposing a first side of the sacrificial multi-layer stack, wherein the first trench has a maximum dimension extending in a first direction from a top view;

removing a first one of the sacrificial layers exposed by the first trench to form a first space communicating with the first trench;

depositing a first high-k dielectric layer and a first electrode material in the first trench and the first space;

etching the dielectric material to form a second trench exposing a second side of the sacrificial multi-layer stack, wherein the second trench has a maximum dimension extending in a second direction perpendicular to the first direction from the top view;

removing a second one of the sacrificial layers exposed by the second trench to form a second space communicating with the second trench; and

forming a second electrode material in the second trench and the second space.

12 . The method of claim 11 , further comprising:

before forming the second electrode material, conformally depositing a second high-k dielectric layer in the second trench and the second space.

13 . The method of claim 11 , further comprising:

etching the dielectric material to form a third trench exposing a third side of the sacrificial multi-layer stack opposite to the first side of the sacrificial multi-layer stack;

removing a third one of the sacrificial layers exposed by the third trench to form a third space communicating with the third trench; and

forming a third electrode material in the third trench and the third space.

14 . The method of claim 11 , wherein the first high-k dielectric layer comprises hafnium oxide, hafnium silicon oxide, hafnium silicon oxynitride, hafnium tantalum oxide, hafnium titanium oxide, hafnium zirconium oxide, lanthanum oxide, zirconium oxide, titanium oxide, tantalum oxide, yttrium oxide, strontium titanium oxide, barium titanium oxide, barium zirconium oxide, hafnium lanthanum oxide, lanthanum silicon oxide, aluminum silicon oxide, aluminum oxide, silicon nitride, oxynitride, or combinations thereof.

15 . The method of claim 11 , wherein the first electrode material comprises tungsten, titanium aluminide, titanium aluminium nitride, carbo-nitride tantalum, hafnium, zirconium, titanium, tantalum, aluminum, hafnium carbide, zirconium carbide, titanium carbide, aluminum carbide, aluminide, titanium nitride, tungsten nitride, copper, ruthenium, ruthenium oxide, palladium, platinum, cobalt, nickel, argentum, Aurum, or combinations thereof.

16 . A method, comprising:

forming a first capacitor over a substrate, the first capacitor comprising:

a first electrode comprising a first vertical portion and a first lateral portion laterally extending from the first vertical portion; and

a second electrode spaced apart from the first electrode and comprising a second vertical portion and a second lateral portion laterally extending from the second vertical portion, wherein a bottom surface of the second vertical portion of the second electrode is lower than a bottom surface of the first lateral portion of the first electrode; and

forming a second capacitor over the substrate, the second capacitor comprising:

the second electrode; and

a third electrode spaced apart from the first and second electrodes and comprising a third vertical portion and a third lateral portion laterally extending from the third vertical portion,

wherein the second lateral portion of the second electrode is sandwiched between the first lateral portion of the first electrode and the third lateral portion of the third electrode.

17 . The method of claim 16 , further comprising:

forming a third capacitor over the substrate, the third capacitor comprising the third electrode and a fourth electrode, the fourth electrode spaced apart from the first, second, and third electrodes, and comprising:

a fourth vertical portion on the substrate; and

a fourth lateral portion laterally extending from the fourth vertical portion and vertically stacked with the first, second, and third lateral portions of the first, second, and third electrodes.

18 . The method of claim 16 , further comprising:

forming an insulator such that the insulator interposes the first, second, and third electrodes.

19 . The method of claim 18 , wherein the insulator is made of a high-k dielectric material.

20 . The method of claim 16 , further comprising:

forming a plurality of metal lines and a plurality of metal vias alternating arranged in a direction perpendicular to a top surface of the substrate, wherein the metal lines and the metal vias are arranged in a position above a bottom surface of the first electrode and below a top surface of the first electrode.