US7271055B2
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Methods of forming low leakage currents metal-insulator-metal (MIM) capacitors and related MIM capacitors
Assignee: Samsung Electronics Co Ltd
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Filing: 2005-08-12
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Granted: 2007-09-18
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Expires: 2025-08-12
Abstract
Abstract Methods of forming MIM comprise forming a lower electrode on a semiconductor substrate, forming a lower dielectric layer on the lower electrode, and forming an upper dielectric layer on the lower dielectric layer. The lower dielectric layer may be formed of dielectrics having larger energy band gap than that of the upper dielectric layer. An upper electrode is formed on the upper dielectric layer. The upper electrode may be formed of a metal layer having a higher work function than that of the lower electrode.
Inventors
- 👤 Kwang-Hee Lee
- 👤 Jin-Yong Kim
- 👤 Suk-Jin Chung
- 👤 Kyu-Ho Cho
- 👤 Han-jin Lim
- 👤 Jin-Il Lee
- 👤 Ki-chul Kim
- 👤 Jae-soon Lim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:16
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/66; H10P14/662; H10D; H10D1/00; H10D1/60; H10D1/68; H10D1/682; H10D1/684; H10P14/68; H10P14/69; H10P14/692; H10P14/6938; H10D1/692; H10D1/711; H10D1/716; H10D84/00; H10D84/201; H10D84/204; H10D84/212
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
127 words
A method of forming a capacitor comprising: forming a lower electrode on a semiconductor substrate; forming a lower dielectric layer having a thickness of about 20 to 40 Angstroms on the lower electrode; forming an upper dielectric layer having a thickness of about 10 to 60 Angstroms on the lower dielectric layer, wherein a dielectric constant of the upper dielectric layer is greater than a dielectric constant of the lower dielectric layer, and wherein the energy band gap of the upper dielectric layer is smaller than the energy band gap of the lower dielectric layer; and forming an upper electrode on the upper dielectric layer, wherein the upper electrode comprises a noble metal that has a higher work function than a work function of the lower electrode.
Claim 2
Independent Claim
127 words
A method of forming a capacitor comprising: forming a lower electrode on a semiconductor substrate; forming a lower dielectric layer having a thickness of about 20 to 40 Angstroms on the lower electrode; forming an upper dielectric layer having a thickness of about 10 to 60 Angstroms on the lower dielectric layer, wherein a dielectric constant of the upper dielectric layer is greater than a dielectric constant of the lower dielectric layer, and wherein the energy band gap of the upper dielectric layer is smaller than the energy band gap of the lower dielectric layer; and forming an upper electrode on the upper dielectric layer, wherein the upper electrode comprises a noble metal that has a higher work function than a work function of the lower electrode.
Claim 3
Dependent Claim
16 words
The method according to claim 1 , wherein the lower electrode comprises a metal nitride layer.
Claim 4
Dependent Claim
57 words
The method according to claim 2 , wherein the metal nitride layer comprises at least one of a titanium nitride (TiN) layer, a titanium silicon nitride (TiSiN) layer, a titanium aluminum nitride (TiAlN) layer, a tantalum nitride (TaN) layer, a tantalum silicon nitride (TaSiN) layer, a tantalum aluminum nitride (TaAlN) layer, and/or a tungsten nitride (WN) layer.
Claim 5
Dependent Claim
26 words
The method according to claim 1 , the method further comprising oxidizing at least some portions of the lower electrode before forming the lower dielectric layer.
Claim 6
Dependent Claim
28 words
The method according to claim 4 , wherein oxidizing at least some portions of the lower electrode comprises performing a rapid thermal oxidation process on the lower electrode.
Claim 7
Dependent Claim
39 words
The method according to claim 5 , wherein the rapid thermal oxidation process is performed for about 10 to 300 seconds at a temperature of about 300 to 550° C. with a pressure of about 0.1 to 760 torr.
Claim 8
Dependent Claim
28 words
The method according to claim 1 , wherein forming the lower electrode comprises forming a lower electrode having a stack structure, a cylinder structure, or a concave structure.
Claim 9
Dependent Claim
50 words
The method according to claim 1 , wherein the lower dielectric layer comprises at least one of a hafnium oxide (HfO 2 ) layer, a zirconium oxide (ZrO 2 ) layer, an aluminum oxide (Al 2 O 3 ) layer, and/or a lanthanum oxide (La 2 O 3 ) layer.
Claim 10
Dependent Claim
28 words
The method according to claim 1 , the method further comprising performing an ammonia plasma treatment process on the lower dielectric layer before forming the upper dielectric layer.
Claim 11
Dependent Claim
41 words
The method according to claim 9 , wherein the ammonia plasma treatment process is performed using a power of about 250 to 350 W at a temperature of about 400° C. or lower and with a pressure of about 2 torr.
Claim 12
Dependent Claim
27 words
The method according to claim 1 , the method further comprising forming an intermediate dielectric layer on the lower dielectric layer before forming the upper dielectric layer.
Claim 13
Dependent Claim
51 words
The method according to claim 11 , wherein the intermediate dielectric layer comprises at least one of a HfO 2 layer, a ZrO 2 layer, an Al 2 O 3 layer, a La 2 O 3 layer, a Ta 2 O 5 layer, a TiO 2 layer, and/or an STO layer.
Claim 14
Dependent Claim
31 words
The method according to claim 1 , wherein the upper dielectric layer comprises at least one of a Ta 2 O 5 layer, a TiO 2 layer, and/or an STO layer.
Claim 15
Dependent Claim
17 words
The method according to claim 13 , wherein the upper dielectric layer comprises a doped TiO2 layer.
Claim 16
Dependent Claim
56 words
The method according to claim 11 , the method further comprising thermally annealing at least the intermediate dielectric layer in an O 2 , O 3 and/or N 2 O gas atmosphere and/or performing a plasma treatment process using plasma formed from O 2 and/or N 2 O gas on at least the intermediate dielectric layer.
Claim 17
Dependent Claim
56 words
The method according to claim 1 , the method further comprising thermally annealing at least the upper dielectric layer in an O 2 , O 3 and/or N 2 O gas atmosphere and/or performing a plasma treatment process on at least the upper dielectric layer using plasma formed from O 2 and/or N 2 O gas.
Claim 18
Dependent Claim
26 words
The method according to claim 1 , wherein the upper electrode comprises at least one of a Ru layer, an Ir layer, and/or a Pt layer.
Claim 19
Dependent Claim
132 words
An MIM capacitor, comprising: a lower electrode on a semiconductor substrate; a lower dielectric layer having a thickness of about 20 to 40 Angstroms on the lower electrode, the lower dielectric layer having a first dielectric constant and a first energy band gap; an upper dielectric layer having a thickness of about 10 to 60 Angstroms on the lower dielectric layer, the upper dielectric layer having a second dielectric constant and a second energy band gap; wherein the second dielectric constant is higher than the first dielectric constant and the second energy band gap is smaller than the first energy band gap; and an upper electrode on the upper dielectric layer, the upper electrode comprising a noble metal that has a higher work function than a work function of the lower electrode.
Claim 20
Dependent Claim
132 words
An MIM capacitor, comprising: a lower electrode on a semiconductor substrate; a lower dielectric layer having a thickness of about 20 to 40 Angstroms on the lower electrode, the lower dielectric layer having a first dielectric constant and a first energy band gap; an upper dielectric layer having a thickness of about 10 to 60 Angstroms on the lower dielectric layer, the upper dielectric layer having a second dielectric constant and a second energy band gap; wherein the second dielectric constant is higher than the first dielectric constant and the second energy band gap is smaller than the first energy band gap; and an upper electrode on the upper dielectric layer, the upper electrode comprising a noble metal that has a higher work function than a work function of the lower electrode.
Claim 21
Dependent Claim
17 words
The MIM capacitor according to claim 18 , wherein the lower electrode comprises a metal nitride layer.
Claim 22
Dependent Claim
58 words
The MIM capacitor according to claim 19 , wherein the metal nitride layer comprises at least one of a titanium nitride (TiN) layer, a titanium silicon nitride (TiSiN) layer, a titanium aluminum nitride (TiAlN) layer, a tantalum nitride (TaN) layer, a tantalum silicon nitride (TaSiN) layer, a tantalum aluminum nitride (TaAlN) layer, and/or a tungsten nitride (WN) layer.
Claim 23
Dependent Claim
20 words
The MIM capacitor according to claim 18 , wherein at least certain surface portions of the lower electrode are oxidized.
Claim 24
Dependent Claim
51 words
The MIM capacitor according to claim 18 , wherein the lower dielectric layer comprises at least one of a hafnium oxide (HfO 2 ) layer, a zirconium oxide (ZrO 2 ) layer, an aluminum oxide (Al 2 O 3 ) layer, and/or a lanthanum oxide (La 2 O 3 ) layer.
Claim 25
Dependent Claim
24 words
The MIM capacitor according to claim 18 , further comprising an intermediate dielectric layer between the lower dielectric layer and the upper dielectric layer.
Claim 26
Dependent Claim
52 words
The MIM capacitor according to claim 23 , wherein the intermediate dielectric layer comprises at least one of a HfO 2 layer, a ZrO 2 layer, an Al 2 O 3 layer, a La 2 O 3 layer, a Ta 2 O 5 layer, a TiO 2 layer, and/or an STO layer.
Claim 27
Dependent Claim
32 words
The MIM capacitor according to claim 18 , wherein the upper dielectric layer comprises at least one of a Ta 2 O 5 layer, a TiO 2 layer, and/or an STO layer.
Claim 28
Dependent Claim
27 words
The MIM capacitor according to claim 18 , wherein the upper electrode comprises at least one of a Ru layer, an Ir layer, and a Pt layer.
Claim 29
Dependent Claim
114 words
An MIM capacitor, comprising: a lower electrode on a semiconductor substrate; a lower dielectric layer on the lower electrode, the lower dielectric layer having a first dielectric constant and a first energy band gap; an upper dielectric layer on the lower dielectric layer, the upper dielectric layer having a second dielectric constant and a second energy band gap; wherein the second dielectric constant is higher than the first dielectric constant and the second energy band gap is smaller than the first energy band gap; and an upper electrode on the upper dielectric layer, the upper electrode comprising a noble metal that has a higher work function than a work function of the lower electrode.
Claim 30
Dependent Claim
114 words
An MIM capacitor, comprising: a lower electrode on a semiconductor substrate; a lower dielectric layer on the lower electrode, the lower dielectric layer having a first dielectric constant and a first energy band gap; an upper dielectric layer on the lower dielectric layer, the upper dielectric layer having a second dielectric constant and a second energy band gap; wherein the second dielectric constant is higher than the first dielectric constant and the second energy band gap is smaller than the first energy band gap; and an upper electrode on the upper dielectric layer, the upper electrode comprising a noble metal that has a higher work function than a work function of the lower electrode.
Claim 31
Dependent Claim
24 words
The MIM capacitor according to claim 27 , further comprising an intermediate dielectric layer between the lower dielectric layer and the upper dielectric layer.
Claim 32
Dependent Claim
22 words
The MIM capacitor according to claim 28 , wherein the lower dielectric layer has a thickness of about 20 to 40 Angstroms.
Claim 33
Dependent Claim
21 words
The MIM capacitor of claim 29 , wherein the upper dielectric layer has a thickness of about 10 to 60 Angstroms.
Claim 34
Dependent Claim
52 words
The MIM capacitor according to claim 28 , wherein the intermediate dielectric layer comprises at least one of a HfO 2 layer, a ZrO 2 layer, an Al 2 O 3 layer, a La 2 O 3 layer, a Ta 2 O 5 layer, a TiO 2 layer, and/or an STO layer.
References Cited (Backward Citations)
US6586792B2
Cited
KR20030059712A
Cited
KR20030073934A
Cited
KR20030085822A
Cited
KR20040008992A
Cited
US6897106B2
Cited
KR20040020172A
Cited
US20050141168A1
Cited
US7153786B2
Cited
US20050260357A1
Cited
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