US6531354B2
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Lanthanum oxide-based gate dielectrics for integrated circuit field effect transistors
Assignee: North Carolina State University
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Filing: 2001-01-17
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Granted: 2003-03-11
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Expires: 2021-01-17
Abstract
Abstract Lanthanum oxide-based gate dielectrics are provided for integrated circuit field effect transistors. The gate dielectrics may include lanthanum oxide, preferably amorphous lanthanum oxide and/or an alloy of lanthanum oxide and silicon oxide, such as lanthanum silicate (La 2 SiO 5 ). Lanthanum oxide-based gate dielectrics may be fabricated by evaporating lanthanum on a silicon surface of an integrated circuit substrate. The lanthanum may be evaporated in the presence of oxygen. Lanthanum and silicon may be co-evaporated. An anneal then may be performed. Lanthanum oxide-based dielectrics also may be used for integrated circuit capacitors.
Inventors
- 👤 Jon-Paul Maria
- 👤 Angus Ian Kingon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:54
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6921; H10P14/6928; H10P14/6933; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/0134; H10D64/01342; H10D64/01352; H10D64/60; H10D64/66; H10D64/68; H10D64/681; H10D64/685; H10D64/691; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/05; H10D1/00; H10D1/60; H10D1/68; H10D1/682; H10D1/684; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6308; H10P14/6309; H10P14/6322; H10P14/6326; H10P14/6328; H10P14/6332; H10P14/6334; H10P14/6336; H10P14/6922; H10P14/6927; H10P14/6938; H10P14/6939; H10P14/69396
Claims Analysis
Total Claims: 40
Claim 1
Independent Claim
26 words
A gate dielectric for an integrated circuit field effect transistor, the gate dielectric comprising: an amorphous layer comprising an alloy of lanthanum oxide and silicon oxide.
Claim 2
Dependent Claim
26 words
A gate dielectric for an integrated circuit field effect transistor, the gate dielectric comprising: an amorphous layer comprising an alloy of lanthanum oxide and silicon oxide.
Claim 3
Dependent Claim
37 words
A gate dielectric according to claim 1 wherein the amorphous layer comprising an alloy of lanthanum oxide and silicon oxide comprises: a layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x , where 0<x≦1.
Claim 4
Dependent Claim
10 words
A gate dielectric according to claim 2 , where 0.01<x≦1.
Claim 5
Dependent Claim
10 words
A gate dielectric according to claim 2 , where 0.5<x≦1.
Claim 6
Dependent Claim
10 words
A gate dielectric according to claim 2 , where x=0.5.
Claim 7
Dependent Claim
37 words
A gate dielectric according to claim 2 wherein the layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x comprises a uniform layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x .
Claim 8
Dependent Claim
59 words
A gate dielectric according to claim 2 wherein the layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x comprises: a first sublayer comprising (La 2 O 3 ) x1 (SiO 2 ) 1−x1 ; and a second sublayer comprising (La 2 O 3 ) x2 (SiO 2 ) 1−x2 ; where x 1 ≦x 2 .
Claim 9
Dependent Claim
93 words
A gate dielectric for an integrated circuit field effect transistor, the gate dielectric comprising: a first sublayer comprising (La 2 O 3 ) x1 (SiO 2 ) 1−x1 ; a second sublayer comprising (La 2 O 3 ) x2 (SiO 2 ) 1−x2 on the first sublayer, where x 1 ≦x 2 ; and a third sublayer comprising (La 2 O 3 ) x3 (SiO 2 ) 1−x3 on the second sublayer, opposite the first sublayer, where x 3 ≦x 2 , and where 0<x 1 , x 2 , x 3 ≦1.
Claim 10
Dependent Claim
93 words
A gate dielectric for an integrated circuit field effect transistor, the gate dielectric comprising: a first sublayer comprising (La 2 O 3 ) x1 (SiO 2 ) 1−x1 ; a second sublayer comprising (La 2 O 3 ) x2 (SiO 2 ) 1−x2 on the first sublayer, where x 1 ≦x 2 ; and a third sublayer comprising (La 2 O 3 ) x3 (SiO 2 ) 1−x3 on the second sublayer, opposite the first sublayer, where x 3 ≦x 2 , and where 0<x 1 , x 2 , x 3 ≦1.
Claim 11
Dependent Claim
27 words
A gate dielectric according to claim 1 in combination with a capacitor dielectric for an integrated circuit capacitor, the capacitor dielectric comprising a layer comprising lanthanum oxide.
Claim 12
Dependent Claim
71 words
A field effect transistor comprising: spaced apart source and drain regions in an integrated circuit substrate; and an insulated gate on the integrated circuit substrate, the insulated gate comprising a gate dielectric amorphous layer comprising an alloy of lanthanum oxide and silicon oxide on the integrated circuit substrate and a gate electrode on the gate dielectric amorphous layer comprising an alloy of lanthanum oxide and silicon oxide, opposite the integrated circuit.
Claim 13
Dependent Claim
71 words
A field effect transistor comprising: spaced apart source and drain regions in an integrated circuit substrate; and an insulated gate on the integrated circuit substrate, the insulated gate comprising a gate dielectric amorphous layer comprising an alloy of lanthanum oxide and silicon oxide on the integrated circuit substrate and a gate electrode on the gate dielectric amorphous layer comprising an alloy of lanthanum oxide and silicon oxide, opposite the integrated circuit.
Claim 14
Dependent Claim
42 words
A field effect transistor according to claim 10 wherein the gate dielectric amorphous layer comprising an alloy of lanthanum oxide and silicon oxide comprises: a gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x , where 0<x≦1.
Claim 15
Dependent Claim
11 words
A field effect transistor according to claim 11 , where 0.01<x≦1.
Claim 16
Dependent Claim
11 words
A field effect transistor according to claim 11 , where 0.5<x≦1.
Claim 17
Dependent Claim
11 words
A field effect transistor according to claim 11 , where x=0.5.
Claim 18
Dependent Claim
42 words
A field effect transistor according to claim 11 wherein the gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x comprises a uniform gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x .
Claim 19
Dependent Claim
72 words
A field effect transistor according to claim 11 wherein the gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x comprises: a first sublayer comprising (La 2 O 3 ) x1 (SiO 2 ) 1−x1 , adjacent the integrated circuit substrate; and a second sublayer comprising (La 2 O 3 ) x2 (SiO 2 ) 1−x2 , opposite the integrated circuit substrate; where x 1 ≦x 2 .
Claim 20
Dependent Claim
176 words
A field effect transistor comprising: spaced apart source and drain regions in an integrated circuit substrate; and an insulated gate on the integrated circuit substrate, the insulated gate comprising a gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide on the integrated circuit substrate and a gate electrode on the gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide, opposite the integrated circuit; wherein the gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x comprises: a first sublayer comprising (La 2 O 3 ) x1 (SiO 2 ) 1−x1 , adjacent the integrated circuit substrate; a second sublayer comprising (La 2 O 3 ) x2 (SiO 2 ) 1−x2 , on the first sublayer opposite the integrated circuit substrate, where x 1 ≦x 2 ; and a third sublayer comprising (La 2 O 3 ) x3 (SiO 2 ) 1−x3 on the second sublayer, opposite the first sublayer, where x 3 ≦x 2 , and where 0<x 1 , x 2 , x 3 ≦1.
Claim 21
Dependent Claim
176 words
A field effect transistor comprising: spaced apart source and drain regions in an integrated circuit substrate; and an insulated gate on the integrated circuit substrate, the insulated gate comprising a gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide on the integrated circuit substrate and a gate electrode on the gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide, opposite the integrated circuit; wherein the gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x comprises: a first sublayer comprising (La 2 O 3 ) x1 (SiO 2 ) 1−x1 , adjacent the integrated circuit substrate; a second sublayer comprising (La 2 O 3 ) x2 (SiO 2 ) 1−x2 , on the first sublayer opposite the integrated circuit substrate, where x 1 ≦x 2 ; and a third sublayer comprising (La 2 O 3 ) x3 (SiO 2 ) 1−x3 on the second sublayer, opposite the first sublayer, where x 3 ≦x 2 , and where 0<x 1 , x 2 , x 3 ≦1.
Claim 22
Dependent Claim
33 words
A field effect transistor according to claim 10 wherein the gate electrode comprises at least one of polysilicon, TaN, Pt, Ru, RuO, Ir, IrO 2 and Ta 1−x Si x N y .
Claim 23
Dependent Claim
41 words
A field effect transistor according to claim 10 wherein the field effect transistor is an n-channel field effect transistor and wherein the gate electrode comprises at least one of polysilicon, TaN, Ta 1−x Si x N y and IrO 2 .
Claim 24
Dependent Claim
38 words
A field effect transistor according to claim 10 wherein the field effect transistor is a p-channel field effect transistor and wherein the gate electrode comprises at least one of polysilicon, Pt, Ru, RuO, Ir and IrO 2 .
Claim 25
Dependent Claim
39 words
A field effect transistor according to claim 10 in combination with a capacitor on the integrated circuit substrate, the capacitor comprising first and second electrodes and a capacitor dielectric therebetween, the capacitor dielectric comprising a layer comprising lanthanum oxide.
Claim 26
Dependent Claim
79 words
An integrated circuit complementary field effect transistor pair comprising: an n-channel insulated gate field effect transistor and a p-channel insulated gate field effect transistor in an integrated circuit substrate, each of which comprises an insulated gate including a gate dielectric amorphous layer comprising an alloy of lanthanum oxide and silicon oxide on the integrated circuit substrate and a gate electrode on the gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide, opposite the integrated circuit substrate.
Claim 27
Dependent Claim
79 words
An integrated circuit complementary field effect transistor pair comprising: an n-channel insulated gate field effect transistor and a p-channel insulated gate field effect transistor in an integrated circuit substrate, each of which comprises an insulated gate including a gate dielectric amorphous layer comprising an alloy of lanthanum oxide and silicon oxide on the integrated circuit substrate and a gate electrode on the gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide, opposite the integrated circuit substrate.
Claim 28
Dependent Claim
45 words
An integrated circuit complementary field effect transistor according to claim 22 wherein the gate dielectric amorphous layer comprising an alloy of lanthanum oxide and silicon oxide comprises: a gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x , where 0<x≦1.
Claim 29
Dependent Claim
14 words
An integrated circuit complementary field effect transistor according to claim 23 , where 0.01<x≦1.
Claim 30
Dependent Claim
15 words
An integrated circuit complementary field effect transistor pair according to claim 23 , where 0.5<x≦1.
Claim 31
Dependent Claim
15 words
An integrated circuit complementary field effect transistor pair according to claim 23 , where x=0.5.
Claim 32
Dependent Claim
174 words
An integrated circuit complementary field effect transistor pair comprising: an n-channel insulated gate field effect transistor and a p-channel insulated gate field effect transistor in an integrated circuit substrate, each of which comprises an insulated gate including a gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide on the integrated circuit substrate and a gate electrode on the gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide, opposite the integrated circuit substrate; wherein the gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x comprises: a first sublayer comprising (La 2 O 3 ) x1 (SiO 2 ) 1−x1 ; a second sublayer comprising (La 2 O 3 ) x2 (SiO 2 ) 1−x2 on the first sublayer, where x 1 ≦x 2 ; and a third sublayer comprising (La 2 O 3 ) x3 (SiO 2 ) 1−x3 on the second sublayer, opposite the first sublayer, where x 3 ≦x 2 , and where 0<x 1 , x 2 , x 3 ≦1.
Claim 33
Dependent Claim
174 words
An integrated circuit complementary field effect transistor pair comprising: an n-channel insulated gate field effect transistor and a p-channel insulated gate field effect transistor in an integrated circuit substrate, each of which comprises an insulated gate including a gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide on the integrated circuit substrate and a gate electrode on the gate dielectric layer comprising an alloy of lanthanum oxide and silicon oxide, opposite the integrated circuit substrate; wherein the gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x comprises: a first sublayer comprising (La 2 O 3 ) x1 (SiO 2 ) 1−x1 ; a second sublayer comprising (La 2 O 3 ) x2 (SiO 2 ) 1−x2 on the first sublayer, where x 1 ≦x 2 ; and a third sublayer comprising (La 2 O 3 ) x3 (SiO 2 ) 1−x3 on the second sublayer, opposite the first sublayer, where x 3 ≦x 2 , and where 0<x 1 , x 2 , x 3 ≦1.
Claim 34
Dependent Claim
66 words
An integrated circuit complementary field effect transistor pair according to claim 23 wherein the gate dielectric layer comprising (La 2 O 3 ) x (SiO 2 ) 1−x comprises: a first sublayer comprising (La 2 O 3 ) x1 (SiO 2 ) 1−x1 ; and a second sublayer comprising (La 2 O 3 ) x2 (SiO 2 ) 1−x2 ; where x 1 ≦x 2 .
Claim 35
Dependent Claim
43 words
An integrated circuit complementary field effect transistor pair according to claim 22 in combination with a capacitor on the integrated circuit substrate, the capacitor comprising first and second electrodes and a capacitor dielectric therebetween, the capacitor dielectric comprising a layer comprising lanthanum oxide.
Claim 36
Dependent Claim
54 words
An integrated circuit complementary field effect transistor pair according to claim 22 wherein the gate electrodes of the n-channel insulated gate field effect transistor and of the p-channel insulated gate field effect transistor comprise at least one of polysilicon, TaN, Pt, Ru, RuO, Ir, IrO 2 and Ta 1−x Si x N y .
Claim 37
Dependent Claim
39 words
An integrated circuit complementary field effect transistor pair according to claim 22 wherein the gate electrode of the n-channel field effect transistor comprises at least one of polysilicon, TaN, Ta 1−x Si x N y and IrO 2 .
Claim 38
Dependent Claim
36 words
An integrated circuit complementary field effect transistor pair according to claim 22 wherein the gate electrode for the p-channel field effect transistor comprises at least one of polysilicon, Pt, Ru, RuO, Ir and IrO 2 .
Claim 39
Dependent Claim
36 words
An integrated circuit complementary field effect transistor pair according to claim 31 wherein the gate electrode for the p-channel field effect transistor comprises at least one of polysilicon, Pt, Ru, RuO, Ir and IrO 2 .
Claim 40
Dependent Claim
43 words
An integrated circuit complementary field effect transistor pair according to claim 22 in combination with a capacitor on the integrated circuit substrate, the capacitor comprising first and second electrodes and a capacitor dielectric therebetween, the capacitor dielectric comprising a layer comprising lanthanum oxide.
References Cited (Backward Citations)
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