US6716687B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
FET having epitaxial silicon growth
Assignee: Round Rock Research LLC
•
Filing: 2002-02-11
•
Granted: 2004-04-06
•
Expires: 2022-02-11
Abstract
Abstract Field-effect transistors, and methods of their fabrication, having channel regions formed separately from their source/drain regions and having monocrystalline material interposed between the channel regions and the source/drain regions. The monocrystalline material includes monocrystalline silicon and silicon-germanium alloy.
Inventors
- 👤 Zhongze Wang
- 👤 Chih-Chen Cho
- 👤 Er-Xuan Ping
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:44
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/027; H10D30/0278; H10D62/00; H10D62/10; H10D62/113; H10D62/115; H10D62/116; H10P; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10W; H10W10/00; H10W10/01; H10W10/061; H10W10/10; H10W10/181
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
90 words
A method of forming a field-effect transistor, comprising: forming a channel region within a bulk semiconductor material of a semiconductor substrate, wherein the channel region comprises a first monocrystalline material; exposing a portion of the first monocrystalline material to a surface of the semiconductor substrate; performing an epitaxial deposition upon the exposed portion of the first monocrystalline material, thereby forming extensions of second monocrystalline material; and forming source/drain regions on opposing sides of the channel region, wherein the source/drain regions are in contact with the extensions of second monocrystalline material.
Claim 2
Independent Claim
90 words
A method of forming a field-effect transistor, comprising: forming a channel region within a bulk semiconductor material of a semiconductor substrate, wherein the channel region comprises a first monocrystalline material; exposing a portion of the first monocrystalline material to a surface of the semiconductor substrate; performing an epitaxial deposition upon the exposed portion of the first monocrystalline material, thereby forming extensions of second monocrystalline material; and forming source/drain regions on opposing sides of the channel region, wherein the source/drain regions are in contact with the extensions of second monocrystalline material.
Claim 3
Dependent Claim
18 words
The method of claim 1 , wherein the first epitaxial monocrystalline material is a doped monocrystalline silicon material.
Claim 4
Dependent Claim
18 words
The method of claim 2 , wherein the second epitaxial monocrystalline material is a doped monocrystalline silicon material.
Claim 5
Dependent Claim
15 words
The method of claim 2 , wherein the second monocrystalline material is a silicon-germanium alloy.
Claim 6
Dependent Claim
17 words
The method of claim 4 , wherein the silicon-germanium alloy comprises between approximately 20-50 at % germanium.
Claim 7
Dependent Claim
24 words
The method of claim 1 , wherein performing an epitaxial deposition further comprises performing an epitaxial deposition in the presence of a dopant material.
Claim 8
Dependent Claim
15 words
The method of claim 6 , wherein the dopant material is a conductivity enhancing material.
Claim 9
Dependent Claim
12 words
The method of claim 6 , wherein the dopant material is germanium.
Claim 10
Dependent Claim
19 words
The method of claim 1 , wherein forming source/drain regions further comprises forming source/drain regions of a polycrystalline material.
Claim 11
Dependent Claim
13 words
The method of claim 9 , wherein the polycrystalline material is polycrystalline silicon.
Claim 12
Dependent Claim
27 words
The method of claim 10 , wherein the polycrystalline silicon is doped to have a conductivity type opposite of a conductivity type of the bulk semiconductor substrate.
Claim 13
Independent Claim
24 words
A method of forming a field-effect transistor, comprising: forming extensions of epitaxial monocrystalline material extending away from a channel region of the field-effect transistor.
Claim 14
Independent Claim
24 words
A method of forming a field-effect transistor, comprising: forming extensions of epitaxial monocrystalline material extending away from a channel region of the field-effect transistor.
Claim 15
Dependent Claim
20 words
The method of claim 12 , wherein forming extensions of epitaxial monocrystalline material further comprises forming extensions of epitaxial silicon.
Claim 16
Dependent Claim
20 words
The method of claim 13 , wherein forming extensions of epitaxial silicon further comprises forming extensions of doped epitaxial silicon.
Claim 17
Dependent Claim
15 words
The method of claim 14 , wherein the doped epitaxial silicon is doped with germanium.
Claim 18
Dependent Claim
21 words
The method of claim 12 , wherein forming extensions of monocrystalline material further comprises forming extensions of epitaxially grown silicon-germanium alloy.
Claim 19
Dependent Claim
18 words
The method of claim 16 , wherein the silicon-germanium alloy comprises approximately 20 at % germanium or more.
Claim 20
Dependent Claim
20 words
The method of claim 17 , wherein the silicon-germanium alloy further comprises no more than approximately 50 at % germanium.
Claim 21
Independent Claim
37 words
A method of forming a field-effect transistor, comprising: forming extensions of epitaxial monocrystalline silicon interposed between a polycrystalline portion of silicon source/drain regions of the field-effect transistor and a monocrystalline silicon channel region of the field-effect transistor.
Claim 22
Independent Claim
37 words
A method of forming a field-effect transistor, comprising: forming extensions of epitaxial monocrystalline silicon interposed between a polycrystalline portion of silicon source/drain regions of the field-effect transistor and a monocrystalline silicon channel region of the field-effect transistor.
Claim 23
Dependent Claim
20 words
The method of claim 19 , wherein forming extensions of epitaxial monocrystalline silicon further comprises performing an epitaxial silicon deposition.
Claim 24
Dependent Claim
26 words
The method or claim 20 , wherein performing an epitaxial silicon deposition further comprises performing an epitaxial silicon deposition in the presence of a dopant gas.
Claim 25
Independent Claim
37 words
A method of forming a field-effect transistor, comprising: forming extensions of epitaxial silicon-germanium alloy interposed between a polycrystalline portion of silicon source/drain regions of the field-effect transistor and a monocrystalline silicon channel region of the field-effect transistor.
Claim 26
Independent Claim
37 words
A method of forming a field-effect transistor, comprising: forming extensions of epitaxial silicon-germanium alloy interposed between a polycrystalline portion of silicon source/drain regions of the field-effect transistor and a monocrystalline silicon channel region of the field-effect transistor.
Claim 27
Dependent Claim
23 words
The method of claim 22 , wherein forming extensions of epitaxial silicon-germanium alloy further comprises performing an epitaxial growth of the silicon-germanium alloy.
Claim 28
Independent Claim
56 words
A method of forming a field-effect transistor, comprising: performing an epitaxial silicon growth subsequent to forming a channel region of the field-effect transistor and prior to forming source/drain regions of the field-effect transistor; wherein the epitaxial silicon is grown on exposed portions of monocrystalline silicon to form the epitaxial silicon extending away from the channel region.
Claim 29
Independent Claim
56 words
A method of forming a field-effect transistor, comprising: performing an epitaxial silicon growth subsequent to forming a channel region of the field-effect transistor and prior to forming source/drain regions of the field-effect transistor; wherein the epitaxial silicon is grown on exposed portions of monocrystalline silicon to form the epitaxial silicon extending away from the channel region.
Claim 30
Independent Claim
61 words
A method of forming a field-effect transistor, comprising: performing an epitaxial growth of silicon-germanium alloy subsequent to forming a channel region of the field-effect transistor and prior to forming source/drain regions of the field-effect transistor; wherein the epitaxial growth of silicon-germanium alloy is grown on exposed portions of monocrystalline silicon to form the silicon-germanium alloy extending away from the channel region.
Claim 31
Independent Claim
61 words
A method of forming a field-effect transistor, comprising: performing an epitaxial growth of silicon-germanium alloy subsequent to forming a channel region of the field-effect transistor and prior to forming source/drain regions of the field-effect transistor; wherein the epitaxial growth of silicon-germanium alloy is grown on exposed portions of monocrystalline silicon to form the silicon-germanium alloy extending away from the channel region.
Claim 32
Independent Claim
61 words
A method of forming a field-effect transistor, comprising: forming a region of monocrystalline silicon to define a channel region; exposing a portion of the region of monocrystalline silicon; growing epitaxial monocrystalline silicon from the exposed portion of the region of monocrystalline silicon; and forming a region of polycrystalline silicon in contact with the epitaxial monocrystalline silicon to define a source/drain region.
Claim 33
Independent Claim
61 words
A method of forming a field-effect transistor, comprising: forming a region of monocrystalline silicon to define a channel region; exposing a portion of the region of monocrystalline silicon; growing epitaxial monocrystalline silicon from the exposed portion of the region of monocrystalline silicon; and forming a region of polycrystalline silicon in contact with the epitaxial monocrystalline silicon to define a source/drain region.
Claim 34
Independent Claim
61 words
A method of forming a field-effect transistor, comprising: forming a region of monocrystalline silicon to define a channel region; exposing a portion of the region of monocrystalline silicon; growing epitaxial silicon-germanium alloy from the exposed portion of the region of monocrystalline silicon; and forming a region of polycrystalline silicon in contact with the epitaxial silicon-germanium alloy to define a source/drain region.
Claim 35
Independent Claim
61 words
A method of forming a field-effect transistor, comprising: forming a region of monocrystalline silicon to define a channel region; exposing a portion of the region of monocrystalline silicon; growing epitaxial silicon-germanium alloy from the exposed portion of the region of monocrystalline silicon; and forming a region of polycrystalline silicon in contact with the epitaxial silicon-germanium alloy to define a source/drain region.
Claim 36
Independent Claim
149 words
A method of forming a field-effect transistor, comprising: forming a first trench in a bulk semiconductor substrate on a first side of a channel region within the bulk semiconductor substrate; forming a second trench in the bulk semiconductor substrate on a second side of the channel region within the bulk semiconductor substrate; forming a layer of dielectric material within each trench; removing a portion of the layer of dielectric material to define a first source/drain void in the first trench and a second source/drain void in the second trench and to expose a portion of the bulk semiconductor substrate in each source/drain void; forming extensions of epitaxial monocrystalline material on the exposed portions of the bulk semiconductor substrate in each source/drain void; forming source/drain semiconductive material within each source/drain void and to be in contact with the extensions of monocrystalline material; and forming a gate over the channel region.
Claim 37
Independent Claim
149 words
A method of forming a field-effect transistor, comprising: forming a first trench in a bulk semiconductor substrate on a first side of a channel region within the bulk semiconductor substrate; forming a second trench in the bulk semiconductor substrate on a second side of the channel region within the bulk semiconductor substrate; forming a layer of dielectric material within each trench; removing a portion of the layer of dielectric material to define a first source/drain void in the first trench and a second source/drain void in the second trench and to expose a portion of the bulk semiconductor substrate in each source/drain void; forming extensions of epitaxial monocrystalline material on the exposed portions of the bulk semiconductor substrate in each source/drain void; forming source/drain semiconductive material within each source/drain void and to be in contact with the extensions of monocrystalline material; and forming a gate over the channel region.
Claim 38
Dependent Claim
44 words
The method of claim 28 , wherein forming extensions of epitaxial monocrystalline material on the exposed portions of the bulk semiconductor substrate in each source/drain void further comprises growing epitaxial silicon on the exposed portions of the bulk semiconductor substrate in each source/drain void.
Claim 39
Dependent Claim
16 words
The method of claim 29 , wherein growing epitaxial silicon further comprises growing undoped epitaxial silicon.
Claim 40
Dependent Claim
44 words
The method of claim 28 , wherein forming extensions of monocrystalline material on the exposed portions of the bulk semiconductor substrate in each source/drain void further comprises growing epitaxial silicon-germanium alloy on the exposed portions of the bulk semiconductor substrate in each source/drain void.
Claim 41
Independent Claim
149 words
A method of forming a field-effect transistor, comprising: forming a first trench in a monocrystalline silicon substrate on a first side of a channel region within the monocrystalline silicon substrate; forming a second trench in the monocrystalline silicon substrate on a second side of the channel region within the monocrystalline silicon substrate; forming a layer of dielectric material within each trench; removing a portion of the layer of dielectric material to define a first source/drain void in the first trench and a second source/drain void in the second trench and to expose a portion of the monocrystalline silicon substrate in each source/drain void; forming extensions of epitaxial monocrystalline silicon on the exposed portions of the monocrystalline silicon substrate in each source/drain void; and forming polycrystalline silicon within each source/drain void and to be in contact with the extensions of monocrystalline silicon; and forming a gate over the channel region.
Claim 42
Independent Claim
149 words
A method of forming a field-effect transistor, comprising: forming a first trench in a monocrystalline silicon substrate on a first side of a channel region within the monocrystalline silicon substrate; forming a second trench in the monocrystalline silicon substrate on a second side of the channel region within the monocrystalline silicon substrate; forming a layer of dielectric material within each trench; removing a portion of the layer of dielectric material to define a first source/drain void in the first trench and a second source/drain void in the second trench and to expose a portion of the monocrystalline silicon substrate in each source/drain void; forming extensions of epitaxial monocrystalline silicon on the exposed portions of the monocrystalline silicon substrate in each source/drain void; and forming polycrystalline silicon within each source/drain void and to be in contact with the extensions of monocrystalline silicon; and forming a gate over the channel region.
References Cited (Backward Citations)
US5908313A
Cited
US6156589A
Cited
US6274913B1
Cited
US6180494B1
Cited
US6391726B1
Cited
US6388294B1
Cited
US6300219B1
Cited
US6358798B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-04-06 | 2007-10-06 | 2008-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-04-06 | 2011-10-06 | 2012-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-04-06 | 2015-10-06 | 2016-04-06 | $7700.00 | Window Closed / Lapsed |