US5856696A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Field effect transistor having dielectrically isolated sources and drains
Assignee: STMicroelectronics lnc USA
•
Filing: 1997-03-12
•
Granted: 1999-01-05
•
Expires: 2017-03-12
Abstract
Abstract A field-effect transistor structure is described having a monocrystalline silicon channel region which is epitaxially continuous with an underlying monocrystalline silicon body region. Polycrystalline silicon source and drain regions abut the channel region. The source and drain regions are electrically isolated from the underlying body region by a patterned dielectric layer, which may include a thick field oxide. A polycrystalline silicon gate is capacitively coupled with the channel region by a second dielectric layer. The gate may extend laterally to partly overlap the source and drain regions.
Inventors
- 👤 Richard A. Blanchard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:36
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/027; H10D30/0278; H10D30/031; H10D30/0321; H10D30/0323; H10D30/60; H10D30/67; H10D30/674; H10D30/6741; H10D30/6743; H10D30/6744; H10D30/6758; H10D62/00; H10D62/10; H10D62/113; H10D62/115; H10D62/116; H10D62/17; H10D62/213; H10D62/221; H10D62/235; H10D62/292; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0165; H10D84/0167; H10D84/017; H10D84/02; H10D84/03; H10D84/038; H10D84/80; H10D84/82; H10D84/83; H10D84/85; H10D84/854; H10D86/00; H10D86/01
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
85 words
An integrated circuit field-effect transistor structure, comprising: a monocrystalline semiconductor channel region; a conductive gate capacitively coupled to the channel region; a monocrystalline semiconductor body region which underlies and is epitaxially continuous with the channel region; first and second polycrystalline semiconductor source/drain regions which laterally adjoin opposing sides of the channel region and extend therefrom, the source/drain regions and the channel region residing in a single layer of semiconductor material; and a patterned dielectric layer, which underlies the source/drain regions but not the channel region.
Claim 2
Dependent Claim
85 words
An integrated circuit field-effect transistor structure, comprising: a monocrystalline semiconductor channel region; a conductive gate capacitively coupled to the channel region; a monocrystalline semiconductor body region which underlies and is epitaxially continuous with the channel region; first and second polycrystalline semiconductor source/drain regions which laterally adjoin opposing sides of the channel region and extend therefrom, the source/drain regions and the channel region residing in a single layer of semiconductor material; and a patterned dielectric layer, which underlies the source/drain regions but not the channel region.
Claim 3
Dependent Claim
34 words
The transistor structure of claim 1 wherein the patterned dielectric layer is a first patterned dielectric layer, and wherein the transistor structure further comprises a second patterned dielectric layer which underlies the conductive gate.
Claim 4
Dependent Claim
27 words
The transistor structure of claim 1 wherein the patterned dielectric layer is of a substantially uniform thickness which is less than a thickness of the source/drain regions.
Claim 5
Dependent Claim
15 words
The transistor structure of claim 1 wherein the patterned dielectric layer includes a field oxide.
Claim 6
Dependent Claim
15 words
The transistor structure of claim 1 wherein the monocrystalline semiconductor body region is an N-well.
Claim 7
Dependent Claim
15 words
The transistor structure of claim 1 wherein the monocrystalline semiconductor channel region is monocrystalline silicon.
Claim 8
Dependent Claim
17 words
The transistor structure of claim 1 wherein each of the polycrystalline semiconductor source/drain regions is polycrystalline silicon.
Claim 9
Dependent Claim
73 words
A field-effect transistor, comprising: first and second polycrystalline semiconductor regions of a first conductivity type; a monocrystalline semiconductor region of a second conductivity type located between and laterally adjacent to the first and second polycrystalline semiconductor regions, the monocrystalline semiconductor region and the first and second polycrystalline semiconductor regions being formed in a single continuous semiconductor layer; a dielectric region overlying the monocrystalline semiconductor region; and a conductive region overlying the dielectric layer.
Claim 10
Dependent Claim
73 words
A field-effect transistor, comprising: first and second polycrystalline semiconductor regions of a first conductivity type; a monocrystalline semiconductor region of a second conductivity type located between and laterally adjacent to the first and second polycrystalline semiconductor regions, the monocrystalline semiconductor region and the first and second polycrystalline semiconductor regions being formed in a single continuous semiconductor layer; a dielectric region overlying the monocrystalline semiconductor region; and a conductive region overlying the dielectric layer.
Claim 11
Dependent Claim
32 words
The transistor of claim 8 wherein the dielectric region is a first dielectric region, and wherein the transistor further comprises a second dielectric region underlying the first and second polycrystalline semiconductor regions.
Claim 12
Dependent Claim
19 words
The transistor of claim 9 wherein each of the first and second dielectric regions substantially consist of silicon dioxide.
Claim 13
Dependent Claim
39 words
The transistor of claim 8 wherein the monocrystalline semiconductor region is a first monocrystalline semiconductor region, and wherein the transistor further comprises a second monocrystalline semiconductor region which underlies and is epitaxially continuous with the first monocrystalline semiconductor region.
Claim 14
Dependent Claim
18 words
The transistor of claim 8 wherein each of the first and second polycrystalline semiconductor regions is polycrystalline silicon.
Claim 15
Dependent Claim
21 words
The transistor of claim 8 wherein the conductive region extends laterally to partially overlap the first and second polycrystalline semiconductor regions.
Claim 16
Dependent Claim
18 words
The transistor of claim 8 wherein the first and second polycrystalline semiconductor regions have substantially similar doping profiles.
Claim 17
Dependent Claim
72 words
A field-effect transistor, comprising: a monocrystalline semiconductor body region; a monocrystalline semiconductor channel region which overlies and extends epitaxially from the body region; a conductive gate region capacitively coupled with the channel region; and first and second polycrystalline semiconductor source/drain regions which are electrically isolated from the body region and which laterally adjoin opposite sides of the channel region, the source/drain regions and the channel region being a single contiguous semiconductor layer.
Claim 18
Dependent Claim
72 words
A field-effect transistor, comprising: a monocrystalline semiconductor body region; a monocrystalline semiconductor channel region which overlies and extends epitaxially from the body region; a conductive gate region capacitively coupled with the channel region; and first and second polycrystalline semiconductor source/drain regions which are electrically isolated from the body region and which laterally adjoin opposite sides of the channel region, the source/drain regions and the channel region being a single contiguous semiconductor layer.
Claim 19
Dependent Claim
31 words
The transistor of claim 15, further comprising a dielectric region positioned between each of the source/drain regions and the body region to electrically isolate the source/drain regions from the body region.
Claim 20
Dependent Claim
27 words
The transistor of claim 16 wherein the body region is monocrystalline silicon, the source drain regions are each polycrystalline silicon, and the dielectric region is silicon dioxide.
Claim 21
Dependent Claim
14 words
The transistor of claim 15 wherein the source/drain regions have substantially similar doping profiles.
Claim 22
Dependent Claim
19 words
The transistor of claim 15 wherein at least one of the source/drain regions includes a lightly doped drain region.
Claim 23
Dependent Claim
45 words
The transistor of claim 15 wherein the conductive gate region extends laterally to partially overlap at least one of the source/drain regions, and wherein the source/drain regions are more lightly doped where underlying the conductive gate region than where not underlying the conductive gate region.
References Cited (Backward Citations)
US4041518A
Cited
US4353085A
Cited
US4609407A
Cited
JPS56115557A
Cited
US4487639A
Cited
US4651408A
Cited
US5213991A
Cited
US4874716A
Cited
US4862232A
Cited
US4966861A
Cited
EP0267082A1
Cited
US4879255A
Cited
US4914053A
Cited
US5132755A
Cited
US5338697A
Cited
US5110757A
Cited
US5422303A
Cited
US5498567A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-01-04 | 2002-07-06 | 2003-01-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-01-04 | 2006-07-06 | 2007-01-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-01-04 | 2010-07-06 | 2011-01-05 | $7700.00 | Window Closed / Lapsed |