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US4748485A Expired / Lapsed US ⏱️ 0.0 years remaining

Opposed dual-gate hybrid structure for three-dimensional integrated circuits

Assignee: The AT&T MVPD Group LLC
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Filing: 1987-06-09
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Granted: 1988-05-31
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Expires: 2007-06-09
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Abstract

Abstract A three-dimensional integrated circuit structure utilizing a hybridization of silicon-on-insulator and silicon-on-sapphire technologies is disclosed, wherein a buried doped epitaxial silicon layer, insulated from a gated semiconductor device by a buried insulating layer, biases the gate region of the overlying semiconductor device, thereby providing a second gate positionally opposed to the conventional first gate of the semiconductor device. The second gate (or backgate) is utilized to draw undesired charge carriers from its overlying insulating layer, thereby avoiding the undesirable effects of the presence of such excess charge carriers, which typically may be induced by external radiation. The selectable backgating feature is fully compatible with existing integrated circuit fabrication technology, and may be utilized to provide a single backgate for all overlying semiconductor devices, or individual backgates for one or groups of semiconductor devices in island-etched structures.

Inventors

  • 👤 Prahalad K. Vasudev

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 14:07
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/6729; H10D30/673; H10D30/6733; H10D30/6734; H10D30/6758; H10D30/6759; H10D86/00; H10D86/01; H10D86/03

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 190 words
A semiconductor integrated circuit device, comprising: an insulating substrate; a first backgate electrode made of a layer of doped semiconductor material epitaxially related to said insulating substrate formed over a portion of said insulating substrate; a second backgate electrode made of a layer of doped semiconductor material epitaxially related to said insulating substrate formed over another portion of said insulating substrate; an insulating overlay made of nonconductive material overlying and epitaxially related to said first and second backgate electrodes; a first gated semiconductor device including source, channel and drain regions overlying said insulating overlay and first backgate electrode wherein the extent of said first backgate electrode along said insulating overlay is greater than the lateral extent of the source, channel and drain regions of said first semiconductor device; a second gated semiconductor device including source, channel and drain regions overlying said insulating overlay and second backgate electrode wherein the extent of said second backgate electrode along said insulating overlay is greater than the lateral extent of the source, channel and drain regions of said second semiconductor device; and separate means for electrically biasing said first and second backgate electrodes independently.
Claim 2
Dependent Claim 190 words
A semiconductor integrated circuit device, comprising: an insulating substrate; a first backgate electrode made of a layer of doped semiconductor material epitaxially related to said insulating substrate formed over a portion of said insulating substrate; a second backgate electrode made of a layer of doped semiconductor material epitaxially related to said insulating substrate formed over another portion of said insulating substrate; an insulating overlay made of nonconductive material overlying and epitaxially related to said first and second backgate electrodes; a first gated semiconductor device including source, channel and drain regions overlying said insulating overlay and first backgate electrode wherein the extent of said first backgate electrode along said insulating overlay is greater than the lateral extent of the source, channel and drain regions of said first semiconductor device; a second gated semiconductor device including source, channel and drain regions overlying said insulating overlay and second backgate electrode wherein the extent of said second backgate electrode along said insulating overlay is greater than the lateral extent of the source, channel and drain regions of said second semiconductor device; and separate means for electrically biasing said first and second backgate electrodes independently.
Claim 3
Dependent Claim 18 words
The device of claim 1, wherein said substrate is selected from the group consisting of sapphire and spinel.
Claim 4
Dependent Claim 44 words
The device of claim 1, wherein said first and second backgate electrodes and said insulating overlay are formed in a single piece of silicon epitaxially related to said insulating substrate, and wherein said backgate electrodes and said insulating overlay are doped with different dopants.
Claim 5
Dependent Claim 26 words
The device of claim 1, wherein said first and second backgate electrodes are doped with a dopant selected from the group consisting of boron and phosphorus.
Claim 6
Dependent Claim 23 words
The device of claim 1, wherein said insulating overlay is doped with a dopant selected from the group consisting of oxygen and nitrogen.
Claim 7
Dependent Claim 15 words
The device of claim 1, wherein said first and second gated semiconductor devices are MOSFETs.
Claim 8
Dependent Claim 239 words
An integrated semiconductor circuit device, comprising: an insulating substrate selected from the group consisting of sapphire and spinel; a first backgate electrode made of a layer of semiconductor material of N+ or P+ conductivity, overlying and epitaxially related to said insulating substrate; a second backgate electrode made of a layer of semiconductor material of N+ or P+ conductivity overlying and epitaxially related to said insulating substrate; a layer of insulating material overlying said first and second backgate electrodes; a first gated semiconductor device having source, drain and channel regions overlying said insulating layer and first backgate electrode, wherein the extent of said first backgate electrode along said insulating layer is greater than the width of said source, drain and channel regions of said first gated semiconductor device; a second gated semiconductor device having source, drain and channel regions overlying said insulating layer and second backgate electrode, wherein the extent of said second backgate electrode along said insulating layer is greater than the width of said source, drain and channel regions of said second gated semiconductor device; a first electrical backgate contact to said first backgate electrode, whereby said first backgate electrode may be electrically biased to act as a second gate for said first semiconductor gated device; and a second electrical backgate contact to said second backgate electrode, whereby said second backgate electrode may be electrically biased to act as a second gate for said second gated semiconductor device.
Claim 9
Dependent Claim 239 words
An integrated semiconductor circuit device, comprising: an insulating substrate selected from the group consisting of sapphire and spinel; a first backgate electrode made of a layer of semiconductor material of N+ or P+ conductivity, overlying and epitaxially related to said insulating substrate; a second backgate electrode made of a layer of semiconductor material of N+ or P+ conductivity overlying and epitaxially related to said insulating substrate; a layer of insulating material overlying said first and second backgate electrodes; a first gated semiconductor device having source, drain and channel regions overlying said insulating layer and first backgate electrode, wherein the extent of said first backgate electrode along said insulating layer is greater than the width of said source, drain and channel regions of said first gated semiconductor device; a second gated semiconductor device having source, drain and channel regions overlying said insulating layer and second backgate electrode, wherein the extent of said second backgate electrode along said insulating layer is greater than the width of said source, drain and channel regions of said second gated semiconductor device; a first electrical backgate contact to said first backgate electrode, whereby said first backgate electrode may be electrically biased to act as a second gate for said first semiconductor gated device; and a second electrical backgate contact to said second backgate electrode, whereby said second backgate electrode may be electrically biased to act as a second gate for said second gated semiconductor device.
Claim 10
Dependent Claim 14 words
The device of claim 7, wherein said gated semiconductor devices are MOS semiconductor devices.
Claim 11
Dependent Claim 63 words
The device of claim 7, wherein said device contains at least two silicon layers arranged in a side-by-side island fashion, each of said silicon layers including its own separate electrical backgate contact with an insulating overlay so that each of said backgate contacts may be electrically biased independently, and each of said two silicon layers has at least one overlying gated semiconductor device.
Claim 12
Dependent Claim 35 words
The device of claim 7, wherein said substrate has a thickness of about 0.25 millimeters, said first and second backgate electrodes are about 0.2 micrometers thick, and said insulating layer is about 0.1 micrometers thick.
Claim 13
Dependent Claim 110 words
An integrated semiconductor circuit device, comprising, an insulating substrate; a plurality of backgate electrodes made of highly doped semiconductor material overlying and epitaxially related to said insulating substrate; a layer of insulating material overlying and epitaxially related to said plurality of backgate electrodes; a plurality of gated semiconductor devices having source, channel and drain regions overlying said insulating layer, respective one of said gated semiconductor devices overlying respective ones of said backgate electrodes, wherein the extent of respective backgate electrodes along said insulating layer is greater than the width of their respective overlying gated semiconductor device source, channel and drain regions; and separate means for biasing each backgate electrode independently.
Claim 14
Dependent Claim 110 words
An integrated semiconductor circuit device, comprising, an insulating substrate; a plurality of backgate electrodes made of highly doped semiconductor material overlying and epitaxially related to said insulating substrate; a layer of insulating material overlying and epitaxially related to said plurality of backgate electrodes; a plurality of gated semiconductor devices having source, channel and drain regions overlying said insulating layer, respective one of said gated semiconductor devices overlying respective ones of said backgate electrodes, wherein the extent of respective backgate electrodes along said insulating layer is greater than the width of their respective overlying gated semiconductor device source, channel and drain regions; and separate means for biasing each backgate electrode independently.

References Cited (Backward Citations)

US4272880A Cited
JPS5688354A Cited
JPS5737661A Cited
JPS58175853A Cited
US4570175A Cited
JPS59182571A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-05-31 1991-11-30 1992-05-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-05-31 1995-11-30 1996-05-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-05-31 1999-11-30 2000-05-31 $7700.00 Window Closed / Lapsed

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