US5317181A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alternative body contact for fully-depleted silicon-on-insulator transistors
Assignee: Frontgrade Colorado Springs LLC
•
Filing: 1992-09-10
•
Granted: 1994-05-31
•
Expires: 2012-09-10
Abstract
Abstract Two preferred embodiments for an alternative body contact are disclosed for fully-depleted silicon-on-insulator transistors. In one preferred embodiment, body contact is made by extending the mesa ends of the body ties down to, and merging them with, mesa regions of an nFET source and using self-aligned silicide (commonly known as salicide) to make a connection to an underlying nFET well. In this first embodiment, the mesas of the body ties merge with the mesa of the source and salicide is used to short out these regions. In another preferred embodiment, body contact is made by extending the mesa ends of the body ties down to the nFET source; however, the mesas are not merged. In this second embodiment, metal routing, which is commonly used to electrically connect circuit elements, is extended to connect to the mesa regions of the body ties. In both embodiments, the body ties are active until the onset of full depletion; however, at the onset of full depletion, the body ties are electrically severed.
Inventors
- 👤 Scott M. Tyson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:35
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/711; H10D30/67; H10D30/6704; H10D30/6708
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
176 words
A transistor formed on an island of silicon over an insulator film over a silicon substrate comprising: a. a channel region in the silicon island; b. a source region comprising a mesa formed in the silicon island; c. a drain region formed in the silicon island and being spaced from the source region and defining the channel region therebetween; d. a gate extending over the channel region for controlling surface potential in the channel region; e. an insulator region lying between the gate and the channel and separating the gate from the channel region; f. at least one body tie region disposed adjacent to and in abutting relation with the channel region and disposed along a predetermined length of the source and being separated from the source by an aperture; and g. a layer of metal routing overlying the body tie region and the mesa of the source region for electrically connecting the two regions, wherein electrical connection between the channel region and the body tie region is severed when the channel region achieves full depletion.
Claim 2
Dependent Claim
176 words
A transistor formed on an island of silicon over an insulator film over a silicon substrate comprising: a. a channel region in the silicon island; b. a source region comprising a mesa formed in the silicon island; c. a drain region formed in the silicon island and being spaced from the source region and defining the channel region therebetween; d. a gate extending over the channel region for controlling surface potential in the channel region; e. an insulator region lying between the gate and the channel and separating the gate from the channel region; f. at least one body tie region disposed adjacent to and in abutting relation with the channel region and disposed along a predetermined length of the source and being separated from the source by an aperture; and g. a layer of metal routing overlying the body tie region and the mesa of the source region for electrically connecting the two regions, wherein electrical connection between the channel region and the body tie region is severed when the channel region achieves full depletion.
Claim 3
Dependent Claim
17 words
The transistor of claim 1, wherein the transistor is sufficiently doped to create a P channel device.
Claim 4
Dependent Claim
17 words
The transistor of claim 1, wherein the transistor is sufficiently doped to create an N channel device.
Claim 5
Dependent Claim
26 words
The transistor of claim 1, wherein a plurality of body tie regions extend outwardly from the gate and extend to the mesa of the source region.
Claim 6
Dependent Claim
12 words
The transistor of claim 1, wherein the insulator film comprises silicon dioxide.
Claim 7
Dependent Claim
11 words
The transistor of claim 1, wherein the insulator film comprises sapphire.
Claim 8
Dependent Claim
11 words
The transistor of claim 1, wherein the insulator film comprises spinel.
Claim 9
Dependent Claim
164 words
A transistor formed on an island of silicon over an insulator film over a silicon substrate comprising: a. a channel region in the silicon island; b. a source region comprising a mesa formed in the silicon island; c. a drain region formed in the silicon island and being spaced from the source region and defining the channel region therebetween; d. a gate extending over the channel region for controlling surface potential in the channel region; e. an insulator region lying between the gate and the channel and separating the gate from the channel region; f. at least one body tie region disposed adjacent to and in abutting relation with the channel region and disposed along a predetermined length of the source and being separated from the source by an aperture; and g. a means for electrically connecting the source to the body tie, wherein electrical connection between the channel region and the body tie region is severed when the channel region achieves full depletion.
Claim 10
Dependent Claim
164 words
A transistor formed on an island of silicon over an insulator film over a silicon substrate comprising: a. a channel region in the silicon island; b. a source region comprising a mesa formed in the silicon island; c. a drain region formed in the silicon island and being spaced from the source region and defining the channel region therebetween; d. a gate extending over the channel region for controlling surface potential in the channel region; e. an insulator region lying between the gate and the channel and separating the gate from the channel region; f. at least one body tie region disposed adjacent to and in abutting relation with the channel region and disposed along a predetermined length of the source and being separated from the source by an aperture; and g. a means for electrically connecting the source to the body tie, wherein electrical connection between the channel region and the body tie region is severed when the channel region achieves full depletion.
Claim 11
Dependent Claim
40 words
The transistor device of claim 8, wherein the means for electrically connecting the two regions comprises a layer of metal routing overlying the body tie region and the mesa of the source region sufficiently so as to make electrical connection.
Claim 12
Dependent Claim
17 words
The transistor of claim 8, wherein the transistor is sufficiently doped to create an P channel device.
Claim 13
Dependent Claim
17 words
The transistor of claim 8, wherein the transistor is sufficiently doped to create an N channel device.
Claim 14
Dependent Claim
26 words
The transistor of claim 8, wherein a plurality of body tie regions extend outwardly from the gate and extend to the mesa of the source region.
Claim 15
Dependent Claim
12 words
The transistor of claim 8, wherein the insulator film comprises silicon dioxide.
Claim 16
Dependent Claim
11 words
The transistor of claim 8, wherein the insulator film comprises sapphire.
Claim 17
Dependent Claim
11 words
The transistor of claim 8, wherein the insulator film comprises spinel.
References Cited (Backward Citations)
US4946799A
Cited
US4906587A
Cited
US5079605A
Cited
US5001528A
Cited
US5095348A
Cited
US5145802A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-05-30 | 1997-11-29 | 1998-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-05-30 | 2001-11-29 | 2002-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-05-30 | 2005-11-29 | 2006-05-31 | $7700.00 | Window Closed / Lapsed |