US4978631A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current source with a process selectable temperature coefficient
Assignee: Vishay Siliconix Inc
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Filing: 1986-07-25
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Granted: 1990-12-18
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Expires: 2006-07-25
Abstract
Abstract A transistor (Q3, Q4) is configured to act as a current source. Of importance, the current provided by the current source has a process-selectable temperature dependence. By introducing ions into the transistor gate insulation (14, 20) the current provided by the current source can be either temperature independent, inversely related to temperature, or directly related to temperature, as desired.
Inventors
- 👤 Richard A. Blanchard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:29
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/64; H10D30/66; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/0134; H10D64/60; H10D64/66; H10D64/68
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
101 words
A method for forming a current source comprising the steps of: forming a gate insulation layer on a portion of a surface of semiconductor material; introducing ions into said gate insulation layer, said ions retaining their charge; forming a gate on said gate insulation layer; forming a source region and a drain region within said semiconductor material; and electrically connecting said source region to said gate, wherein said method further comprises the step of controlling the temperature coefficient of said current source, said step of controlling comprising the step of controlling the number of said ions in said gate insulation layer.
Claim 2
Independent Claim
101 words
A method for forming a current source comprising the steps of: forming a gate insulation layer on a portion of a surface of semiconductor material; introducing ions into said gate insulation layer, said ions retaining their charge; forming a gate on said gate insulation layer; forming a source region and a drain region within said semiconductor material; and electrically connecting said source region to said gate, wherein said method further comprises the step of controlling the temperature coefficient of said current source, said step of controlling comprising the step of controlling the number of said ions in said gate insulation layer.
Claim 3
Independent Claim
109 words
A method for forming a current source comprising the steps of: forming a gate insulation layer on a portion of a surface of semiconductor material; introducing ions into said gate insulation layer, said ions retaining their charge; forming a gate on said gate insulation layer; forming a source and a body region within said semiconductor material, a portion of said semiconductor material serving as a drain; and electrically connecting said source region to said gate, wherein said method further comprises the step of controlling the temperature coefficient of said current source, said step of controlling comprising the step of controlling the number of ions in said gate insulation layer.
Claim 4
Independent Claim
109 words
A method for forming a current source comprising the steps of: forming a gate insulation layer on a portion of a surface of semiconductor material; introducing ions into said gate insulation layer, said ions retaining their charge; forming a gate on said gate insulation layer; forming a source and a body region within said semiconductor material, a portion of said semiconductor material serving as a drain; and electrically connecting said source region to said gate, wherein said method further comprises the step of controlling the temperature coefficient of said current source, said step of controlling comprising the step of controlling the number of ions in said gate insulation layer.
Claim 5
Dependent Claim
20 words
The method of claim 1 or 2 wherein the current provided by said current source is inversely related to temperature.
Claim 6
Dependent Claim
17 words
The method of claim 1 or 2 wherein the current provided by said current source is temperature-independent.
Claim 7
Dependent Claim
23 words
The method of claim 1 or 2 wherein the current provided by said current source increases in response to an increase in temperature.
Claim 8
Dependent Claim
12 words
The method of claim 1 or 2 wherein said ions are positive.
Claim 9
Dependent Claim
12 words
The method of claim 1 or 2 wherein said ions are negative.
Claim 10
Dependent Claim
14 words
The method of claim 1 or 2 wherein said ions comprise cesium or iodine.
Claim 11
Independent Claim
100 words
A method for forming a current source comprising the steps of: forming a gate insulation layer on a portion of a surface of semiconductor material; introducing ions into said gate insulation layer, said ions retaining their charge; forming a source and drains within said semiconductor material; forming a gate on said gate insulation layer; and providing a DC voltage across said gate and source, and wherein said method further comprises the step of controlling the temperature coefficient of said current source, said step of controlling comprising said step of controlling the number of said ions in said gate insulation layer.
Claim 12
Independent Claim
100 words
A method for forming a current source comprising the steps of: forming a gate insulation layer on a portion of a surface of semiconductor material; introducing ions into said gate insulation layer, said ions retaining their charge; forming a source and drains within said semiconductor material; forming a gate on said gate insulation layer; and providing a DC voltage across said gate and source, and wherein said method further comprises the step of controlling the temperature coefficient of said current source, said step of controlling comprising said step of controlling the number of said ions in said gate insulation layer.
Claim 13
Independent Claim
110 words
A method for forming a current source comprising the steps of: forming a gate insulation layer on a portion of a surface of semiconductor material; introducing ions into said gate insulation layer, said ions retaining their charge; forming a gate on said gate insulation layer; forming a source and body region within said semiconductor material, a portion of said semiconductor material serving as a drain; and providing a DC voltage across said gate and source, and wherein said method further comprises the step of controlling the temperature coefficient of said current source, said step of controlling comprising the step of controlling the number of ions in said gate insulation layer.
Claim 14
Independent Claim
110 words
A method for forming a current source comprising the steps of: forming a gate insulation layer on a portion of a surface of semiconductor material; introducing ions into said gate insulation layer, said ions retaining their charge; forming a gate on said gate insulation layer; forming a source and body region within said semiconductor material, a portion of said semiconductor material serving as a drain; and providing a DC voltage across said gate and source, and wherein said method further comprises the step of controlling the temperature coefficient of said current source, said step of controlling comprising the step of controlling the number of ions in said gate insulation layer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-17 | 1994-06-18 | 1994-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-17 | 1998-06-18 | 1998-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-17 | 2002-06-18 | 2002-12-18 | $7700.00 | Window Closed / Lapsed |