Patent US5541436A successfully refreshed from Google Patents.
US5541436A
Expired / Lapsed
US
⏱️ 0.0 years remaining
MOS transistor having improved oxynitride dielectric
Assignee: The University of Texas System
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Filing: 1994-11-10
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Granted: 1996-07-30
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Expires: 2014-11-10
Abstract
Abstract High quality ultrathin gate oxides having nitrogen atoms therein with a profile having a peak at the silicon oxide-silicon interface are formed by oxidizing a surface of a monocrystalline silicon body in an atmosphere of nitrous oxide (N 2 O) at a temperature above 900° C. preferably in the range of 900°-1100° C., and then heating the silicon body and oxidized surface in an atmosphere of anhydrous ammonia to introduce additional nitrogen atoms into the oxide and increase resistance to boron penetration without degrading the oxide by charge trapping. The resulting oxynitride has less degradation under channel hot electron stress and approximately one order of magnitude longer lifetime than that of conventional silicon oxide in MIS applications.
Inventors
- 👤 Dim-Lee Kwong
- 👤 Giwan Yoon
- 👤 Jonghan Kim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:04
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/0134; H10D64/01344; H10D64/60; H10D64/66; H10D64/68; H10D64/693; Y; Y10; Y10S; Y10S148/00; Y10S148/112
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
110 words
A MIS transistor comprising a body of monocrystalline silicon having a major surface, a source region and a drain region formed in said body and abutting said major surface, said source region and said drain region being spaced apart with a channel region therebetween, an oxynitride layer on said major surface over said channel region, said oxynitride layer being heated in an atmosphere of anhydrous ammonia to introduce nitrogen atoms with said nitrogen atoms having a concentration profile with a peak at the oxynitride-silicon interface, and a gate electrode on said oxynitride layer over said channel region, said oxynitride layer extending continuously from said gate electrode to said channel region.
Claim 2
Dependent Claim
110 words
A MIS transistor comprising a body of monocrystalline silicon having a major surface, a source region and a drain region formed in said body and abutting said major surface, said source region and said drain region being spaced apart with a channel region therebetween, an oxynitride layer on said major surface over said channel region, said oxynitride layer being heated in an atmosphere of anhydrous ammonia to introduce nitrogen atoms with said nitrogen atoms having a concentration profile with a peak at the oxynitride-silicon interface, and a gate electrode on said oxynitride layer over said channel region, said oxynitride layer extending continuously from said gate electrode to said channel region.
Claim 3
Dependent Claim
25 words
The MIS transistor as defined by claim 1 wherein said oxynitride layer is formed by oxidizing said major surface in an atmosphere of nitrous oxide.
Claim 4
Dependent Claim
20 words
The MIS transistor as defined by claim 2 wherein said major surface is oxidized at a temperature above 1000° C.
Claim 5
Dependent Claim
19 words
The MIS transistor as defined by claim 2 wherein said major surface is oxidized at a temperature of 900°-1100°C.
Claim 6
Dependent Claim
27 words
This MIS transistor as defined by claim 1 wherein said nitrogen atoms are introduced in said atmosphere of anhydrous ammonia at a temperature of 800° C.-1100° C.
References Cited (Backward Citations)
US3422321A
Cited
US3629088A
Cited
US4188565A
Cited
US4621277A
Cited
JPS55113335A
Cited
US4581622A
Cited
US4438157A
Cited
WO1983002199A1
Cited
WO1984000852A1
Cited
JPS61172339A
Cited
US4702936A
Cited
US4620986A
Cited
US4623912A
Cited
US4721631A
Cited
WO1986005323A1
Cited
WO1987005439A1
Cited
US4901133A
Cited
EP0259826A1
Cited
EP0289246A1
Cited
EP0305741A2
Cited
JPS6469932A
Cited
US4981307A
Cited
JPH0218934A
Cited
WO1990003560A2
Cited
US5254506A
Cited
JPH03257828A
Cited
US5254489A
Cited
US5369297A
Cited
JPH05283679A
Cited
US5258333A
Cited
US5377139A
Cited
US5407870A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-07-30 | 2000-01-29 | 2000-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-07-30 | 2004-01-29 | 2004-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-07-30 | 2008-01-29 | 2008-07-30 | $7700.00 | Window Closed / Lapsed |