Patent US5365080A successfully refreshed from Google Patents.
US5365080A
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US
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Field effect transistor with crystallized channel region
Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1994-02-14
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Granted: 1994-11-15
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Expires: 2014-02-14
Abstract
Abstract A semiconductor device which is excellent in reliability and electrical characteristics. The semiconductor device is formed on an insulating substrate. A channel region is formed between a source and a drain by the voltage applied to a gate electrode. The channel region, the source, and the drain are fabricated from a semiconductor having a large mobility. The other regions including the portion located under the channel region are fabricated from a semiconductor having a small mobility.
Inventors
- 👤 Shunpei Yamazaki
- 👤 Yasuhiko Takemura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:30
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0321; H10D30/60; H10D30/67; H10D30/6704; H10D30/6713; H10D30/6729; H10D30/673; H10D30/6731; H10D30/674; H10D30/6741; H10D30/6743; H10D30/6745
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
70 words
A semiconductor device comprising: a semiconductor layer; source and drain regions provided in said semiconductor layer; a channel region located between said source and drain regions in said semiconductor layer; and a gate electrode provided adjacent to said channel region with a gate insulator therebetween, wherein the crystallinity of an upper portion of said semiconductor layer is higher than a lower portion of said semiconductor layer below said upper portion.
Claim 2
Dependent Claim
70 words
A semiconductor device comprising: a semiconductor layer; source and drain regions provided in said semiconductor layer; a channel region located between said source and drain regions in said semiconductor layer; and a gate electrode provided adjacent to said channel region with a gate insulator therebetween, wherein the crystallinity of an upper portion of said semiconductor layer is higher than a lower portion of said semiconductor layer below said upper portion.
Claim 3
Dependent Claim
17 words
The device of claim 1 wherein said semiconductor layer is a semiconductor film provided on a substrate.
Claim 4
Dependent Claim
21 words
The device of claim 1 wherein said upper portion of the semiconductor layer has a larger mobility than said lower portion.
Claim 5
Dependent Claim
13 words
The device of claim 1 wherein said lower portion comprises an amorphous semiconductor.
Claim 6
Dependent Claim
15 words
The device of claim 1 wherein said source and drain regions comprise a polycrystal semiconductor.
Claim 7
Dependent Claim
14 words
The device of claim 1 wherein said device is provided on a integrated circuit.
Claim 8
Dependent Claim
14 words
The device of claim 1 wherein said upper portion comprises poly-crystalline or mono-crystalline semiconductor.
Claim 9
Dependent Claim
90 words
A semiconductor device comprising: a semiconductor layer formed on an insulating surface; a gate insulating layer formed on said semiconductor layer; a gate electrode formed on said gate insulating layer; source and drain regions formed within said semiconductor layer; and a channel region formed within said semiconductor layer under said gate insulating layer and between said source and drain regions, wherein an upper portion of said semiconductor layer beneath said gate insulating layer has a higher carrier mobility than a lower portion of said semiconductor layer below said upper portion.
Claim 10
Dependent Claim
90 words
A semiconductor device comprising: a semiconductor layer formed on an insulating surface; a gate insulating layer formed on said semiconductor layer; a gate electrode formed on said gate insulating layer; source and drain regions formed within said semiconductor layer; and a channel region formed within said semiconductor layer under said gate insulating layer and between said source and drain regions, wherein an upper portion of said semiconductor layer beneath said gate insulating layer has a higher carrier mobility than a lower portion of said semiconductor layer below said upper portion.
Claim 11
Dependent Claim
26 words
The semiconductor device of claim 8 wherein said upper portion of said semiconductor layer has a higher crystallinity than said lower portion of said semiconductor layer.
Claim 12
Dependent Claim
114 words
A semiconductor device comprising: a semiconductor substrate having at least one MOS transistor formed therein, including source, drain and channel regions and a gate electrode; an insulating layer covering said semiconductor substrate and said MOS transistor; and at least one thin film transistor formed on said insulating layer, said thin film transistor having source, drain and channel regions within one semiconductor layer, wherein the channel region of said thin film transistor is located over one of the source and drain regions of said at least one MOS transistor and one of the source and drain regions of said thin film transistor is located over the gate electrode of said at least one MOS transistor.
Claim 13
Dependent Claim
114 words
A semiconductor device comprising: a semiconductor substrate having at least one MOS transistor formed therein, including source, drain and channel regions and a gate electrode; an insulating layer covering said semiconductor substrate and said MOS transistor; and at least one thin film transistor formed on said insulating layer, said thin film transistor having source, drain and channel regions within one semiconductor layer, wherein the channel region of said thin film transistor is located over one of the source and drain regions of said at least one MOS transistor and one of the source and drain regions of said thin film transistor is located over the gate electrode of said at least one MOS transistor.
Claim 14
Dependent Claim
31 words
The semiconductor device of claim 10 wherein the channel region of said thin film transistor does not overlap with the gate electrode of said MOS transistor formed within said semiconductor substrate.
Claim 15
Dependent Claim
39 words
The device of claim 10 wherein an upper portion of said semiconductor layer is crystallized to form said channel region while the region of said semiconductor layer below said upper portion has a lower crystallinity than said upper portion.
Claim 16
Dependent Claim
101 words
A semiconductor device comprising: a semiconductor layer; source and drain regions provided in said semiconductor layer; a channel forming semiconductor region located between said source and drain regions in said semiconductor layer; a gate insulating layer adjacent to at least said channel forming semiconductor region; and a gate electrode adjacent to said gate insulating layer with said gate insulating layer interposed between said semiconductor layer and said gate electrode, where a portion of said channel forming region close to said gate insulating layer has a higher crystallinity than a portion of said channel semiconductor region distant from said gate insulating layer.
Claim 17
Dependent Claim
101 words
A semiconductor device comprising: a semiconductor layer; source and drain regions provided in said semiconductor layer; a channel forming semiconductor region located between said source and drain regions in said semiconductor layer; a gate insulating layer adjacent to at least said channel forming semiconductor region; and a gate electrode adjacent to said gate insulating layer with said gate insulating layer interposed between said semiconductor layer and said gate electrode, where a portion of said channel forming region close to said gate insulating layer has a higher crystallinity than a portion of said channel semiconductor region distant from said gate insulating layer.
Claim 18
Dependent Claim
29 words
The semiconductor of claim 13 wherein said device is formed on a semiconductor substrate with an insulating layer therebetween wherein a MOS transistor is formed within said semiconductor substrate.
Claim 19
Dependent Claim
25 words
The semiconductor device of claim 13 wherein said portion of the channel forming region close to said gate insulating layer comprises poly-crystalline or mono-crystalline semiconductor.
Claim 20
Dependent Claim
101 words
A semiconductor device comprising: a semiconductor layer; source and drain regions provided in said semiconductor layer; a channel forming semiconductor region located between said source and drain regions in said semiconductor layer; a gate insulating layer adjacent to at least said channel forming semiconductor region; and a gate electrode adjacent to said gate insulating layer with said gate insulating layer interposed between said semiconductor layer and said gale electrode, where a portion of said channel forming region close to said gate insulating layer has a higher mobility than a portion of said channel semiconductor region distant from said gate insulating layer.
Claim 21
Dependent Claim
101 words
A semiconductor device comprising: a semiconductor layer; source and drain regions provided in said semiconductor layer; a channel forming semiconductor region located between said source and drain regions in said semiconductor layer; a gate insulating layer adjacent to at least said channel forming semiconductor region; and a gate electrode adjacent to said gate insulating layer with said gate insulating layer interposed between said semiconductor layer and said gale electrode, where a portion of said channel forming region close to said gate insulating layer has a higher mobility than a portion of said channel semiconductor region distant from said gate insulating layer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-11-14 | 1998-05-16 | 1998-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-14 | 2002-05-16 | 2002-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-14 | 2006-05-16 | 2006-11-15 | $7700.00 | Window Closed / Lapsed |