US5744822A
Expired / Lapsed
US
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Semiconductor device/circuit having at least partially crystallized semiconductor layer
Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1997-01-24
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Granted: 1998-04-28
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Expires: 2017-01-24
Abstract
Abstract Amorphous silicon in impurity regions (source and drain regions or N-type or p-type regions) of TFT and TFD are crystallized and activated to lower electric resistance, by depositing film having a catalyst element such as nickel (Ni), iron (Fe), cobalt (Co) or platinum (Pt) on or beneath an amorphous silicon film, or introducing such a catalyst element into the amorphous silicon film by ion implantation and subsequently crystallizing the same by applying heat annealing at an appropriate temperature.
Inventors
- 👤 Toru Takayama
- 👤 Yasuhiko Takemura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:06
CPC Classifications
H; H10; H10D; H10D8/00; H10D8/01; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0321; H10D86/00; H10D86/01; H10D86/40; H10D86/60
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
98 words
A p-channel type thin film transistor comprising: source and drain semiconductor regions having a p-type conductivity, said source and drain semiconductor regions doped with a p-type impurity and formed in a crystalline semiconductor film comprising silicon; and a channel semiconductor region formed in said crystalline semiconductor film and extending between said source and drain regions, wherein at least said source and drain semiconductor regions of the semiconductor film contain a catalyst metal which is capable of promoting crystallization of said semiconductor film and said source and drain regions of the crystalline semiconductor film are selectively doped with phosphorus.
Claim 2
Dependent Claim
98 words
A p-channel type thin film transistor comprising: source and drain semiconductor regions having a p-type conductivity, said source and drain semiconductor regions doped with a p-type impurity and formed in a crystalline semiconductor film comprising silicon; and a channel semiconductor region formed in said crystalline semiconductor film and extending between said source and drain regions, wherein at least said source and drain semiconductor regions of the semiconductor film contain a catalyst metal which is capable of promoting crystallization of said semiconductor film and said source and drain regions of the crystalline semiconductor film are selectively doped with phosphorus.
Claim 3
Dependent Claim
13 words
The thin film transistor of claim 1 wherein said p-type impurity is boron.
Claim 4
Dependent Claim
35 words
The thin film transistor of claim 2 wherein a concentration of said phosphorous in said source and drain semiconductor regions is smaller than a concentration of said boron in said source and drain semiconductor regions.
Claim 5
Dependent Claim
16 words
The thin film transistor of claim 1 wherein said channel semiconductor region contains said catalyst metal.
Claim 6
Dependent Claim
32 words
The thin film transistor of claim 1 wherein said catalyst metal is contained in said source and drain semiconductor regions at a concentration from 1×10 17 to 2×10 20 atoms/cm 3 .
Claim 7
Dependent Claim
23 words
The thin film transistor of claim 1 wherein said catalyst metal is selected from the group consisting of nickel, iron, cobalt and platinum.
Claim 8
Dependent Claim
106 words
A complementary semiconductor device comprising: a substrate; a p-channel thin film transistor formed over said substrate and having at least source and drain regions comprising a p-type crystalline semiconductor material doped with a p-type impurity and a channel semiconductor layer extending therebetween; and an n-channel thin film transistor formed over said substrate and having at least source and drain regions comprising an-type crystalline semiconductor material doped with phosphorus and a channel semiconductor layer extending therebetween, wherein the source and drain regions of said p-channel transistor are selectively doped with both of phosphorus and a catalyst metal capable of promoting a crystallization of p-type crystalline semiconductor material.
Claim 9
Dependent Claim
106 words
A complementary semiconductor device comprising: a substrate; a p-channel thin film transistor formed over said substrate and having at least source and drain regions comprising a p-type crystalline semiconductor material doped with a p-type impurity and a channel semiconductor layer extending therebetween; and an n-channel thin film transistor formed over said substrate and having at least source and drain regions comprising an-type crystalline semiconductor material doped with phosphorus and a channel semiconductor layer extending therebetween, wherein the source and drain regions of said p-channel transistor are selectively doped with both of phosphorus and a catalyst metal capable of promoting a crystallization of p-type crystalline semiconductor material.
Claim 10
Dependent Claim
97 words
A semiconductor device having at least one p-channel thin film transistor, said thin film transistor comprising: source and drain crystalline semiconductor regions having a p-type conductivity and comprising silicon; a channel semiconductor region extending between said source and drain regions; a gate electrode adjacent said channel region and insulated therefrom; an anodic oxide layer formed on said gate electrode, said anodic oxide layer comprising an oxide of a material of said gate electrode, wherein said source and drain regions are selectively doped with a p-type impurity, phosphorus and a catalyst metal capable of promoting crystallization of silicon.
Claim 11
Dependent Claim
97 words
A semiconductor device having at least one p-channel thin film transistor, said thin film transistor comprising: source and drain crystalline semiconductor regions having a p-type conductivity and comprising silicon; a channel semiconductor region extending between said source and drain regions; a gate electrode adjacent said channel region and insulated therefrom; an anodic oxide layer formed on said gate electrode, said anodic oxide layer comprising an oxide of a material of said gate electrode, wherein said source and drain regions are selectively doped with a p-type impurity, phosphorus and a catalyst metal capable of promoting crystallization of silicon.
Claim 12
Dependent Claim
91 words
A semiconductor device having at least one p-channel thin film transistor, said thin film transistor comprising: a semiconductor layer comprising silicon and including source and drain regions and a channel region extending therebetween; and a gate electrode adjacent and insulated from said channel region, wherein said channel region extends beyond side edges of said gate electrode in a direction along said source and drain regions, and wherein said source and drain regions are doped with a p-type impurity, an n-type impurity and a catalyst metal capable of promoting crystallization of silicon.
Claim 13
Dependent Claim
91 words
A semiconductor device having at least one p-channel thin film transistor, said thin film transistor comprising: a semiconductor layer comprising silicon and including source and drain regions and a channel region extending therebetween; and a gate electrode adjacent and insulated from said channel region, wherein said channel region extends beyond side edges of said gate electrode in a direction along said source and drain regions, and wherein said source and drain regions are doped with a p-type impurity, an n-type impurity and a catalyst metal capable of promoting crystallization of silicon.
Claim 14
Dependent Claim
27 words
A complementary semiconductor device according to claim 7 wherein said p-type crystalline semiconductor material and the channel semiconductor layer of the p-channel thin film transistor comprise silicon.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2001-04-27 | 2001-10-27 | 2002-04-28 | $2000.00 | Window Closed / Lapsed |
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