US5596208A
Expired / Lapsed
US
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Article comprising an organic thin film transistor
Assignee: Nokia of America Corp
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Filing: 1996-05-10
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Granted: 1997-01-21
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Expires: 2016-05-10
Abstract
Abstract Articles according to the invention comprise an improved organic thin film transistor (TFT) that can have substantially higher source/drain current on/off ratio than conventional organic TFTs. An exemplary TFT according to the invention comprises, in addition to a p-type first organic material layer (e.g., α-6T), an n-type second organic material layer (e.g., Alq) in contact with the first material layer. TFTs according to the invention can be advantageously used in, for instance, active liquid crystal displays and electronic memories.
Inventors
- 👤 Ananth Dodabalapur
- 👤 Howard E. Katz
- 👤 Luisa Torsi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:52
CPC Classifications
B; B82; B82Y; B82Y10/00; G; G11; G11C; G11C13/00; G11C13/0002; G11C13/0009; G11C13/0014; H; H10; H10K; H10K10/00; H10K10/40; H10K10/46; H10K10/462; H10K10/484; H10K10/486; G09; G09G; G09G2300/00; G09G2300/08; G09G3/00; G09G3/20; G09G3/34; G09G3/36; G09G3/3611; G09G3/3648; H10K10/464; H10K10/466; H10K19/00; H10K19/10; H10K85/00; H10K85/10; H10K85/111; H10K85/113; H10K85/20; H10K85/211; H10K85/30; H10K85/321; H10K85/324; H10K85/60; H10K85/649; H10K85/655
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
214 words
An article comprising a thin film transistor comprising a) a layer of organic material; b) spaced apart first and second contact means in contact with said layer of organic material; c) third contact means that are spaced from each of said first and second contact means and that are adapted for controlling, by means of a voltage applied to the third contact means, a current between the first and the second contact means; CHARACTERIZED IN THAT d) the layer of organic material comprises a layer of first organic material of a first conductivity type and a layer of a second organic material of a second conductivity type that is in contact with said layer of the first organic material at least in a region between said first and second contact means and forms a p-n junction therewith, the layer of the first organic material being in contact with each of the first and second contact means and being not in contact with the third contact means, wherein said first and second organic materials respectively have a first and a second energy gap between a highest occupied orbital and a lowest unoccupied orbital, and wherein said first and second organic materials are selected such that said first energy gap differs from said second energy gap.
Claim 2
Dependent Claim
214 words
An article comprising a thin film transistor comprising a) a layer of organic material; b) spaced apart first and second contact means in contact with said layer of organic material; c) third contact means that are spaced from each of said first and second contact means and that are adapted for controlling, by means of a voltage applied to the third contact means, a current between the first and the second contact means; CHARACTERIZED IN THAT d) the layer of organic material comprises a layer of first organic material of a first conductivity type and a layer of a second organic material of a second conductivity type that is in contact with said layer of the first organic material at least in a region between said first and second contact means and forms a p-n junction therewith, the layer of the first organic material being in contact with each of the first and second contact means and being not in contact with the third contact means, wherein said first and second organic materials respectively have a first and a second energy gap between a highest occupied orbital and a lowest unoccupied orbital, and wherein said first and second organic materials are selected such that said first energy gap differs from said second energy gap.
Claim 3
Dependent Claim
39 words
Article according to claim 1, wherein the transistor comprises a dielectric layer disposed between the third contact means and both of the first and second contact means, with the first organic material layer in contact with the dielectric layer.
Claim 4
Dependent Claim
16 words
Article according to claim 2, wherein the first organic material layer is an n-type material layer.
Claim 5
Dependent Claim
31 words
Article according to claim 1, wherein the third contact means are disposed on the layer of the second organic material and are spaced from the layer of the first organic material.
Claim 6
Dependent Claim
40 words
An article according to claim 1, wherein the thin film transistor exhibits an on/off ratio greater than 10 5 at an operating gate voltage and a carrier mobility of at least 5×10 -3 cm 2 /V·s, all at 20° C.
Claim 7
Dependent Claim
45 words
An article according to claim 5, wherein the first organic material is p-type semiconductor material, with the charge carrier mobility in the p-type material exceeding the charge carrier mobility in the n-type second organic material at least by a factor of 100 at 20° C.
Claim 8
Dependent Claim
40 words
An article according to claim 2, wherein associated with each of said first and second organic materials is a charge carrier mobility, with the respective first to second charge carrier mobility ratio being in the range 0.1-10 at 20° C.
Claim 9
Dependent Claim
19 words
An article according to claim 1, wherein at least the first organic material layer comprises polycrystalline first organic material.
Claim 10
Dependent Claim
20 words
An article according to claim 6, wherein the second organic material comprises material selected from Alq and C 60 .
Claim 11
Dependent Claim
40 words
An article according to claim 6, wherein the first organic material is selected from the group consisting of polymers of thiophene of degree of polymerization greater than three and less than nine, polymers of substituted derivatives of thiophene, and poly(thienylenevinylene).
Claim 12
Dependent Claim
25 words
An article according to claim 9, wherein the first organic material comprises material selected from the group consisting of α-6T, and substituted derivatives of α-6T.
Claim 13
Dependent Claim
46 words
An article according to claim 1, wherein the first and second semiconductor materials are selected such that (|E F1 -E F2 |/q)>0.5 V, where E F1 and E F2 are the first and second material Fermi energy, respectively, and q is the absolute elementary charge value.
Claim 14
Dependent Claim
16 words
An article according to claim 1, wherein the article comprises a multiplicity of thin film transistors.
Claim 15
Dependent Claim
18 words
An article according to claim 1, wherein the first organic material layer is an n-type organic material layer.
Claim 16
Dependent Claim
25 words
An article according to claim 8, wherein the polycrystalline first organic material has an average grain size, said average size being at least 2 μm.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2000-01-21 | 2000-07-22 | 2001-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-21 | 2004-07-22 | 2005-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-21 | 2008-07-22 | 2009-01-21 | $7700.00 | Window Closed / Lapsed |