US5616935A
Expired / Lapsed
US
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Semiconductor integrated circuit having N-channel and P-channel transistors
Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1995-02-01
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Granted: 1997-04-01
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Expires: 2015-02-01
Abstract
Abstract The absolute value of the threshold voltage of a P-channel TFT is reduced by making its channel length shorter than that of an N-channel TFT by at least 20%, to thereby approximately equalize the threshold voltage absolute values of those TFTs.
Inventors
- 👤 Jun Koyama
- 👤 Yasuhiko Takemura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:43
CPC Classifications
H; H10; H10D; H10D86/00; H10D86/40; H10D30/00; H10D30/60; H10D30/67; H10D30/6729; H10D30/673; H10D30/6737; H10D30/6739; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0165; H10D84/02; H10D84/03; H10D84/038; H10D84/80; H10D84/82; H10D84/83; H10D84/85; H10D84/856; H10D86/421; H10D86/441; H10D86/60
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
88 words
A semiconductor integrated circuit having N-channel and P-channel thin-film transistors formed on an insulating surface, each channel region of said N-channel and P-channel thin-film transistors comprising a crystalline silicon layer having a <111 > crystal orientation, wherein a channel length of the P-channel thin-film transistor is shorter than that of the N-channel thin film transistor by at least 20% and an absolute value of a threshold voltage of said P-channel thin-film transistor is approximately equal to an absolute value of a threshold voltage of said N-channel thin-film transistor.
Claim 2
Dependent Claim
88 words
A semiconductor integrated circuit having N-channel and P-channel thin-film transistors formed on an insulating surface, each channel region of said N-channel and P-channel thin-film transistors comprising a crystalline silicon layer having a <111 > crystal orientation, wherein a channel length of the P-channel thin-film transistor is shorter than that of the N-channel thin film transistor by at least 20% and an absolute value of a threshold voltage of said P-channel thin-film transistor is approximately equal to an absolute value of a threshold voltage of said N-channel thin-film transistor.
Claim 3
Dependent Claim
105 words
A semiconductor integrated circuit having N-channel and P-channel thin-film transistors formed on an insulating surface, each channel region of said N-channel and P-channel thin-film transistors comprising a crystalline silicon layer having a <111> crystal orientation, wherein gate electrodes of the N-channel thin-film transistor and the P-channel thin-film transistor are connected to each other, and wherein a channel length of the P-channel thin-film transistor is shorter than that of the N-channel thin-film transistor by at least 20% and an absolute value of a threshold voltage of said P-channel thin-film transistor is approximately equal to an absolute value of a threshold voltage of said N-channel thin-film transistor.
Claim 4
Dependent Claim
105 words
A semiconductor integrated circuit having N-channel and P-channel thin-film transistors formed on an insulating surface, each channel region of said N-channel and P-channel thin-film transistors comprising a crystalline silicon layer having a <111> crystal orientation, wherein gate electrodes of the N-channel thin-film transistor and the P-channel thin-film transistor are connected to each other, and wherein a channel length of the P-channel thin-film transistor is shorter than that of the N-channel thin-film transistor by at least 20% and an absolute value of a threshold voltage of said P-channel thin-film transistor is approximately equal to an absolute value of a threshold voltage of said N-channel thin-film transistor.
Claim 5
Dependent Claim
53 words
A semiconductor integrated circuit comprising thin-film transistors each having a gate electrode that is mainly made of aluminum, wherein a channel length of a P-channel thin-film transistor is made shorter than that of an N-channel thin-film transistor to approximately equalize an absolute value of threshold voltages of the P-channel and N-channel thin-film transistors.
Claim 6
Dependent Claim
53 words
A semiconductor integrated circuit comprising thin-film transistors each having a gate electrode that is mainly made of aluminum, wherein a channel length of a P-channel thin-film transistor is made shorter than that of an N-channel thin-film transistor to approximately equalize an absolute value of threshold voltages of the P-channel and N-channel thin-film transistors.
Claim 7
Dependent Claim
78 words
A semiconductor integrated circuit having at least one complementary P-channel and N-channel transistors formed on an insulating surface, said P-channel and N-channel transistors having respective gate electrodes comprising aluminum, wherein a channel length of the P-channel thin-film transistor is shorter than that of the N-channel thin-film transistor by at least 20% and an absolute value of a threshold voltage of said P-channel transistor is approximately equal to an absolute value of a threshold voltage of said N-channel transistor.
Claim 8
Dependent Claim
78 words
A semiconductor integrated circuit having at least one complementary P-channel and N-channel transistors formed on an insulating surface, said P-channel and N-channel transistors having respective gate electrodes comprising aluminum, wherein a channel length of the P-channel thin-film transistor is shorter than that of the N-channel thin-film transistor by at least 20% and an absolute value of a threshold voltage of said P-channel transistor is approximately equal to an absolute value of a threshold voltage of said N-channel transistor.
Claim 9
Dependent Claim
93 words
A semiconductor integrated circuit comprising p-channel and n-channel thin film transistors each having a gate electrode comprising aluminum, wherein the width of the gate electrode of said p-channel transistor in a direction along source and drain regions is shorter than that of said n-channel transistor by at least 25% and wherein a channel region of said thin film transistors comprises crystalline silicon having <111> crystal orientation and an absolute value of a threshold voltage of said P-channel transistor is approximately equal to an absolute value of a threshold voltage of said N-channel transistor.
Claim 10
Dependent Claim
93 words
A semiconductor integrated circuit comprising p-channel and n-channel thin film transistors each having a gate electrode comprising aluminum, wherein the width of the gate electrode of said p-channel transistor in a direction along source and drain regions is shorter than that of said n-channel transistor by at least 25% and wherein a channel region of said thin film transistors comprises crystalline silicon having <111> crystal orientation and an absolute value of a threshold voltage of said P-channel transistor is approximately equal to an absolute value of a threshold voltage of said N-channel transistor.
Claim 11
Dependent Claim
28 words
The semiconductor integrated circuit of claim 5 wherein the width of the gate electrode of said p-channel transistor is shorter than that of said n-channel transistor by 25-80%.
Claim 12
Dependent Claim
29 words
The semiconductor integrated circuit of claim 5 wherein a channel region of each of said p-channel and n-channel thin film transistors comprises a non-single crystalline silicon having a crystallinity.
Claim 13
Dependent Claim
14 words
The semiconductor integrate circuit of claim 7 wherein said non-single crystalline silicon is polysilicon.
Claim 14
Dependent Claim
31 words
The semiconductor integrated circuit of claim 5 wherein said p-channel transistor and n-channel transistor each contains N-type or P-type impurity at a concentration not higher than 1×10 18 atoms/cm 3 .
Claim 15
Dependent Claim
25 words
The semiconductor integrated circuit of claim 1, 2, or 5 wherein the crystal silicon layer of said N-channel and P-channel transistors is 300-5000 Å thick.
Claim 16
Dependent Claim
39 words
The semiconductor integrated circuit of claim 1, 2, or 5 wherein the crystal silicon layer of said N-channel and P-channel transistors contains an N-type or P-type impurity at a concentration of not higher than 1×10 18 atoms/cm 3 .
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 2000-03-31 | 2000-09-30 | 2001-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-03-31 | 2004-09-30 | 2005-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-03-31 | 2008-09-30 | 2009-04-01 | $7700.00 | Window Closed / Lapsed |