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US5535155A Expired / Lapsed US ⏱️ 0.0 years remaining

SRAM cell having load thin film transistors

Assignee: PS4 Luxco SARL
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Filing: 1995-07-05
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Granted: 1996-07-09
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Expires: 2015-07-05
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Abstract

Abstract In a static random access memory device including a flip-flop having first and second load thin film transistors whose drains are connected via first and second transfer bulk transistors to first and second bit lines, respectively, the second bit line is arranged over the first load thin film transistor, and the first bit line is arranged over the second load thin film transistor.

Inventors

  • 👤 Kazuhiko Abe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 18:45
CPC Classifications
H; H10; H10B; H10B10/00; H10B10/12; H10B10/125; G; G11; G11C; G11C11/00; G11C11/21; G11C11/34; G11C11/40; G11C11/41; G11C11/412; H10D; H10D84/00; Y; Y10; Y10S; Y10S257/00; Y10S257/903

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 232 words
A static random access memory device comprising: first and second power supply lines; a word line; first and second bit lines; first and second nodes; a first load thin film transistor connected between said first power supply line and said first node and having a gate electrode connected to said second node; a second load thin film transistor connected between said first power supply line and said second node and having a gate electrode connected to said first node; a first drive bulk transistor connected between said first node and said second power supply line and having a gate electrode connected to said second node; a second drive bulk transistor connected between said second node and said second power supply line and having a gate electrode connected to said first node; a first transfer bulk transistor connected between said first bit line and said first node and having a gate electrode connected to said word line; and a second transfer bulk transistor connected between said second bit line and said second node and having a gate electrode connected to said word line, said second bit line being arranged in the proximity of said first load thin film transistor to create a first parasitic load thin film transistor, said first bit line being arranged in the proximity of said second load thin film transistor to create a second parasitic load thin film transistor.
Claim 2
Dependent Claim 232 words
A static random access memory device comprising: first and second power supply lines; a word line; first and second bit lines; first and second nodes; a first load thin film transistor connected between said first power supply line and said first node and having a gate electrode connected to said second node; a second load thin film transistor connected between said first power supply line and said second node and having a gate electrode connected to said first node; a first drive bulk transistor connected between said first node and said second power supply line and having a gate electrode connected to said second node; a second drive bulk transistor connected between said second node and said second power supply line and having a gate electrode connected to said first node; a first transfer bulk transistor connected between said first bit line and said first node and having a gate electrode connected to said word line; and a second transfer bulk transistor connected between said second bit line and said second node and having a gate electrode connected to said word line, said second bit line being arranged in the proximity of said first load thin film transistor to create a first parasitic load thin film transistor, said first bit line being arranged in the proximity of said second load thin film transistor to create a second parasitic load thin film transistor.
Claim 3
Dependent Claim 65 words
A device as set forth in claim 1, wherein said second bit line is located in an opposite side of said gate electrode of said first load thin film transistor in respect to a source-channel-drain layer thereof, said first bit line being located in an opposite side of said gate electrode of said second load thin film transistor in respect to a source-channel-drain layer thereof.
Claim 4
Dependent Claim 243 words
A static random access memory device comprising: first and second power supply lines; first and second word lines to which the same potential is applied; first and second bit lines; first and second nodes; a first load thin film transistor connected between said first power supply line and said first node and having a gate electrode connected to said second node; a second load thin film transistor connected between said first power supply line and said second node and having a gate electrode connected to said first node; a first drive bulk transistor connected between said first node and said second power supply line and having a gate electrode connected to said second node; a second drive bulk transistor connected between said second node and said second power supply line and having a gate electrode connected to said first node; a first transfer bulk transistor connected between said first bit line and said first node and having a gate electrode connected to said first word line; and a second transfer bulk transistor connected between said second bit line and said second node and having a gate electrode connected to said second word line, said second bit line being arranged in the proximity of said first load thin film transistor to create a first parasitic load thin film transistor, said first bit line being arranged in the proximity of said second load thin film transistor to create a second parasitic load thin film transistor.
Claim 5
Dependent Claim 243 words
A static random access memory device comprising: first and second power supply lines; first and second word lines to which the same potential is applied; first and second bit lines; first and second nodes; a first load thin film transistor connected between said first power supply line and said first node and having a gate electrode connected to said second node; a second load thin film transistor connected between said first power supply line and said second node and having a gate electrode connected to said first node; a first drive bulk transistor connected between said first node and said second power supply line and having a gate electrode connected to said second node; a second drive bulk transistor connected between said second node and said second power supply line and having a gate electrode connected to said first node; a first transfer bulk transistor connected between said first bit line and said first node and having a gate electrode connected to said first word line; and a second transfer bulk transistor connected between said second bit line and said second node and having a gate electrode connected to said second word line, said second bit line being arranged in the proximity of said first load thin film transistor to create a first parasitic load thin film transistor, said first bit line being arranged in the proximity of said second load thin film transistor to create a second parasitic load thin film transistor.
Claim 6
Dependent Claim 65 words
A device as set forth in claim 3, wherein said second bit line is located in an opposite side of said gate electrode of said first load thin film transistor in respect to a source-channel-drain layer thereof, said first bit line being located in an opposite side of said gate electrode of said second load thin film transistor in respect to a source-channel-drain layer thereof.
Claim 7
Dependent Claim 51 words
A device as set forth in claim 3, wherein said first and second word lines, said first and second bit lines, said first and second thin film transistors, said first and second drive bulk transistors, and said first second transfer bulk transistors are symmetrical with respect to one center of symmetry.
Claim 8
Dependent Claim 62 words
A static random access memory device including a flip-flop having first and second load thin film transistors whose drains are connected via first and second transfer bulk transistors to first and second bit lines, respectively, wherein said second bit line is arranged over said first load thin film transistor, and said first bit line is arranged over said second thin film transistor.
Claim 9
Dependent Claim 62 words
A static random access memory device including a flip-flop having first and second load thin film transistors whose drains are connected via first and second transfer bulk transistors to first and second bit lines, respectively, wherein said second bit line is arranged over said first load thin film transistor, and said first bit line is arranged over said second thin film transistor.
Claim 10
Dependent Claim 120 words
A static random access memory device including a flip-flop having first and second load thin film transistors whose drains are connected via first and second transfer bulk transistors to first and second bit lines, respectively, wherein a gate electrode of said first load thin film transistor is located beneath a channel region of said first load thin film transistor, and said second bit line is located over said channel region of said first load thin film transistor, and wherein a gate electrode of said second load thin film transistor is located beneath a channel region of said second load thin film transistor, and said first bit line is located over said channel region of said second load thin film transistor.
Claim 11
Dependent Claim 120 words
A static random access memory device including a flip-flop having first and second load thin film transistors whose drains are connected via first and second transfer bulk transistors to first and second bit lines, respectively, wherein a gate electrode of said first load thin film transistor is located beneath a channel region of said first load thin film transistor, and said second bit line is located over said channel region of said first load thin film transistor, and wherein a gate electrode of said second load thin film transistor is located beneath a channel region of said second load thin film transistor, and said first bit line is located over said channel region of said second load thin film transistor.

References Cited (Backward Citations)

EP0426174A2 Cited
US5281843A Cited
US5309010A Cited
US5438537A Cited
US5404326A Cited
US5384731A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-07-09 2000-01-08 2000-07-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-07-09 2004-01-08 2004-07-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-07-09 2008-01-08 2008-07-09 $7700.00 Window Closed / Lapsed

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