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US5596212A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor memory device and a manufacturing method of the same

Assignee: Renesas Electronics Corp
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Filing: 1995-07-21
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Granted: 1997-01-21
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Expires: 2015-07-21
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Abstract

Abstract A memory cell of an SRAM prevents imbalance between GND potentials of a pair of driver transistors. In the memory cell, the driver transistors Q 1 and Q 2 in a pair have the common source region.

Inventors

  • 👤 Hirotada Kuriyama

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 08:07
CPC Classifications
H; H10; H10B; H10B10/00; H10B10/12; H10B10/125; Y; Y10; Y10S; Y10S257/00; Y10S257/903; Y10S257/904

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 254 words
A semiconductor memory device including a memory cell provided with a pair of first and second driver transistors of a first conductivity type and a pair of first and second load transistors of a second conductivity type forming a flip-flop circuit, and a pair of first and second access transistors, said memory cell comprising: a gate electrode of said first driver transistor extending in a predetermined direction; a gate electrode of said second driver transistor, extending substantially in the same direction as said gate electrode of said first driver transistor with a predetermined space therebetween; and a word line extending substantially in the same direction as said gate electrode of said first driver transistor with a predetermined space therebetween, and forming gate electrodes of said first and second access transistors; wherein source regions of said first and second driver transistors are formed to be electrically connected together between said gate electrodes of said first and second driver transistors, wherein said first and second load transistors include first and second thin-film transistors formed on an interlayer insulating film located over the semiconductor substrate, said first and second access transistors are electrically connected to first and second bit lines extending above said first and second thin-film transistors, and said source regions of said first and second driver transistors are electrically connected to a ground interconnection layer having an upper portion extending at least in part directly under said first and second bit lines and at least in part directly above said first and second thin-film transistors.
Claim 2
Dependent Claim 254 words
A semiconductor memory device including a memory cell provided with a pair of first and second driver transistors of a first conductivity type and a pair of first and second load transistors of a second conductivity type forming a flip-flop circuit, and a pair of first and second access transistors, said memory cell comprising: a gate electrode of said first driver transistor extending in a predetermined direction; a gate electrode of said second driver transistor, extending substantially in the same direction as said gate electrode of said first driver transistor with a predetermined space therebetween; and a word line extending substantially in the same direction as said gate electrode of said first driver transistor with a predetermined space therebetween, and forming gate electrodes of said first and second access transistors; wherein source regions of said first and second driver transistors are formed to be electrically connected together between said gate electrodes of said first and second driver transistors, wherein said first and second load transistors include first and second thin-film transistors formed on an interlayer insulating film located over the semiconductor substrate, said first and second access transistors are electrically connected to first and second bit lines extending above said first and second thin-film transistors, and said source regions of said first and second driver transistors are electrically connected to a ground interconnection layer having an upper portion extending at least in part directly under said first and second bit lines and at least in part directly above said first and second thin-film transistors.
Claim 3
Dependent Claim 18 words
The semiconductor memory device according to claim 1, wherein said ground interconnection layer includes a metal interconnection layer.
Claim 4
Dependent Claim 177 words
A semiconductor memory device including a memory cell provided with a pair of first and second driver transistors of a first conductivity type and a pair of first and second load transistors of a second conductivity type forming a flip-flop circuit, and a pair of first and second access transistors, said memory cell comprising: a word line forming gate electrodes of said first and second access transistors; and a gate electrode of said first driver transistor and a gate electrode of said second driver transistor sharing one line extending in a direction parallel to said word line; wherein said first and second driver transistors have one common source region; said memory cell is formed in a rectangular region formed of first sides and second sides shorter than said first side; and first and second bit lines and a metal interconnection layer to be a ground line are formed a prescribed distance apart from each other and extending along the second side of said rectangular region, with said ground line extending between said first and second bit lines.
Claim 5
Dependent Claim 177 words
A semiconductor memory device including a memory cell provided with a pair of first and second driver transistors of a first conductivity type and a pair of first and second load transistors of a second conductivity type forming a flip-flop circuit, and a pair of first and second access transistors, said memory cell comprising: a word line forming gate electrodes of said first and second access transistors; and a gate electrode of said first driver transistor and a gate electrode of said second driver transistor sharing one line extending in a direction parallel to said word line; wherein said first and second driver transistors have one common source region; said memory cell is formed in a rectangular region formed of first sides and second sides shorter than said first side; and first and second bit lines and a metal interconnection layer to be a ground line are formed a prescribed distance apart from each other and extending along the second side of said rectangular region, with said ground line extending between said first and second bit lines.
Claim 6
Dependent Claim 109 words
A semiconductor memory device including a pair of first and second driver transistors of first type conductivity and a pair of first and second load transistors of second type conductivity forming a flipflop circuit, comprising: a word line forming the gate electrodes of first and second access transistors and extending in a prescribed direction; and a power supply voltage interconnection layer extending entirely in a direction substantially perpendicular to the direction in which said word line extends; wherein, the first and second load transistors are formed of thin film transistors and the power supply voltage interconnection layer serves as a line for supplying the power to the load transistors.
Claim 7
Dependent Claim 109 words
A semiconductor memory device including a pair of first and second driver transistors of first type conductivity and a pair of first and second load transistors of second type conductivity forming a flipflop circuit, comprising: a word line forming the gate electrodes of first and second access transistors and extending in a prescribed direction; and a power supply voltage interconnection layer extending entirely in a direction substantially perpendicular to the direction in which said word line extends; wherein, the first and second load transistors are formed of thin film transistors and the power supply voltage interconnection layer serves as a line for supplying the power to the load transistors.
Claim 8
Dependent Claim 102 words
A static random axis memory device comprising a memory cell formed in a rectangular region having first sides and second sides shorter than said first sides, with a ground line and first and second bit lines extending along the second side of said rectangular region, wherein said ground line extends between said first and second bit lines; said device comprising a first driver transistor, a second driver transistor and a word line, and a gate electrode of said first driver transistor and a gate electrode of said second driver transistor sharing one line extending in a direction parallel to said word line.
Claim 9
Dependent Claim 102 words
A static random axis memory device comprising a memory cell formed in a rectangular region having first sides and second sides shorter than said first sides, with a ground line and first and second bit lines extending along the second side of said rectangular region, wherein said ground line extends between said first and second bit lines; said device comprising a first driver transistor, a second driver transistor and a word line, and a gate electrode of said first driver transistor and a gate electrode of said second driver transistor sharing one line extending in a direction parallel to said word line.
Claim 10
Dependent Claim 169 words
A semiconductor memory device including a memory cell provided with a pair of first and second driver transistors of a first conductivity type and a pair of first and second load transistors of a second conductivity type forming a flip-flop circuit, and a pair of first and second access transistors, said memory cell comprising: a gate electrode of said first driver transistor extending in a predetermined direction; a gate electrode of said second driver transistor, extending substantially in the same direction as said gate electrode of said first driver transistor with a predetermined space therebetween; a word line extending substantially in the same direction as said gate electrode of said first driver transistor with a predetermined space therebetween, and forming gate electrodes of said first and second access transistors; and a low resistance layer formed on the substantially entire surfaces of source regions of said first and second driver transistors; wherein source regions of said first and second driver transistors are formed to be electrically connected to each other.
Claim 11
Dependent Claim 169 words
A semiconductor memory device including a memory cell provided with a pair of first and second driver transistors of a first conductivity type and a pair of first and second load transistors of a second conductivity type forming a flip-flop circuit, and a pair of first and second access transistors, said memory cell comprising: a gate electrode of said first driver transistor extending in a predetermined direction; a gate electrode of said second driver transistor, extending substantially in the same direction as said gate electrode of said first driver transistor with a predetermined space therebetween; a word line extending substantially in the same direction as said gate electrode of said first driver transistor with a predetermined space therebetween, and forming gate electrodes of said first and second access transistors; and a low resistance layer formed on the substantially entire surfaces of source regions of said first and second driver transistors; wherein source regions of said first and second driver transistors are formed to be electrically connected to each other.
Claim 12
Dependent Claim 18 words
The semiconductor memory device according to claim 6, wherein said low resistance layer includes a metal silicide layer.

References Cited (Backward Citations)

GB2049276A Cited
US4744056A Cited
JPS62245661A Cited
JPS63291461A Cited
JPH02122522A Cited
JPH0334569A Cited
EP0441379A2 Cited
JPH043976A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
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

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