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US5467302A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor memory device

Assignee: Panasonic Holdings Corp
•
Filing: 1994-12-12
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Granted: 1995-11-14
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Expires: 2014-12-12
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Abstract

Abstract Bit lines BL0 and /BL0 are connected to a sense amplifier SA0, the gate of a first MOS transistor to a first word line WL0, a first electrode of a first ferrodielectric capacitor Cs1 to the source of the first Qn, the drain of the first Qn to BL0, a second electrode of Cs1 to a first plate electrode CP0, the gate of a second MOS transistor Qn to a second word line DWL0, a first electrode of a second ferrodielectric capacitor Cd2 to the source of the second Qn, the drain of the second Qn to /BL0, and a second electrode of Cd1 to a second plate electrode DCP0, and after turning off the second Qn, the logic voltage of DCP0 is inverted. Hence, in a semiconductor memory device employing the ferrodielectric element, the dummy memory capacitor is initialized securely, and high speed reading is enabled without concentration of power consumption.

Inventors

  • 👤 Hiroshige Hirano
  • 👤 Tatsumi Sumi
  • 👤 Nobuyuki Moriwaki
  • 👤 George Nakane

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 10:36
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/22; G11C5/00; G11C5/06; G11C5/063

Claims Analysis

Total Claims: 37
Claim 1
Independent Claim 95 words
A semiconductor memory device comprising: a first electrode receiving a first logic voltage; a second electrode receiving a second logic voltage; main memory means for storing data, said main memory means having a first ferroelectric capacitor coupled to a first MOS transistor and said first electrode; dummy memory means for transferring data to and from said main memory means, said dummy memory means having a second capacitor coupled to a second MOS transistor and said second electrode; and means for inverting the logic voltage of the first electrode after turning off the second MOS transistor.
Claim 2
Dependent Claim 95 words
A semiconductor memory device comprising: a first electrode receiving a first logic voltage; a second electrode receiving a second logic voltage; main memory means for storing data, said main memory means having a first ferroelectric capacitor coupled to a first MOS transistor and said first electrode; dummy memory means for transferring data to and from said main memory means, said dummy memory means having a second capacitor coupled to a second MOS transistor and said second electrode; and means for inverting the logic voltage of the first electrode after turning off the second MOS transistor.
Claim 3
Dependent Claim 47 words
The semiconductor memory device of claim 1, further including means for (1) inverting the first logic voltage and the second logic voltage after turning off the second MOS transistor, and (2) turning off the first MOS transistor after the first electrode and the second electrode are inverted.
Claim 4
Dependent Claim 106 words
The semiconductor memory device of claim 1, further including: a first bit line coupled to the first NOS transistor; a second bit line coupled to the second MOS transistor; and means, (1) before one of (a) a start of writing and (b) a start of reading and (2) after one of (a) an end of writing, and (b) an end of reading of the main memory means, for (1) setting the second bit line at a certain logic voltage and activating the second MOS transistor, and (2) then setting the logic voltage of the second electrode at a reverse logic voltage of the certain logic voltage.
Claim 5
Dependent Claim 109 words
A semiconductor memory device comprising: an initializing control signal line; an initializing potential signal line; a first electrode having a first logic voltage; a second electrode having a second logic voltage; main memory means for storing data, said main memory means having a first ferroelectric capacitor coupled to a first MOS transistor and said first electrode; dummy memory means for transferring data to and from said main memory means, said dummy memory means having a second capacitor coupled to a second MOS transistor and said second electrode; and a third MOS transistor coupled to the initializing control signal line, the initializing potential signal line, and the second ferroelectric capacitor.
Claim 6
Dependent Claim 109 words
A semiconductor memory device comprising: an initializing control signal line; an initializing potential signal line; a first electrode having a first logic voltage; a second electrode having a second logic voltage; main memory means for storing data, said main memory means having a first ferroelectric capacitor coupled to a first MOS transistor and said first electrode; dummy memory means for transferring data to and from said main memory means, said dummy memory means having a second capacitor coupled to a second MOS transistor and said second electrode; and a third MOS transistor coupled to the initializing control signal line, the initializing potential signal line, and the second ferroelectric capacitor.
Claim 7
Dependent Claim 19 words
The semiconductor memory device of claim 4, wherein the initializing potential signal line is connected to a grounding potential.
Claim 8
Dependent Claim 62 words
The semiconductor memory device of claim 4, further including a first bit line coupled to the first MOS transistor; a second bit line coupled to the second MOS transistor; and means for setting said second bit line and said first bit line at a grounding potential before a start of one of (a) writing and (b) reading of the main memory means.
Claim 9
Dependent Claim 46 words
The semiconductor memory device of claim 4, further including means for (1) turning on the third MOS transistor after the second MOS transistor is turned off, and (2) turning off the first MOS transistor after the first logic voltage and the second logic voltage are inverted.
Claim 10
Dependent Claim 59 words
A semiconductor memory device of claim 1, further including a first bit line coupled to the first MOS transistor, said first bit line having a bit line logic voltage; and means for setting the first logic voltage of the first electrode at an inverse logic voltage of the bit line logic voltage before reading of the main memory means.
Claim 11
Dependent Claim 59 words
The semiconductor memory device of claim 4, further including a first bit line coupled to the first MOS transistor, said first bit line having a bit line logic voltage; and means for setting the first logic voltage of the first electrode at an inverse logic voltage of the bit line logic voltage before reading of the main memory means.
Claim 12
Dependent Claim 98 words
The semiconductor memory device of claim 1, wherein the second MOS transistor has a source coupled to the second ferroelectric capacitor and wherein said semiconductor memory device further includes a first bit line coupled to the first MOS transistor; a second bit line coupled to the second MOS transistor, said second bit line having a bit line logic voltage; and means for setting a source logic voltage at the source of the second MOS transistor and the second logic voltage at a inverse logic voltage of the bit line logic voltage before reading of the main memory means.
Claim 13
Dependent Claim 25 words
The semiconductor memory device of claim 8, wherein one of (a) the first logic voltage and (b) the second logic voltage is always the same.
Claim 14
Dependent Claim 25 words
The semiconductor memory device of claim 9, wherein one of (a) the first logic voltage and (b) the second logic voltage is always the same.
Claim 15
Dependent Claim 25 words
The semiconductor memory device of claim 10, wherein one of (a) the first logic voltage and (b) the second logic voltage is always the same.
Claim 16
Dependent Claim 98 words
The semiconductor memory device of claim 4, wherein the second MOS transistor has a source coupled to the second ferroelectric capacitor and wherein said semiconductor memory device further includes a first bit line coupled to the first MOS transistor; a second bit line coupled to the second MOS transistor, said second bit line having a bit line logic voltage; and means for setting a source logic voltage at the source of the second MOS transistor and the second logic voltage at a inverse logic voltage of the bit line logic voltage before reading of the main memory means.
Claim 17
Dependent Claim 103 words
The semiconductor memory device of claim 1, wherein the second MOS transistor has a source coupled to the second ferroelectric capacitor and a source logic voltage at the source of the second MOS transistor; and wherein the semiconductor memory device further includes a first bit line coupled to the first MOS transistor; a second bit line coupled to the second MOS transistor, said second bit line having a bit line logic voltage; and means for setting the bit line logic voltage and the second logic voltage at an inverse logic voltage of the source logic voltage before reading of the main memory means.
Claim 18
Dependent Claim 103 words
The semiconductor memory device of claim 4, wherein the second MOS transistor has a source coupled to the second ferroelectric capacitor and a source logic voltage at the source of the second MOS transistor; and wherein the semiconductor memory device further includes a first bit line coupled to the first MOS transistor; a second bit line coupled to the second MOS transistor, said second bit line having a bit line logic voltage; and means for setting the bit line logic voltage and the second logic voltage at an inverse logic voltage of the source logic voltage before reading of the main memory means.
Claim 19
Dependent Claim 41 words
The semiconductor memory device of claim 1, further including means for inverting the first logic voltage of the first electrode and the second logic voltage of the second electrode after turning on the first MOS transistor and the second MOS transistor.
Claim 20
Dependent Claim 41 words
The semiconductor memory device of claim 4, further including means for inverting the first logic voltage of the first electrode and the second logic voltage of the second electrode after turning on the first MOS transistor and the second MOS transistor.
Claim 21
Dependent Claim 95 words
The semiconductor memory device of claim 1, further including a first bit line coupled to the first NOS transistor; a second bit line coupled to the second MOS transistor; and means for (a) pre-charging the first line and the second bit line after turning on the first MOS transistor and the second MOS transistor, (b) terminating the pre-charging before a start of one of (a) reading and (b) writing of the main memory means, and (c) then inverting the first logic voltage of the first electrode and the second logic voltage of the second electrode.
Claim 22
Dependent Claim 95 words
The semiconductor memory device of claim 4, further including a first bit line coupled to the first NOS transistor; a second bit line coupled to the second MOS transistor; and means for (a) pre-charging the first line and the second bit line after turning on the first MOS transistor and the second MOS transistor, (b) terminating the pre-charging before a start of one of (a) reading and (b) writing of the main memory means, and (c) then inverting the first logic voltage of the first electrode and the second logic voltage of the second electrode.
Claim 23
Dependent Claim 35 words
The semiconductor memory device of claim 4, further including means for turning on the first MOS transistor and the second MOS transistor after inverting the logic voltages of the first electrode and the second electrode.
Claim 24
Dependent Claim 35 words
The semiconductor memory device of claim 1, further including means for turning on the first MOS transistor and the second MOS transistor after inverting the logic voltages of the first electrode and the second electrode.
Claim 25
Dependent Claim 17 words
The semiconductor memory device of claim 1, wherein the first electrode is coupled to the second electrode.
Claim 26
Dependent Claim 62 words
A semiconductor memory device comprising: an electrode; main memory means for storing data, said main memory means having a first ferroelectric capacitor coupled to a first MOS transistor and said electrode; and dummy memory means for transferring data to and from said main memory means, said dummy memory means having a second capacitor coupled to a second MOS transistor and said electrode.
Claim 27
Dependent Claim 62 words
A semiconductor memory device comprising: an electrode; main memory means for storing data, said main memory means having a first ferroelectric capacitor coupled to a first MOS transistor and said electrode; and dummy memory means for transferring data to and from said main memory means, said dummy memory means having a second capacitor coupled to a second MOS transistor and said electrode.
Claim 28
Dependent Claim 174 words
A semiconductor memory device comprising: an amplifier, a first word line and a second word line, a first bit line and a second bit line connected to the amplifier, a first plate electrode and a second plate electrode, a first ferroelectric capacitor having a first electrode and a second electrode, the second electrode coupled to the first plate electrode, a first MOS transistor having a gate coupled to the first word line, a source coupled to the first electrode of the first ferroelectric capacitor, and a drain coupled to the first bit line, a second ferroelectric capacitor having a first electrode and a second electrode, the second electrode couple to the second plate electrode, and a second MOS transistor having a gate coupled to the second word line, a source coupled to the first electrode of the second ferroelectric capacitor, and a drain coupled to the second bit line wherein the electric field between the first electrode and the second electrode of the second ferroelectric capacitor is always in a first direction including zero.
Claim 29
Dependent Claim 174 words
A semiconductor memory device comprising: an amplifier, a first word line and a second word line, a first bit line and a second bit line connected to the amplifier, a first plate electrode and a second plate electrode, a first ferroelectric capacitor having a first electrode and a second electrode, the second electrode coupled to the first plate electrode, a first MOS transistor having a gate coupled to the first word line, a source coupled to the first electrode of the first ferroelectric capacitor, and a drain coupled to the first bit line, a second ferroelectric capacitor having a first electrode and a second electrode, the second electrode couple to the second plate electrode, and a second MOS transistor having a gate coupled to the second word line, a source coupled to the first electrode of the second ferroelectric capacitor, and a drain coupled to the second bit line wherein the electric field between the first electrode and the second electrode of the second ferroelectric capacitor is always in a first direction including zero.
Claim 30
Dependent Claim 44 words
The semiconductor memory device as recited in claim 1, wherein an electric field is formed between the first electrode and the second electrode of the second ferroelectric capacitor, said electric field is oriented in a first direction when the second MOS transistor is activated.
Claim 31
Dependent Claim 60 words
The semiconductor memory device as recited in claim 1, wherein an electric potential is formed between the first electrode and the second electrode of the second ferroelectric capacitor and wherein the second MOS transistor is activated after the electric potential between the first electrode and the second electrode of the second ferroelectric capacitor is changed to a different electric potential.
Claim 32
Dependent Claim 28 words
The semiconductor memory device as recited in claim 1, wherein the second plate electrode has an electric potential which is changed after the second MOS transistor is activated.
Claim 33
Dependent Claim 37 words
The semiconductor memory device recited in claim 1, wherein the second plate electrode has an electric potential and wherein the second MOS transistor is turned on after the electric potential of the second plate electrode is changed.
Claim 34
Dependent Claim 210 words
A semiconductor memory device comprising: an amplifier, a first word line and a second word line, a first plate electrode and a second plate electrode, a first bit line and a second bit line connected to the amplifier, a first ferroelectric capacitor having a first electrode and a second electrode, the second electrode coupled to the first plate electrode, a first MOS transistor having a gate coupled to the first word line, a source coupled to the first electrode of the first ferroelectric capacitor, and a drain coupled to the first bit line, a second ferroelectric capacitor having a first electrode and a second electrode, the second electrode coupled to the first plate electrode, and a second MOS transistor having a gate coupled to a second word line, a source coupled to the first electrode of the second ferroelectric capacitor, and a drain coupled to the second bit line, an electric field formed between the first bit line and the second electrode of the first ferroelectric capacitor so that the electric field is (a) oriented in a first direction when the first MOS transistor is activated and (b) oriented in a second direction before the first MOS transistor is deactivated, said first direction is the opposite of said second direction.
Claim 35
Dependent Claim 210 words
A semiconductor memory device comprising: an amplifier, a first word line and a second word line, a first plate electrode and a second plate electrode, a first bit line and a second bit line connected to the amplifier, a first ferroelectric capacitor having a first electrode and a second electrode, the second electrode coupled to the first plate electrode, a first MOS transistor having a gate coupled to the first word line, a source coupled to the first electrode of the first ferroelectric capacitor, and a drain coupled to the first bit line, a second ferroelectric capacitor having a first electrode and a second electrode, the second electrode coupled to the first plate electrode, and a second MOS transistor having a gate coupled to a second word line, a source coupled to the first electrode of the second ferroelectric capacitor, and a drain coupled to the second bit line, an electric field formed between the first bit line and the second electrode of the first ferroelectric capacitor so that the electric field is (a) oriented in a first direction when the first MOS transistor is activated and (b) oriented in a second direction before the first MOS transistor is deactivated, said first direction is the opposite of said second direction.
Claim 36
Dependent Claim 290 words
A semiconductor memory device comprising: an amplifier, a first word line and a second word line, a first plate electrode and a second plate electrode, a first bit line and a second bit line connected to the amplifier, a first ferroelectric capacitor having a first electrode and a second electrode, the second electrode of the first ferroelectric capacitor coupled to the first plate electrode, a first MOS transistor having a gate coupled to the first word line, a source coupled to the first electrode of the first ferroelectric capacitor, and a drain coupled to the first bit line, a second ferroelectric capacitor having a first electrode and a second electrode, and the second electrode of the second ferroelectric capacitor coupled to the second plate electrode, a second MOS transistor having a gate coupled to the second word line, a source coupled to the first electrode of the second ferroelectric capacitor, and a drain coupled to the second bit line, a first electric field formed between the first bit line and the second electrode of the first ferroelectric capacitor so that the electric field is oriented in a first direction when the first MOS transistor is activated and orientated in a second direction before the first MOS transistor and the second MOS transistors are deactivated, said first electric field and said second electric field are oriented in opposite directions, and a second electric field formed between the second bit line and the second electrode of the second ferroelectric capacitor so that the second electric field is orientated in a third direction when the second MOS transistor is activated and the second electric field is oriented in the third direction after the first MOS transistor and the second MOS transistors are deactivated.
Claim 37
Dependent Claim 290 words
A semiconductor memory device comprising: an amplifier, a first word line and a second word line, a first plate electrode and a second plate electrode, a first bit line and a second bit line connected to the amplifier, a first ferroelectric capacitor having a first electrode and a second electrode, the second electrode of the first ferroelectric capacitor coupled to the first plate electrode, a first MOS transistor having a gate coupled to the first word line, a source coupled to the first electrode of the first ferroelectric capacitor, and a drain coupled to the first bit line, a second ferroelectric capacitor having a first electrode and a second electrode, and the second electrode of the second ferroelectric capacitor coupled to the second plate electrode, a second MOS transistor having a gate coupled to the second word line, a source coupled to the first electrode of the second ferroelectric capacitor, and a drain coupled to the second bit line, a first electric field formed between the first bit line and the second electrode of the first ferroelectric capacitor so that the electric field is oriented in a first direction when the first MOS transistor is activated and orientated in a second direction before the first MOS transistor and the second MOS transistors are deactivated, said first electric field and said second electric field are oriented in opposite directions, and a second electric field formed between the second bit line and the second electrode of the second ferroelectric capacitor so that the second electric field is orientated in a third direction when the second MOS transistor is activated and the second electric field is oriented in the third direction after the first MOS transistor and the second MOS transistors are deactivated.

References Cited (Backward Citations)

DE4110407A1 Cited
DE4118847A1 Cited
US5381364A Cited

USPTO Annuity & Maintenance Windows

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