US6853587B2
Expired / Lapsed
US
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Vertical NROM having a storage density of 1 bit per 1F2
Assignee: Micron Technology Inc
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Filing: 2002-06-21
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Granted: 2005-02-08
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Expires: 2022-06-21
Abstract
Abstract Structures and methods for vertical memory cell. The vertical memory cell includes a vertical metal oxide semiconductor field effect transistor (MOSFET) extending outwardly from a substrate. The MOSFET has a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator. A first transmission line is coupled to the first source/drain region. A second transmission line is coupled to the second source/drain region. The MOSFET is adapted to be programmed to have a charge trapped in at least one of a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region.
Inventors
- 👤 Leonard Forbes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:20
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/031; H10D64/037; B; B82; B82Y; B82Y10/00; G; G11; G11C; G11C16/00; G11C16/02; G11C16/04; G11C16/0466; G11C16/0475; H10B; H10B12/00; H10B12/01; H10B12/09; H10B12/50; H10B43/00; H10B43/30; H10B69/00; H10D30/00; H10D30/01; H10D30/021; H10D30/0413; H10D30/60; H10D30/69; H10D30/691; H10D30/693
Claims Analysis
Total Claims: 71
Claim 1
Independent Claim
153 words
A vertical multiple bit cell, comprising: a vertical metal oxide semiconductor field effect transistor (MOSFET) extending outwardly from a substrate, the MOSFET having a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator; a first transmission line coupled to the first source/drain region; and a second transmission line coupled to the second source/drain region; wherein the MOSFET is a programmed MOSFET having a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the programmed MOSFET operates at reduced drain source current; and wherein both the first and second source/drain regions of the MOSFET share a source/drain region with a second MOSFET.
Claim 2
Dependent Claim
153 words
A vertical multiple bit cell, comprising: a vertical metal oxide semiconductor field effect transistor (MOSFET) extending outwardly from a substrate, the MOSFET having a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator; a first transmission line coupled to the first source/drain region; and a second transmission line coupled to the second source/drain region; wherein the MOSFET is a programmed MOSFET having a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the programmed MOSFET operates at reduced drain source current; and wherein both the first and second source/drain regions of the MOSFET share a source/drain region with a second MOSFET.
Claim 3
Dependent Claim
73 words
The multiple bit cell of claim 1 , wherein the first source/drain region of the MOSFET serves as a source region and the second source/drain region of the MOSFET serves as a drain region in a first mode of operation and wherein the first source/drain region of the MOSFET serves as a drain region and the second source/drain region of the MOSFET serves as a source region in a second mode of operation.
Claim 4
Dependent Claim
18 words
The multiple bit cell of claim 1 , wherein the first transmission line includes a buried bit line.
Claim 5
Dependent Claim
26 words
The multiple bit cell of claim 1 , wherein the MOSFET includes a charge programmed in both the first storage region and the second storage region.
Claim 6
Dependent Claim
31 words
The multiple bit cell of claim 1 , wherein the first storage region is adjacent the first source/drain region, and wherein the second storage region is adjacent the second source/drain region.
Claim 7
Dependent Claim
54 words
The multiple bit cell of claim 5 , wherein the charge programmed in the at least one of the first charge storage region and the second storage region creates a high voltage threshold when the MOSFET is operated with the adjacent first source/drain region or the second source/drain region serving as the source region.
Claim 8
Dependent Claim
20 words
The multiple bit cell of claim 1 , wherein the gate insulator has a thickness of approximately 10 nanometers (nm).
Claim 9
Dependent Claim
47 words
The multiple bit cell of claim 7 , wherein the gate insulator includes a gate insulator selected from the group of silicon dioxide (SiO 2 ) formed by wet oxidation, silicon oxynitride (SON), silicon rich oxide (SRO), and silicon rich aluminum oxide (Al 2 O 3 ).
Claim 10
Dependent Claim
192 words
A vertical multiple bit cell, comprising: a vertical metal oxide semiconductor field effect transistor (MOSFET) extending outwardly from a substrate, the MOSEET having a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator; a wordline coupled to the gate; a first transmission line coupled to the first source/drain region; and a second transmission line coupled to the second source/drain region; wherein the MOSFET is a programmed MOSFET having a charge programmed both a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the channel region has a first voltage threshold region (Vt1) adjacent to the first source/drain region a second voltage threshold region (Vt2) adjacent to the second source/drain region which vary depending on in which direction the MOSFET is operated; and wherein the first source/drain region and the second source/drain region of the MOSFET share a first and a second source/drain region respectively from a second MOSFET.
Claim 11
Dependent Claim
192 words
A vertical multiple bit cell, comprising: a vertical metal oxide semiconductor field effect transistor (MOSFET) extending outwardly from a substrate, the MOSEET having a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator; a wordline coupled to the gate; a first transmission line coupled to the first source/drain region; and a second transmission line coupled to the second source/drain region; wherein the MOSFET is a programmed MOSFET having a charge programmed both a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the channel region has a first voltage threshold region (Vt1) adjacent to the first source/drain region a second voltage threshold region (Vt2) adjacent to the second source/drain region which vary depending on in which direction the MOSFET is operated; and wherein the first source/drain region and the second source/drain region of the MOSFET share a first and a second source/drain region respectively from a second MOSFET.
Claim 12
Dependent Claim
67 words
The multiple bit cell of claim 9 , wherein, the second voltage threshold region (Vt2) in the channel is adjacent the first source/drain region, and wherein the first voltage threshold region (Vt1) in the channel is adjacent the second source/drain region, and wherein Vt2 has a higher voltage threshold than the Vt1 when the MOSFET is operated with the first source/drain region serving as the source region.
Claim 13
Dependent Claim
20 words
The multiple bit cell of claim 9 , wherein the gate insulator has a thickness of approximately 10 nanometers (nm).
Claim 14
Dependent Claim
49 words
The multiple bit cell of claim 9 , wherein the gate insulator includes a gate insulator selected from the group of silicon rich aluminum oxide insulators, silicon rich oxides with inclusions of nanoparticles of silicon, silicon oxide insulators with inclusions of nanoparticles of silicon carbide, and silicon oxycarbide insulators.
Claim 15
Dependent Claim
16 words
The multiple bit cell of claim 9 , wherein the gate insulator includes a composite layer.
Claim 16
Dependent Claim
37 words
The multiple bit cell of claim 13 , wherein the composite layer includes a composite layer selected from the group of an oxide-aluminum oxide (Al 2 O 3 )— oxide composite layer, and oxide-silicon oxycarbide-oxide composite layer.
Claim 17
Dependent Claim
38 words
The multiple bit cell of claim 13 , wherein the composite layer includes a composite layer, or a non-stoichiometric single layer of two or more materials selected from the group of silicon (Si), titanium (Ti), and tantalum (Ta).
Claim 18
Dependent Claim
19 words
The multiple bit cell of claim 9 , wherein the gate insulator includes a multiple layer of oxide-nitride-oxide (ONO).
Claim 19
Dependent Claim
216 words
A memory array, comprising: a number of vertical multiple bit cells extending from a substrate and separated by trenches, wherein each vertical multiple bit cell includes a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator; a number of first data lines coupled to the second source/drain region of each multiple bit cell along columns of the memory array; a number of word lines coupled to the gate of each multiple bit cell along rows of the memory array; and a number of second data lines coupled to the first source/drain region of each multiple bit cell along columns of the memory array; wherein at least one of the multiple bit cells is a programmed MOSFET having a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the programmed MOSFET operates at reduced drain source current and wherein the first and second source/drain regions of the MOSFET share both the first and second source/drain regions respectively from another of the vertical multiple bit cells.
Claim 20
Dependent Claim
216 words
A memory array, comprising: a number of vertical multiple bit cells extending from a substrate and separated by trenches, wherein each vertical multiple bit cell includes a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator; a number of first data lines coupled to the second source/drain region of each multiple bit cell along columns of the memory array; a number of word lines coupled to the gate of each multiple bit cell along rows of the memory array; and a number of second data lines coupled to the first source/drain region of each multiple bit cell along columns of the memory array; wherein at least one of the multiple bit cells is a programmed MOSFET having a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the programmed MOSFET operates at reduced drain source current and wherein the first and second source/drain regions of the MOSFET share both the first and second source/drain regions respectively from another of the vertical multiple bit cells.
Claim 21
Dependent Claim
20 words
The multiple bit cell of claim 17 , wherein the number of second data lines include a buried data lines.
Claim 22
Dependent Claim
26 words
The multiple bit cell of claim 17 , wherein the MOSFET includes a charge programmed in both the first storage region and the second storage region.
Claim 23
Dependent Claim
31 words
The multiple bit cell of claim 17 , wherein the first storage region is adjacent the first source/drain region, and wherein the second storage region is adjacent the second source/drain region.
Claim 24
Dependent Claim
54 words
The multiple bit cell of claim 20 , wherein the charge programmed in the at least one of the first charge storage region and the second storage region creates a high voltage threshold when the MOSFET is operated with the adjacent first source/drain region or the second source/drain region serving as the source region.
Claim 25
Dependent Claim
24 words
The memory array of claim 17 , wherein the gate insulator of each multiple bit cell has a thickness of approximately 10 nanometers (nm).
Claim 26
Dependent Claim
37 words
The memory array of claim 17 , wherein the gate insulator includes a gate insulator selected from the group of silicon dioxide (SiO 2 ) formed by wet oxidation, silicon oxynitride (SON), and silicon rich aluminum oxide.
Claim 27
Dependent Claim
36 words
The memory array of claim 17 , wherein the number of vertical multiple bit cells extending from a substrate operate as equivalent to a transistor having a size of 1.0 photolithographic feature squared (1F 2 ).
Claim 28
Dependent Claim
297 words
A memory array, comprising: a number of vertical pillars formed in rows and columns extending outwardly from a substrate and separated by a number of trenches, wherein the number of vertical pillars serve as transistors including a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator in the trenches along columns of pillars, wherein each transistor has an area of two photolithograpic features squared (2F 2 ) and can store two bits such that a data storage density for each transistor is one bit for each one photolithograpic feature squared (1F 2 ); a number of first transmission lines coupled to the second source/drain region of each transistor along columns of the memory array; a number of word lines coupled to the gate of each transistor along rows of the memory array; and a number of second transmission lines coupled to the first source/drain region of each transistor along columns of the memory array; wherein at least one of multiple bit cell transistors is a programmed MOSFET having a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the channel region has a first voltage threshold region (Vt1) adjacent to the first source/drain region a second voltage threshold region (Vt2) adjacent to the second source/drain region which vary depending on in which direction the MOSFET is operated and wherein the first and second source/drain regions of the MOSFET share both the first and second source/drain regions respectively from another of the multiple bit cell transistors.
Claim 29
Dependent Claim
297 words
A memory array, comprising: a number of vertical pillars formed in rows and columns extending outwardly from a substrate and separated by a number of trenches, wherein the number of vertical pillars serve as transistors including a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator in the trenches along columns of pillars, wherein each transistor has an area of two photolithograpic features squared (2F 2 ) and can store two bits such that a data storage density for each transistor is one bit for each one photolithograpic feature squared (1F 2 ); a number of first transmission lines coupled to the second source/drain region of each transistor along columns of the memory array; a number of word lines coupled to the gate of each transistor along rows of the memory array; and a number of second transmission lines coupled to the first source/drain region of each transistor along columns of the memory array; wherein at least one of multiple bit cell transistors is a programmed MOSFET having a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the channel region has a first voltage threshold region (Vt1) adjacent to the first source/drain region a second voltage threshold region (Vt2) adjacent to the second source/drain region which vary depending on in which direction the MOSFET is operated and wherein the first and second source/drain regions of the MOSFET share both the first and second source/drain regions respectively from another of the multiple bit cell transistors.
Claim 30
Dependent Claim
67 words
The multiple bit cell of claim 25 , wherein, the second voltage threshold region (Vt2) in the channel is adjacent the first source/drain region, and wherein the first voltage threshold region (Vt1) in the channel is adjacent the second source/drain region, and wherein Vt1 has a higher voltage threshold than the Vt2 when the MOSFET is operated with the second source/drain region serving as the source region.
Claim 31
Dependent Claim
20 words
The multiple bit cell of claim 25 , wherein the number of first transmission lines include a buried data lines.
Claim 32
Dependent Claim
26 words
The multiple bit cell of claim 25 , wherein the MOSFET includes a charge programmed in both the first storage region and the second storage region.
Claim 33
Dependent Claim
31 words
The multiple bit cell of claim 25 , wherein the first storage region is adjacent the first source/drain region, and wherein the second storage region is adjacent the second source/drain region.
Claim 34
Dependent Claim
55 words
The multiple bit cell of claim 29 , wherein the charge programmed in the at least one of the first charge storage region and the second storage region creates a high voltage threshold when the MOSFET is operated with the an adjacent first source/drain region or the second source/drain region serving as the source region.
Claim 35
Dependent Claim
301 words
An electronic system, comprising: a processor; and a memory device coupled to the processor, wherein the memory device includes a memory array, the memory array including; a number of vertical transistors extending outwardly from a substrate and separated by trenches, wherein each transistor includes a first source/drain region, a second source/drain region, a channel region between the source and the drain regions, and a gate separated from the channel region by a gate insulator; a number of first transmission lines coupled to the second source/drain region of each vertical transistor along columns of the memory array; a number of wordlines coupled to the gate of each vertical transistor along rows of the memory array; a number of second transmission lines coupled to the first source/drain region of each vertical transistor along columns of the memory array; a wordline address decoder coupled to the number of wordlines; a first address decoder coupled to the number of first transmission lines; a second address decoder coupled to the number of second transmission lines; and a sense amplifier coupled to the first and the second number of transmission lines; wherein at least one of the transistors is a programmed MOSFET having a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the channel region has a first voltage threshold region (Vt1) adjacent to the first source/drain region a second voltage threshold region (Vt2) adjacent to the second source/drain region which vary depending on in which direction the MOSFET is operated; and wherein the first and second source/drain regions of the MOSFET share the first and second source/drain regions respectively from another of the transistors.
Claim 36
Dependent Claim
301 words
An electronic system, comprising: a processor; and a memory device coupled to the processor, wherein the memory device includes a memory array, the memory array including; a number of vertical transistors extending outwardly from a substrate and separated by trenches, wherein each transistor includes a first source/drain region, a second source/drain region, a channel region between the source and the drain regions, and a gate separated from the channel region by a gate insulator; a number of first transmission lines coupled to the second source/drain region of each vertical transistor along columns of the memory array; a number of wordlines coupled to the gate of each vertical transistor along rows of the memory array; a number of second transmission lines coupled to the first source/drain region of each vertical transistor along columns of the memory array; a wordline address decoder coupled to the number of wordlines; a first address decoder coupled to the number of first transmission lines; a second address decoder coupled to the number of second transmission lines; and a sense amplifier coupled to the first and the second number of transmission lines; wherein at least one of the transistors is a programmed MOSFET having a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and operated with either the first source/drain region or the second source/drain region serving as the source region such that the channel region has a first voltage threshold region (Vt1) adjacent to the first source/drain region a second voltage threshold region (Vt2) adjacent to the second source/drain region which vary depending on in which direction the MOSFET is operated; and wherein the first and second source/drain regions of the MOSFET share the first and second source/drain regions respectively from another of the transistors.
Claim 37
Dependent Claim
66 words
The electronic system of claim 31 , wherein, the second voltage threshold region (Vt2) in the channel is adjacent the first source/drain region, and wherein the first voltage threshold region (Vt1) in the channel is adjacent the second source/drain region, and wherein Vt1 has a higher voltage threshold than the Vt2 when the MOSFET is operated with the second source/drain region serving as the source region.
Claim 38
Dependent Claim
19 words
The electronic system of claim 31 , wherein the number of first transmission lines include a buried data lines.
Claim 39
Dependent Claim
25 words
The electronic system of claim 31 , wherein the MOSFET includes a charge programmed in both the first storage region and the second storage region.
Claim 40
Dependent Claim
30 words
The electronic system of claim 31 , wherein the first storage region is adjacent the first source/drain region, and wherein the second storage region is adjacent the second source/drain region.
Claim 41
Dependent Claim
54 words
The electronic system of claim 35 , wherein the charge programmed in the at least one of the first charge storage region and the second storage region creates a high voltage threshold when the MOSFET is operated with the an adjacent first source/drain region or the second source/drain region serving as the source region.
Claim 42
Dependent Claim
40 words
The electronic system of claim 31 , wherein the gate insulator of each transistor includes a gate insulator selected from the group of silicon dioxide (SiO 2 ) formed by wet oxidation, silicon oxynitride (SON), and silicon rich aluminum oxide.
Claim 43
Dependent Claim
19 words
The electronic system of claim 37 , wherein the gate insulator of each transistor includes an oxide-nitride-oxide (ONO) insulator.
Claim 44
Dependent Claim
31 words
The electronic system of claim 31 , wherein each transistor transistors operate as equivalent to a transistor having a size of much less than 1.0 lithographic feature squared (1F 2 ).
Claim 45
Independent Claim
253 words
A method for operating a memory, comprising: programming one or more vertical MOSFETs extending outwardly from a substrate in a DRAM array to have a storage density of one bit per one photolithographic feature squared unit area, wherein each MOSFET in the DRAM array includes a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator, wherein the first and second source/drain regions of a first MOSFET share the first and second source/drain regions of a second MOSFET, and wherein programming the one or more vertical MOSFETs includes programming the one or more vertical MOSFETs in a first and a second direction, wherein programming in a first and a second direction includes: applying a first voltage potential to a first source/drain region of the vertical MOSFET; applying a second voltage potential to a second source/drain region of the vertical MOSFET; applying a gate potential to a gate of the vertical MOSFET; and wherein applying the first, second and gate potentials to the one or more vertical MOSFETs includes creating a hot electron injection into the gate insulator of the one or more MOSFETs such that a programmed MOSFET has a charge programmed in at least one of a first storage region and a second storage region in the gate insulator, and the programmed MOSFET can be operated with either the first source/drain region or the second source/drain region serving as the source region.
Claim 46
Independent Claim
253 words
A method for operating a memory, comprising: programming one or more vertical MOSFETs extending outwardly from a substrate in a DRAM array to have a storage density of one bit per one photolithographic feature squared unit area, wherein each MOSFET in the DRAM array includes a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator, wherein the first and second source/drain regions of a first MOSFET share the first and second source/drain regions of a second MOSFET, and wherein programming the one or more vertical MOSFETs includes programming the one or more vertical MOSFETs in a first and a second direction, wherein programming in a first and a second direction includes: applying a first voltage potential to a first source/drain region of the vertical MOSFET; applying a second voltage potential to a second source/drain region of the vertical MOSFET; applying a gate potential to a gate of the vertical MOSFET; and wherein applying the first, second and gate potentials to the one or more vertical MOSFETs includes creating a hot electron injection into the gate insulator of the one or more MOSFETs such that a programmed MOSFET has a charge programmed in at least one of a first storage region and a second storage region in the gate insulator, and the programmed MOSFET can be operated with either the first source/drain region or the second source/drain region serving as the source region.
Claim 47
Dependent Claim
86 words
The method of claim 40 , wherein when programming in a first direction, applying a first voltage potential to the first source/drain region of the vertical MOSFET includes grounding the first source/drain region of the vertical MOSFET, applying a second voltage potential to the second source/drain region includes applying a high voltage potential (VDD) to the second source/drain region, and applying a gate potential to the gate in order to create a conduction channel between the first and the second source/drain regions of the vertical MOSFET.
Claim 48
Dependent Claim
65 words
The method of claim 41 , wherein the method further includes reading one or more vertical MOSFETs in the DRAM array in a first direction, wherein reading one or more vertical MOSFETs in the first direction includes: grounding the second source/drain region; precharging the first source/drain region to a fractional voltage of VDD; and applying a gate potential of approximately 1.0 Volt to the gate.
Claim 49
Dependent Claim
102 words
The method of claim 42 , wherein when programming in a first direction, creating a hot electron injection into the gate insulator of the one or more vertical MOSFETs includes trapping a charge in the first storage region in the gate insulator adjacent to the second source/drain region such that when the MOSFET is read in the first direction the MOSFET has a first threshold voltage region (Vt1) adjacent to the first source/drain region and a second threshold voltage region (Vt2) adjacent to the second source/drain region, wherein Vt2 is greater than Vt1 and the MOSFET operates at reduced drain source current.
Claim 50
Dependent Claim
42 words
The method of claim 43 , wherein trapping a charge in the gate insulator adjacent to the second source/drain region includes increasing a normal threshold voltage in the Vt2 by approximately 0.5 Volts when the MOSFET is read in the first direction.
Claim 51
Dependent Claim
74 words
The method of claim 44 , wherein reading the one or more MOSFETs in the first and the second directions includes using a sense amplifier to detect a change in an integrated drain current, and wherein when read in a first direction the MOSFET will exhibit a change in an integrated drain current of approximately 12.5 μA when addressed over approximately 10 ns when no charge is programmed in the first charge storage region.
Claim 52
Dependent Claim
86 words
The method of claim 40 , wherein when programming in a second direction, applying a first voltage potential to the first source/drain region of the vertical MOSFET includes applying a high voltage potential (VDD) to the first source/drain region of the vertical MOSFET, applying a second voltage potential to the second source/drain region includes grounding the second source/drain region, and applying a gate potential to the gate in order to create a conduction channel between the first and the second source/drain regions of the vertical MOSFET.
Claim 53
Dependent Claim
65 words
The method of claim 46 , wherein the method further includes reading one or more vertical MOSFETs in the DRAM array in a second direction, wherein reading one or more vertical MOSFETs in the second direction includes: grounding the first source/drain region; precharging the second source/drain region to a fractional voltage of VDD; and applying a gate potential of approximately 1.0 Volt to the gate.
Claim 54
Dependent Claim
102 words
The method of claim 47 , wherein when programming in a second direction, creating a hot electron injection into the gate insulator of the one or more vertical MOSFETs includes trapping a charge in the second storage region in the gate insulator adjacent to the first source/drain region such that when the MOSFET is read in the second direction the MOSFET has a first threshold voltage region (Vt1) adjacent to the first source/drain region and a second threshold voltage region (Vt2) adjacent to the second source/drain region, wherein Vt1 is greater than Vt2 and the MOSFET operates at reduced drain source current.
Claim 55
Dependent Claim
42 words
The method of claim 48 , wherein trapping a charge in the gate insulator adjacent to the first source/drain region includes increasing a normal threshold voltage in the Vt1 by approximately 0.5 Volts when the MOSFET is read in the first direction.
Claim 56
Dependent Claim
74 words
The method of claim 49 , wherein reading the one or more MOSFETs in the first and the second directions includes using a sense amplifier to detect a change in an integrated drain current, and wherein when read in a second direction the MOSFET will exhibit a change in an integrated drain current of approximately 12.5 μA when addressed over approximately 10 ns when no charge is programmed in the second charge storage region.
Claim 57
Independent Claim
181 words
A method for forming a memory, comprising: forming a vertical multiple bit cell, wherein forming the vertical multiple bit cell includes; forming a vertical metal oxide semiconductor field effect transistor (MOSFET) extending outwardly from a substrate, the MOSFET having a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator, wherein the first and second source/drain regions of the MOSFET share the first and second source/drain regions of a second MOSFET respectively; forming a first transmission line coupled to the first source/drain region; forming a second transmission line coupled to the second source/drain region; and wherein forming the MOSFET includes forming a MOSFET adapted to be programmable to have a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and to be operated with either the first source/drain region or the second source/drain region serving as the source region such that the programmed MOSFET operates at reduced drain source current.
Claim 58
Independent Claim
181 words
A method for forming a memory, comprising: forming a vertical multiple bit cell, wherein forming the vertical multiple bit cell includes; forming a vertical metal oxide semiconductor field effect transistor (MOSFET) extending outwardly from a substrate, the MOSFET having a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator, wherein the first and second source/drain regions of the MOSFET share the first and second source/drain regions of a second MOSFET respectively; forming a first transmission line coupled to the first source/drain region; forming a second transmission line coupled to the second source/drain region; and wherein forming the MOSFET includes forming a MOSFET adapted to be programmable to have a charge programmed in at least one of a first storage region and a second storage region in the gate insulator and to be operated with either the first source/drain region or the second source/drain region serving as the source region such that the programmed MOSFET operates at reduced drain source current.
Claim 59
Dependent Claim
81 words
The method of claim 51 , wherein forming the MOSFET includes forming the MOSFET such that the first source/drain region of the MOSFET serves as a source region and the second source/drain region of the MOSFET serves as a drain region in a first mode of operation, and such that the first source/drain region of the MOSFET serves as a drain region and the second source/drain region of the MOSFET serves as a source region in a second mode of operation.
Claim 60
Independent Claim
17 words
The method of claim Si, wherein forming the first transmission line includes forming a buried bit line.
Claim 61
Dependent Claim
33 words
The method of claim 51 , wherein forming the MOSFET includes forming a MOSFET adapted to be programmed to have charge trapped in both the first storage region and the second storage region.
Claim 62
Dependent Claim
39 words
The method of claim 51 , wherein forming the MOSFET includes forming the MOSFET such that the first storage region is adjacent the second source/drain region, and such that the second storage region is adjacent the first source/drain region.
Claim 63
Dependent Claim
72 words
The method of claim 51 , wherein forming the MOSFET includes forming the MOSFET such that the charge programmed in the at least one of the first charge storage region and the second storage region creates a high voltage threshold and operates at a reduced drain source current when the MOSFET is operated with an adjacent one of the first source/drain region or the second source/drain region serving as the source region.
Claim 64
Dependent Claim
27 words
The method of claim 51 , wherein forming the MOSFET includes forming the MOSFET such that the gate insulator has a thickness of approximately 10 nanometers (nm).
Claim 65
Dependent Claim
49 words
The method of claim 51 , wherein forming the MOSFET includes forming the MOSFET with a gate insulator selected from the group of silicon dioxide (SiO 2 ) formed by wet oxidation, silicon oxynitride (SON), silicon rich oxide (SRO), and silicon rich aluminum oxide (Al 2 O 3 ).
Claim 66
Dependent Claim
51 words
The method of claim 51 , wherein forming the MOSFET includes forming the MOSFET with a gate insulator selected from the group of silicon rich aluminum oxide insulators, silicon rich oxides with inclusions of nanoparticles of silicon, silicon oxide insulators with inclusions of nanoparticles of silicon carbide, and silicon oxycarbide insulators.
Claim 67
Dependent Claim
20 words
The method of claim 51 , wherein forming the MOSFET includes forming the MOSFET with a composite layer gate insulator.
Claim 68
Dependent Claim
43 words
The method of claim 60 , wherein forming the MOSFET with a composite layer gate insulator includes forming a composite layer gate insulator selected from the group of an oxide-aluminum oxide (Al 2 O 3 )-oxide composite layer, and oxide-silicon oxycarbide-oxide composite layer.
Claim 69
Dependent Claim
45 words
The method of claim 60 , wherein forming the MOSFET with a composite layer gate insulator includes forming a composite layer gate insulator, or a non-stoichiometric single layer, of two or more materials selected from the group of silicon (Si), titanium (Ti), and tantalum (Ta).
Claim 70
Dependent Claim
26 words
The method of claim 51 , wherein forming the MOSFET includes forming the MOSFET such that the gate insulator includes a multiple layer of oxide-nitride-oxide (ONO).
Claim 71
Dependent Claim
34 words
The method of claim 51 , wherein forming the MOSFET includes forming a MOSFET having a storage density of one bit for each 1.0 photolithographic feature squared ( 1 F 2 ) unit area.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2008-02-08 | 2008-08-09 | 2009-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2012-02-08 | 2012-08-09 | 2013-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2016-02-08 | 2016-08-09 | 2017-02-08 | $7700.00 | Window Closed / Lapsed |