Abstract: A semiconductor integrated circuit device includes a cell well, a memory cell array formed on the cell well and having a memory cell area and cell well contact area, first wiring bodies arranged in the memory cell area, and second wiring bodies arranged in the cell well contact area. The layout pattern of the second wiring bodies is the same as the layout pattern of the first wiring bodies. The cell well contact area comprises cell well contacts that have the same dopant type as the cell well and that function as source/drain regions of dummy transistors formed in the cell well contact area.

Abstract: In a nonvolatile semiconductor memory device, a tunnel insulating layer, a charge storage layer and a charge block layer are formed on a silicon substrate in this order, and a plurality of control gate electrodes are provided above the charge block layer. Moreover, a cap layer made of silicon nitride is formed between the charge block layer and each of the control gate electrode, the cap layer being divided for each gate control electrode.

Abstract: A memory device, and method of making the same, in which a trench is formed into the surface of a semiconductor substrate. Source and drain regions define a channel region there between. The drain is formed under the trench. The channel region includes a first portion that extends along a bottom wall of the trench, a second portion that extends along a sidewall of the trench, and a third portion that extends along the surface of the substrate. The floating gate is disposed over the channel region third portion. The control gate is disposed over the floating gate. The select gate is at least partially disposed in the trench and adjacent to the channel region first and second portions. The erase gate disposed adjacent to and insulated from the floating gate.

Abstract: An EEPROM according to the present invention includes: a semiconductor layer of a first conductive type; and a first insulating film formed on the semiconductor layer. A first impurity region, a second impurity region, a third impurity region, a fourth impurity region, and a fifth impurity region of a second conductive type are formed in top layer portions of the semiconductor layer. On the first insulating film, a select gate, a first floating gate, and a second floating gate are respectively disposed opposite a region between the first impurity region and the second impurity region, a region between the second impurity region and the third impurity region, and a region between the third impurity region and the fourth impurity region. In the first insulating film, a first tunnel window and a second tunnel window are respectively formed at portions in contact with the first floating gate and the second floating gate.

Abstract: The leakage current generated due to the extension of the depleted layer to the end of the chip is reduced. In MOSFET 100, the depths of the trenches 112 in the gate pad portion 50 and the circumference portion 70 are larger than the depths of the trenches 111 in the cell region 60. Therefore, the depleted layer extending from the cell region 60 along the direction toward the gate pad portion 50 or the direction toward the circumference portion 70 is blocked by the presence of the trench 112. In other words, an extending of the depleted layer can be terminated by disposing the trench 112, so as to avoid reaching the depleted layer to the end of the semiconductor chip. Accordingly, a leakage current generated from the cell region 60 along the direction toward the end of the semiconductor chip can be reduced.

Abstract: A nonvolatile semiconductor memory device capable of improving injection efficiency and simplifying manufacturing process is provided. The device comprises a memory cell having second conductive type of first impurity diffusion area and second impurity diffusion area on a first conductive type of semiconductor substrate, between the first and second impurity diffusion areas, a first laminate section formed by laminating a first insulating film, a charge storage layer, a second insulating film and a first gate electrode in this order from the bottom, and a second laminate section formed by laminating a third insulating film and a second gate electrode in this order from the bottom, wherein an area sandwiched between the first and second laminate sections is the second conductive type of a third impurity diffusion area having impurity density lower than that of the first and second impurity diffusion areas and not higher than 5×1012 ions/cm2.

Abstract: Nonvolatile flash memory systems and methods are disclosed having a semiconductor substrate of a first conductivity type, including non-diffused channel regions through which electron flow is induced by application of voltage to associated gate elements. A plurality of floating gates are spaced apart from one another and each insulated from the channel region. A plurality of control gates are spaced apart from one another and insulated from the channel region, with each control gate being located between a first floating gate and a second floating gate and capacitively coupled thereto to form a subcell. A plurality of spaced-apart assist gates are insulated from the channel region, with each assist gate being located between and insulated from adjacent subcells. The channel is formed of three regions, two beneath adjacent control gate elements as well as a third region between the first two and beneath an associated assist gate.

Abstract: A stacked body with a plurality of dielectric films and electrode films alternately stacked therein is provided. The electrode film is divided into a plurality of control gate electrodes extending in one direction. The stacked body is provided with a U-pillar penetrating through the select gate electrodes and the control gate electrodes, having one end connected to a source line, and having the other end connected to a bit line. Moreover, a different potential is applied to uppermost one of the control gate electrodes than that applied to the other control gate electrodes.

Abstract: In a method for manufacturing a semiconductor device, an oxide layer, a first polysilicon layer, and a second polysilicon layer are sequentially provided on a substrate. A first hard mask pattern is provided on the second polysilicon layer. The oxide layer, the first polysilicon layer, and the second polysilicon layer are patterned using the first hard mask pattern as a mask to form a lower gate structure including an oxide pattern, a first polysilicon pattern, and a second polysilicon pattern. The lower gate structure is etched to provide an oxidation layer on sidewalls of the lower gate structure. An insulating layer is provided on the lower gate structure including the oxidation layer. The first hard mask pattern is removed to form a first opening in the insulating layer, the first opening exposing the second polysilicon pattern. A metal pattern is formed in the first opening on the second polysilicon pattern, the second polysilicon pattern having the oxidation layer on sidewalls thereof.

Abstract: Non-volatile memory device with polysilicon spacer and method of forming the same. A dielectric layer lines a sidewall of a polysilicon gate. A polysilicon spacer is patterned on the dielectric layer adjacent to the sidewall of the polysilicon gate. A protection spacer is patterned on the dielectric layer and disposed on the polysilicon spacer adjacent to the sidewall of the conductive gate for preventing a shortage path between the polysilicon gate and the polysilicon spacer during a subsequent silicidation process.

Abstract: A semiconductor device with multiple strap-contact configurations for a memory cell array. An array with memory cells interconnected with bit-lines, control-gate lines, erase gate lines, common-source lines, and word-lines is provided. In one aspect of an illustrative embodiment, a strap-contact corridor is spaced at n bit-line intervals (n>1) across the array. The strap-contact corridor comprises strap-contact cells, which provide electrical interconnection between control-gate lines, erase gate lines, common-source lines, and word-lines and their respective straps.

Abstract: A nonvolatile semiconductor memory device includes a plurality of floating gate electrodes respectively formed above a semiconductor substrate with first insulating films disposed therebetween, and a control gate electrode formed above the plurality of floating gate electrodes with a second insulating film disposed therebetween. In each of the plurality of floating gate electrodes is formed to have a width of an upper portion thereof in a channel width direction which is smaller than a width of a lower portion thereof in the channel width direction and one of contact surfaces thereof on at least opposed sides which contact the second insulating film is formed to have one surface, and the second insulating film has a maximum film thickness in a vertical direction, the maximum film thickness being set smaller than a distance from a lowest surface to a highest surface of the second insulating film in the vertical direction.

Abstract: A semiconductor device comprises a first transistor having a composite gate structure containing a lamination of a first polycrystalline silicon film, an interlayer insulating film, and a second polycrystalline silicon film; and a second transistor having a single gate structure containing a lamination of a third polycrystalline silicon film and a fourth polycrystalline silicon film, wherein the first polycrystalline silicon film and the third polycrystalline silicon film have substantially the same thickness; the first polycrystalline silicon film and the third polycrystalline silicon film have different impurity concentrations controlled independently of each other; the second polycrystalline silicon film and the fourth polycrystalline silicon film have substantially the same thickness, and the second polycrystalline silicon film, the fourth polycrystalline silicon film, and the third polycrystalline silicon film have substantially the same impurity concentration.

Abstract: A semiconductor substrate having a main surface, first and second floating gates formed spaced apart from each other on the main surface of the semiconductor substrate, first and second control gates respectively located on the first and second floating gates, a first insulation film formed on the first control gate, a second insulation film formed on the second control gate to contact the first insulation film, and a gap portion formed at least between the first floating gate and the second floating gate by achieving contact between the first insulation film and the second insulation film are included. With this, a function of a nonvolatile semiconductor device can be ensured and a variation in a threshold voltage of a floating gate can be suppressed.

Abstract: A non-volatile memory device comprises a substrate with the dielectric layer formed thereon. A control gate and a floating gate are then formed next to each other on top of the dielectric layer separated by a gap. Accordingly, a non-volatile memory device can be constructed using a single poly process that is compatible with conventional CMOS processes. In addition, assist gates are formed on the dielectric layer next to the control gate and floating gate respectively.

Abstract: A nonvolatile memory device is provided that includes; a first semiconductor layer extending in a first direction, a second semiconductor layer extending in parallel with and separated from the first semiconductor layer, an isolation layer between the first semiconductor layer and second semiconductor layer, a first control gate electrode between the first semiconductor layer and the isolation layer, a second control gate electrode between the second semiconductor layer and the isolation layer, wherein the second control gate electrode and first control gate electrode are respectively disposed at opposite sides of the isolation layer, a first charge storing layer between the first control gate electrode and the first semiconductor layer, and a second charge storing layer between the second control gate electrode and the second semiconductor layer.

Abstract: A method includes the steps of: introducing insulation film into a trench to provide a trench isolation; planarizing the trench isolation to expose a passivation film; and removing the passivation film and depositing a second silicon layer on a first silicon layer and the trench isolation; and in the step of depositing the first silicon layer the first silicon layer is an undoped silicon layer and in the step of depositing the second silicon layer the second silicon layer is a doped silicon layer or an undoped silicon layer subsequently having an impurity introduced thereinto or the like and thermally diffused through subsequent thermal hysteresis into the first silicon layer.

Abstract: In order to reduce the integrated circuit area that is occupied by an array of a given number of flash memory cells, floating gate charge storage elements are positioned along sidewalls of substrate trenches, preferably being formed of doped polysilicon spacers. An array of dual floating gate memory cells includes cells with this structure, as an example. A NAND array of memory cells is another example of an application of this cell structure. The memory cell and array structures have wide application to various specific NOR and NAND memory cell array architectures.

Abstract: There are provided a nonvolatile semiconductor memory of a structure in which electric signals from peripheral circuits are reliably transferred to control gates via word lines even if contact holes cannot be opened accurately above the word lines, and a method of fabricating the nonvolatile semiconductor memory. Plural word lines and plural bit lines are disposed on a semiconductor substrate, and there are memory cells at intersecting portions of the word lines and the bit lines. At contact portions of the word lines and metal wires of an upper layer, polysilicon regions, which include the contact portions, are formed beneath a polysilicon forming the word lines, as an etching stop layer at a time of forming contacts.

Abstract: A flash NAND type EEPROM system with individual ones of an array of charge storage elements, such as floating gates, being capacitively coupled with at least two control gate lines. The control gate lines are preferably positioned between floating gates to be coupled with sidewalls of floating gates. The memory cell coupling ratio is desirably increased, as a result. Both control gate lines on opposite sides of a selected row of floating gates are usually raised to the same voltage while the second control gate lines coupled to unselected rows of floating gates immediately adjacent and on opposite sides of the selected row are kept low. The control gate lines can also be capacitively coupled with the substrate in order to selectively raise its voltage in the region of selected floating gates. The length of the floating gates and the thicknesses of the control gate lines can be made less than the minimum resolution element of the process by forming an etch mask of spacers.

Abstract: In a semiconductor device and a method of forming such a device, the semiconductor device comprises a substrate of semiconductor material extending in a horizontal direction. A plurality of interlayer dielectric layers is provided on the substrate. A plurality of gate patterns is provided, each gate pattern between a neighboring lower interlayer dielectric layer and a neighboring upper interlayer dielectric layer. A vertical channel of semiconductor material extends in a vertical direction through the plurality of interlayer dielectric layers and the plurality of gate patterns, a gate insulating layer between each gate pattern and the vertical channel that insulates the gate pattern from the vertical channel, the vertical channel being in contact with the substrate at a contact region that comprises a semiconducting region.

Abstract: A method for manufacturing a semiconductor device is provided. The method includes forming multiple conductive patterns 13a, forming an intermediate insulating film 16 on all of device isolation insulating films 6 and the conductive patterns 13a, forming a second conductive film 17 on the intermediate insulating film 16, patterning the second conductive film 17, the intermediate insulating film 16, and the multiple conductive patterns 13a, individually, to make the conductive patterns 13a into floating gates 13c and to make the second conductive film 17 into multiple strip-like control gates 17a. In the method, an edge, in a plan layout, of at least one of each of the conductive patterns 13a and each of the device isolation insulating films 6 is bent in a region between the control gates 17a adjacent in a row direction.

Abstract: A nonvolatile semiconductor memory device includes: a semiconductor member; a memory film provided on a surface of the semiconductor member and being capable of storing charge; and a plurality of control gate electrodes provided on the memory film, spaced from each other, and arranged along a direction parallel to the surface. Average dielectric constant of a material interposed between one of the control gate electrodes and a portion of the semiconductor member located immediately below the control gate electrode adjacent to the one control gate electrode is lower than average dielectric constant of a material interposed between the one control gate electrode and a portion of the semiconductor member located immediately below the one control gate electrode.

Abstract: A semiconductor memory in which each memory cell in a NAND flash memory includes a columnar floating gate formed on an element region with a gate insulating film interposed between the floating gate and the element region, diffusion layers formed at portions of the element region located below both sides of the floating gate, and a control gate formed so as to surround the floating gate with an IPD film interposed between the control gate and the floating gate, the IPD film formed on a side surface of the floating gate.

Abstract: A method is provided which includes forming a first gate overlying a major surface of an electronic device substrate and forming a second gate overlying and spaced apart from the first gate. The method further includes forming a charge storage structure horizontally adjacent to, and continuous along, the first gate and the second gate, wherein a major surface of the charge storage structure is substantially vertical to the major surface of the substrate.

Abstract: A semiconductor device including a nonvolatile memory and the fabrication method of the same is described formed on a semiconductor substrate. According to the semiconductor device, a second gate electrode film is used for a gate electrode film of a logic circuit, and for a control gate electrode film of a nonvolatile memory. As the second gate electrode film is formed at a relatively later step in fabrication, subsequent thermal process may be avoided. The gate structure is suitable for miniaturization of the transistor in the logic circuit.

Abstract: A method for forming trenches on a surface of a semiconductor substrate is described. The method may include: etching a first plurality of trenches into the surface of the semiconductor substrate; filling the first plurality of trenches with at least one material; and etching a second plurality of trenches into every second trench of the first plurality of trenches. Furthermore, a method for forming floating-gate electrodes on a semiconductor substrate and an integrated circuit is described.

Abstract: A non-volatile memory cell including a substrate in which is formed a source region and a drain region defining a channel region between the source region and the drain region is provided. The non-volatile memory cell further includes a select gate structure overlying a first portion of the channel region. The non-volatile memory cell further includes a control gate structure formed overlying a second portion of the channel region, wherein the control gate structure includes a nanocrystal stack having a height, wherein the control gate structure has a convex shape in a corner region formed at an intersection of a first plane substantially parallel to a top surface of the substrate and a second plane substantially parallel to a side surface of the control gate structure, wherein a ratio of radius of the control gate structure in the corner region to the height of the nanocrystal stack is at least 0.5.

Abstract: Non-volatile memory devices and methods for fabricating non-volatile memory devices are disclosed. More specifically, split gate memory devices are provided having frameworks that provide increased floating gate coupling ratios, thereby enabling enhanced programming and erasing efficiency and performance.

Abstract: A micro electronic component, preferably in the form of an electronic memory, includes the use of clusters as an electronic memory. Also disclosed as part of the present invention is a method for fabricating a micro electronic component. The present invention contemplates fabrication of an especially compact electronic memory that works especially with single-electron transistors or single-electronic transfers. According to the present invention, clusters with a metallic cluster nucleus are arranged in parallel grooves essentially in lines or rows and are connected individually to first and second connecting electrodes, such that individually the clusters can be electrically modified or polled independently of each other.

Abstract: A neuron device includes: a semiconductor layer; source and drain regions formed in the semiconductor layer at a distance from each other; a protection film formed on an upper face of the semiconductor layer; a channel region formed in the semiconductor layer between the source region and the drain region; a pair of gate insulating films formed on two side faces of the channel region; a floating gate electrode including: a first portion covered on the gate insulating films and the protection film; a second portion connected to the first portion; and a third portion provided on the substrate so as to connect to the end portion of the second portion on the opposite side from the first portion; an interelectrode insulating film provided on the first to third portions; and a plurality of control gate electrodes provided on the third portion.

Abstract: The present invention provides a high-performance MONOS-type NAND-type nonvolatile semiconductor memory device using an aluminum oxide film as a part of gate insulating film in a select transistor and as a block insulating film in a memory transistor. The NAND-type nonvolatile semiconductor memory device has, on a semiconductor substrate, a plurality of memory cell transistors connected to each other in series and a select transistor. The memory cell transistor includes a first insulating film on the semiconductor substrate, a charge trapping layer, a second insulating film made of aluminum oxide, a first control gate electrode, and a first source/drain region. The select transistor includes a third insulating film on the semiconductor substrate, a fourth insulating film made of an aluminum oxide containing at least one of a tetravalent cationic element, a pentavalent cationic element, and N (nitrogen), a second control gate electrode, and a second source/drain region.

Abstract: A flash memory cell is disclosed in the specification and drawing. The flash memory cell is described and shown with at least one floating gate heavily doped with P-type ions.

Abstract: Memory arrays and methods of forming memory arrays are disclosed. One such memory array has a first string of serially-coupled first memory cells and a second string of serially-coupled second memory cells sharing a single conductive pillar which forms a channel for both strings of serially-coupled memory cells. For example, a first memory cell can have a first control gate on the first side of the conductive pillar and a first charge trap interposed between the first side of the conductive pillar and the first control gate. A second memory cell can have a second control gate on the second side of the conductive pillar and a second charge trap interposed between the second side of the conductive pillar and the second control gate. The first and second charge traps are electrically isolated from each other and the first and second control gates can be electrically isolated from each other.

Abstract: A FLASH memory device is provided including a plurality of first floating gates formed over a gate oxide layer formed over a substrate, the first group of floating gates being formed using a selected photolithography process associated with a minimum line width; a second group of floating gates including a plurality of second floating gates, wherein the first and second floating gates are disposed in series, with individual ones of the second floating gates disposed between respective ones of the first floating gates; a plurality of spacers, individual ones of the spacers disposed between adjacent ones of the first and second floating gates; a plurality of control gates associated with the floating gates, wherein the spacers and/or the second floating gates have widths less than the minimum line width.

Abstract: A method of fabricating a non-volatile memory device according to example embodiments may include forming a semiconductor layer on a substrate. A plurality of lower charge storing layers may be formed on a bottom surface of the semiconductor layer. A plurality of lower control gate electrodes may be formed on the plurality of lower charge storing layers. A plurality of upper charge storing layers may be formed on a top surface of the semiconductor layer. A plurality of upper control gate electrodes may be formed on the plurality of upper charge storing layers, wherein the plurality of lower and upper control gate electrodes may be arranged alternately.

Abstract: An EEPROM flash memory device having a floating gate electrode enabling a reduced erase voltage and method for forming the same, the floating gate electrode including an outer edge portion including multiple charge transfer pointed tips.

Abstract: A non-volatile memory device includes a semiconductor substrate, first and second control gates, and first and second charge storage patterns. The semiconductor substrate includes a protruding active pin having a source region, a drain region and a channel region located between the source and drain regions. The first control gate is located on a first sidewall of the channel region, and the second control gate is located on a second sidewall of the channel region. The second control gate is separated from the first control gate. The first charge storage pattern is located between the first sidewall and the first control gate, and the second charge storage pattern is located between the second sidewall and the second control gate.

Abstract: Disclosure is semiconductor device of a selective gate region, comprising a semiconductor layer, a first insulating film formed on the semiconductor layer, a first electrode layer formed on the first insulating layer, an element isolating region comprising an element isolating insulating film formed to extend through the first electrode layer and the first insulating film to reach an inner region of the semiconductor layer, the element isolating region isolating a element region and being self-aligned with the first electrode layer, a second insulating film formed on the first electrode layer and the element isolating region, an open portion exposing a surface of the first electrode layer being formed in the second insulating film, and a second electrode layer formed on the second insulating film and the exposed surface of the first electrode layer, the second electrode layer being electronically connected to the first electrode layer via the open portion.

Abstract: One embodiment of the invention comprises a first semiconductor structure in electrical contact with a first contact region, a second semiconductor structure in electrical contact with a second contact region, the first semiconductor structure and the second semiconductor structure being in electrical contact with each-other along an interface, a modulating section configured to modulate the conductivity in at least one of the semiconductor structures, so that the conductivity varies along the interface, in such a way that if current flows across the interface, the current can flow only at a predetermined position along the interface, and substantially no current can flow at either side of the predetermined position.

Abstract: Non-volatile semiconductor memory devices with dual control gate memory cells and methods of forming are provided. A charge storage layer is etched into strips extending across a substrate surface in a row direction with a tunnel dielectric layer therebetween. The resulting strips may be continuous in the row direction or may comprise individual charge storage regions if already divided along their length in the row direction. A second layer of dielectric material is formed along the sidewalls of the strips and over the tunnel dielectric layer in the spaces therebetween. The second layer is etched into regions overlaying the tunnel dielectric layer in the spaces between strips. An intermediate dielectric layer is formed along exposed portions of the sidewalls of the strips and over the second dielectric layer in the spaces therebetween. A layer of control gate material is deposited in the spaces between strips.

Abstract: Provided are a non-volatile memory device that may expand to a stacked structure and may be more easily highly integrated and an economical method of fabricating the non-volatile memory device. The non-volatile memory device may include at least one semiconductor column. At least one first control gate electrode may be arranged on a first side of the at least one semiconductor column. At least one second control gate electrode may be arranged on a second side of the at least one semiconductor column. A first charge storage layer may be between the at least one first control gate electrode and the at least one semiconductor column. A second charge storage layer may be between the at least one second control gate electrode and the at least one semiconductor column.

Abstract: A semiconductor device includes: a first FET that is formed with first unit FETs each having a first finger electrode and a second finger electrode provided on either side of a gate finger electrode, the first unit FETs being connected in parallel; and a second FET that is formed with second unit FETs each having a first finger electrode and a second finger electrode provided on either side of a gate finger electrode, the second unit FETs being connected in parallel. In this semiconductor device, the second finger electrode of each of the first unit FETs and the first finger electrode of each corresponding one of the second unit FETs form a common finger electrode, and the first finger electrodes of the first unit FETs, the second finger electrodes of the second unit FETs, and the common finger electrodes are arranged in the gate length direction of the first FET and the second FET.

Abstract: A flash memory device includes control gates that are formed to completely surround the top and sides of floating gates. The control gates are located between the floating gates that are adjacent in the word line direction as well as the floating gates that are adjacent in the bit line direction. The present flash memory device reduces a shift in a threshold voltage resulting from interference among floating gates and increases an overlapping area of the floating gate and the control gates. Thus, there is an effect in that the coupling ratio can be increased.

Abstract: A nonvolatile semiconductor memory device includes a semiconductor substrate, a select gate formed above the semiconductor substrate, a floating gate formed above the semiconductor substrate and an erase gate positioned lower than an upper surface of the floating gate, and opposite an edge of a lower surface of the floating gate.

Abstract: A memory device is disclosed. A floating gate is disposed overlying a substrate. A tunneling dielectric layer is interposed between the floating gate and the substrate. An inter poly dielectric layer is disposed overlying the floating gate and the substrate. A word line is disposed overlying the floating gate, extending in a row direction. A bit line is disposed in the substrate, extending in a column direction, wherein the bit line is partially overlapped by the floating gate and the word line.

Abstract: A two-transistor non-volatile memory cell is formed in a semiconductor body. A memory-transistor well is disposed within the semiconductor body. A switch-transistor well is disposed within the semiconductor body and is electrically isolated from the memory transistor well. A memory transistor including spaced-apart source and drain regions is formed within the memory-transistor well. A switch transistor including spaced-apart source and drain regions is formed within the switch-transistor well region. A floating gate is insulated from and self aligned with the source and drain regions of the memory transistor and switch transistor. A control gate is disposed above and aligned to the floating gate and with the source and drain regions of the memory transistor and the switch transistor.

Abstract: A NAND non-volatile two-bit memory cell comprises a cell stack and two select stacks disposed on an active area of a substrate. Each select stack is respectively disposed on a side of the cell stack with a sidewall between the cell stack and a respective select stack. The cell stack has four components: a first dielectric layer disposed over the substrate; a charge accumulation layer capable of holding charge in a portion thereof to store information and disposed over the first dielectric layer; a second dielectric layer disposed over the charge accumulation layer; and a control gate disposed over the second dielectric layer. The select stack has two components: a third dielectric layer disposed over the substrate and a select gate, capable of inverting an underneath channel region to function as a source or a drain of the memory cell, disposed over the third dielectric layer.

Abstract: A non-volatile memory including one or more EEPROM cell pairs. Each EEPROM cell pair includes three transistors and stores two data bits, effectively providing a 1.5 transistor EEPROM cell. An EEPROM cell pair includes a first non-volatile memory transistor, a second non-volatile memory transistor and a source access transistor. The source access transistor includes: a first source region continuous with a source region of the first non-volatile memory transistor; a second source region continuous with a source region of the second non-volatile memory transistor, and a drain region that extends downward through a first well region to contact a second well region. The first, second and third semiconductor regions and the second well region have a first conductivity type, and the first well region has a second conductivity type, opposite the first conductivity type.

Abstract: A non-volatile memory is provided. An assist gate structure is formed on a substrate such that the width at the bottom of the assist gate structure is greater than the width at the top of the assist gate structure. A floating gate is formed on one side of the assist gate structure and disposed between a word line and the substrate. The width at the bottom of the floating gate is smaller than the width at the top of the floating gate. The word line, the floating gate and the assist gate structure together form a memory unit. A tunneling dielectric layer is formed between the floating gate and the substrate. An inter-gate dielectric layer is formed between the word line, the floating gate and the assist gate structure. Source/drain regions are formed in the substrate on the respective sides of the memory unit.