Abstract: A fully recessed device structure and method for low power applications comprises a trenched floating gate and a trenched control gate formed in a single trench etched into a well junction region in a semiconductor substrate to provide a substantially planar topography for low power applications. The trenched floating gate is electrically isolated from the trenched control gate by an inter-gate dielectric layer formed inside the trench and on a top surface of the trenched floating gate. The trenched control gate is formed on a top surface of the inter-gate dielectric layer and preferably, has a top surface which is substantially planar with a top surface of the semiconductor substrate. The fully recessed structure further comprises a buried source region, a buried drain region and a channel region. The buried source region and the buried drain region are formed in the well junction region and are laterally separated by the trench.

Abstract: A non-volatile memory cell and a manufacturing process therefor are discussed. The cell is integrated in a semiconductor substrate and includes a floating gate transistor having a first source region, first drain region, and gate region projecting over the substrate between the first source and drain regions. The cell also includes a selection transistor having a second source region, second drain region, and respective gate region, projecting over the substrate between the second source and drain regions. The first and second regions are lightly doped and the cell comprises mask elements.

Abstract: A method for fabricating a single polysilicon, non-volatile memory device, has been developed. The method features the use of a metal structure, comprised to contact an underlying control gate region, located in the semiconductor structure, in addition to providing the upper electrode, for a capacitor structure. The capacitor structure, in addition to the metal structure used as the upper electrode, is also comprised of an underlying capacitor dielectric layer, and an underlying polysilicon floating gate structure, used as the lower electrode of the capacitor structure. The creation of the capacitor structure results in performance increases realized via the additional control gate coupling capacitance, obtained via the novel configuration described in this invention.

Abstract: A memory cell array of a nonvolatile semiconductor memory device is provided with a bipolar transistor whose base is connected to a node between sources of two memory cell transistors. A memory cell SL decoder controls the potential level of an emitter of the bipolar transistor. A collector of the bipolar transistor is held at a ground potential. In a read operation, the emitter potential is so controlled that the bipolar transistor enters an ON state, and a current flowing through a channel of either memory cell transistor is amplified by the bipolar transistor to be read.

Abstract: This invention relates to the new reversed flash memory device which has improved electrical performance, yield and reliability because of better control of the dielectric interfaces resulting from first making the poly 2 control gate within the silicon substrate. The reverse structure is novel, as are the described process methods for forming the reverse stacking order.Shallow trenched isolation (STI) is first formed in the p-silicon substrate and encompasses the poly 2 control gate region; then the interpoly dielectric is grown/deposited on that single crystal silicon substrate. The floating poly 1 is formed on top of this uniform interpoly dielectric that has well-controlled surface smoothness. The tunnel oxide layer is formed on the floating poly 1 layer, and the source/drain is implanted on a straddling additional poly layer. There are fewer edges and associated stress weaknesses in the dielectric breakdown of both the reversed interpoly dielectric and the floating tunnel oxide.

Abstract: An improved EEPROM cell having a field-edgeless tunnel window is provided which is fabricated by a STI process so as to produce reliable endurance and data retention. The EEPROM cell includes a floating gate, a programmable junction region, and a tunneling oxide layer separating the programmable junction region and the floating gate. The tunneling oxide layer defines a tunnel window which allows for programming and erasing of the floating gate by tunneling electrons therethrough. The programmable junction region has a width dimension and a length dimension so as to define a first area. The tunnel window has a width dimension and a length dimension so as to define a second area. The second area of the tunnel window is completely confined within the first area of the programmable junction region so as to form a field-edgeless tunnel window.

Abstract: An improved integrated electrically adjustable analog transistor device is delineated wherein the device has multiple sub-structures to optimize performance of the device. One of the sub-structures is particularly well suited for charging the device's insulated gate. Additional sub-structures, each different in dimensions and electrical characteristics from the first sub-structure, are implemented for optimal use with an external electrical circuit.

Abstract: A semiconductor integrated circuit comprises a substrate including a plurality of transistors, and a conductive line for coupling at least two of the transistors with each other, each transistor comprising a drain diffusion region, a source diffusion region, a gate region, and a test diffusion region within the substrate, the test diffusion region being electrically coupled to a metal line within the semiconductor integrated circuit for establishing an indication of the voltage at the probing diffusion region.

Abstract: A non-volatile memory cell includes a well region formed in a semiconductor substrate. First and second avalanche injection elements reside in the well region. A bifurcated floating-gate electrode includes a first segment overlying the first avalanche injection element and a second segment overlying the second avalanche injection element. A first contact region resides in the well region adjacent to the first segment of the floating-gate electrode, and a second contact region resides in the well region adjacent to the second segment of the floating-gate electrode. Upon the application of programming or erasing voltage, electrical charge is independently transferred to each of the first and second segments of the floating-gate electrode from the first and second avalanche injection elements, respectively.

Abstract: A floating gate transistor has a reduced barrier energy at an interface between a gallium nitride (GaN) or gallium aluminum nitride (GaAlN) floating gate an adjacent gate insulator, allowing faster charge transfer across the gate insulator at lower voltages. Data is stored as charge on the floating gate. The data charge retention time on the floating gate is reduced. The data stored on the floating gate is dynamically refreshed. The floating gate transistor provides a dense and planar dynamic electrically alterable and programmable read only memory (DEAPROM) cell adapted for uses such as for a dynamic random access memory (DRAM) or a dynamically refreshed flash EEPROM memory. The floating gate transistor provides a high gain memory cell and low voltage operation.

Abstract: A zero-power non-volatile memory cell includes a control element, an avalanche injection element, and a CMOS inverter. A floating-gate electrode is capacitively coupled to the control element, the avalanche injection element, and to the CMOS inverter. The avalanche injection element is arranged, so as to transfer electrical charge onto the floating-gate electrode. The presence of stored data within the memory cell is indicated by reading a supply voltage V.sub.DD at an output terminal of the inverter. Accordingly, data can be read from the non-volatile memory cell without applying electrical power to the cell.

Abstract: A nonvolatile memory device includes a floating-gate electrode (14) overlying a surface (24) of a substrate (10). A diffusion barrier layer (34) extends from the substrate surface (24) along a wall surface (30) of the floating-gate electrode (14) to an upper surface (32) of the floating-gate electrode (14) and overlies the upper surface (32). The diffusion barrier layer (34) blocks the silicidation of the floating-gate electrode (14) and prevents ionic contaminants from diffusing to the floating-gate electrode (14). A charge control region (42) of the floating-gate electrode (14) is capacitively coupled to a well region (40) within the substrate (10). The well region (40) functions as a diffused control-gate electrode and regulates the voltage of the floating-gate electrode (14).

Abstract: A FLASH EPROM layout with straight gate and isolation structures to improve scalability and eliminate the need for self-aligned source process.

Abstract: Hot-electron injection driven by a hole impact ionization mechanism at the channel-drain junction provides a new method of hot electron injection. Using this mechanism, a four-terminal pFET floating-gate silicon MOS transistor for analog learning applications provides nonvolatile memory storage. Electron tunneling permits bidirectional memory updates. Because these updates depend on both the stored memory value and the transistor terminal voltages, the synapses can implement a learning function. The synapse learning follows a simple power law. Unlike conventional EEPROMs, the synapses allow simultaneous memory reading and writing. Synapse transistor arrays can therefore compute both the array output, and local memory updates, in parallel. Synaptic arrays employing these devices enjoy write and erase isolation between array synapses is better than 0.01% because the tunneling and injection processes are exponential in the transistor terminal voltages.

Abstract: A method of providing oxide layers at the surface of the semiconductor substrate suitable for use with the formation of programmable logic devices. The method comprises the steps of: depositing a layer of nitride on the surface of the semiconductor substrate; etching a first and second portions of the nitride layer; forming a first and second regions of a first oxide layer on the substrate in the first and second etched portions of the nitride layer; etching a the first region of the oxide; forming a second oxide layer on the substrate having a first portion in the first etched portion of the nitride and a second portion overlying the first portion of the second region of the first oxide layer; removing the nitride layer; and forming a third layer of oxide having a first portion on the surface of the substrate, a second and third portions on the first and second portions of the second oxide layer.

Abstract: A semiconductor device comprises a semiconductor substrate, and a plurality of semiconductor elements provided on the semiconductor substrate. Each of the semiconductor elements includes a gate dielectric film formed on the semiconductor substrate, a gate electrode formed on the semiconductor substrate with the gate dielectric film interposed therebetween, and having a pair of side surfaces, and source/drain regions formed in a surface of the semiconductor substrate along the pair of the side surfaces. The gate electrode contains a plurality of crystal grains, and the number of the crystal grains is substantially equal to the number of crystal grains contained in any other gate electrode of all the semiconductor elements.

Abstract: An integrated circuit ("IC") having three different oxide layer thicknesses and a process for manufacturing the IC using a single oxide growth step is provided. A first region is formed on a substrate surface with oxidation enhancing properties. A second region is formed on the substrate surface with a dose of nitrogen that retards oxidation. An oxide layer is grown from the first and the second regions and a third region of the substrate such that the first, second, and third regions yield a first oxide layer for the capacitor, a second oxide layer for the read transistor and a third oxide layer for the write transistor.

Abstract: A flash EEPROM memory cell comprises source and drain regions defining a channel region therebetween, a floating gate and a control gate. The source and drain regions are first and second doped semiconductor regions of a first conductivity type formed in a first active area region of a semiconductor material layer of a second conductivity type; the control gate comprises a third doped semiconductor region of the first conductivity type formed in a second active area region of the semiconductor material layer; and the floating gate comprises a polysilicon strip insulatively disposed over the channel region and insulatively extending over the third doped semiconductor region.

Abstract: A two-device nonvolatile memory cell is described. The cell comprises a planar FET and a vertical FET in series. The vertical FET has a floating gate that is predominantly capacitively coupled to a buried n well that serves as the control electrode. The structure is very similar to a trench DRAM cell, and the nonvolatile memory cell can be integrated onto a DRAM chip.

Abstract: A tunnel region is surrounded by an impurity diffusion layer and a drain diffusion layer, and a coupling portion coupling one and the other end portions of a floating gate to each other is arranged on only an isolation region. With this arrangement, even if a parasitic inversion layer is formed below the other end portion upon extraction of electrons, the parasitic inversion layer does not contact a semiconductor substrate, resulting in a small substrate current. Therefore, a high-voltage, large-current external power supply need not be prepared in addition to a normal voltage power supply.

Abstract: A MOSFET device with a substrate covered with dielectric material with the device including a plurality of buried conductors capacitively coupled to a polysilicon electrode, made by the steps comprisingforming between regions containing MOSFET devices a region with a plurality of bit lines in the substrate by ion implantation through the gate oxide into the substrate in a predetermined pattern and,forming a polysilicon electrode on the dielectric material crossing over the bit lines.

Abstract: An electrically erasable programmable read-only memory CEEPROM) includes a field effect transistor and a control gate spaced apart on a first insulating layer, a second insulating layer formed over the field effect transistor and the control gate and a common floating gate on the second insulating layer over the channel of the field effect transistor and the control gate, the floating gate thus also forms the gate electrode of the field-effect transistor. The EEPROM devices may be interconnected in a memory array and a plurality of memory arrays may be stacked on upon another. The invention overcomes the problem of using a non-standard silicon-on-insulator (SOI) CMOS process to make EEPROM arrays with high areal density.

Abstract: A flash E.sup.2 PROM cell includes a single polysilicon layer part of which makes up the floating gate of a transistor of the cell, part of which makes up an electrode of a capacitor coupled to the floating gate, and part of which makes up the gate of a second transistor of the cell.

Abstract: A densely packed array of vertical semiconductor devices and methods of making thereof are disclosed. The array has columns of bitlines and rows of wordlines. The gates of the transistors act as the wordlines, while the source or drain regions acts as the bitlines. The array also has vertical pillars, acting as a channel, formed between source and drain regions. The source regions are self-aligned and located below the pillars. The source regions of adjacent bitlines are isolated from each other without increasing the cell size and allowing a minimum area of approximately 4F.sup.2 to be maintained. The isolated sources allow individual cells to be addressed and written via direct tunneling, in both volatile and non-volatile memory cell configurations. The source may be initially implanted. Alternatively, the source may be diffused below the pillars after forming thereof.

Abstract: An electrically-erasable programmable read-only memory (EEPROM) cell includes a split-gate read transistor and a buried N-plate control gate. The split gate transistor includes a drain and source regions formed in a P-type silicon substrate with a channel formed therebetween. Silicon dioxide is disposed over the drain, channel and source regions wherein the oxide overlying the drain and a portion of the channel is thicker compared to the thickness of the oxide overlying the remainder of the channel and the source. A layer of polycrystalline silicon is disposed over the channel. The buried N-plate control gate is spaced laterally from the source, drain, and channel regions. The floating gate overlying the channel extends also over the buried N-plate control gate. The split gate structure effectively realizes a pair of in-series gates, each having a different threshold voltage in accordance with the thickness of the oxide used.

Abstract: A select MOS transistor and a data storage MOS transistor are formed in an element region. The transistor has floating-gate electrodes. The floating-gate electrodes are spaced apart above the element region and connected to each other above a field region. Only a tunnel insulating film much thinner than a gate insulating film of the transistor is placed between the floating-gate electrode and a drain region. Only the gate insulating film much thinner than the gate insulating film of the transistor is placed between the floating-gate electrode and the channel region of the transistor. In the element region, the shape of a control electrode is the same as that of the floating-gate electrodes.

Abstract: A P-channel single-poly EPROM cell has P+ source and P+ drain regions, and a channel extending therebetween, formed in an N-type well. A thin layer of tunnel oxide is provided over the channel and, in some embodiments, over significant portions of P+ source and P+ drain regions. A poly-silicon floating gate overlies the tunnel oxide. A P diffusion region is formed in a portion of the N-well underlying the floating gate and is thereby capacitively coupled to the floating gate. In this manner, the P diffusion region serves as a control gate for the memory cell. Programming is accomplished by coupling a sufficient voltage to the floating gate via the control gate while biasing the source and drain regions to cause the hot injection of electrons from the N-well/drain junction to the floating gate, while erasing is realized by biasing the floating gate, N-well, source and drain regions appropriately so as cause the tunneling of electrons from the floating gate to the N-well, the source, and the drain.

Abstract: The provision of an isolation gate connecting unassociated active areas of adjacent transistors formed in a semiconductor substrate provides effective isolation of the adjacent transistors with no additional process steps required. The isolation gate is tied to a reference to ensure that a channel between the unassociated active areas is not formed, and effective isolation is provided. The adjacent transistors are cross coupled to form sense amplifiers for dynamic random access memory devices.

Abstract: A raised-bitline, contactless flash memory device with trenches on a semiconductor substrate doped with a first conductivity type includes a first well of an opposite conductivity type comprising a deep conductor line to a device, and a second well of the first conductivity type above the first well comprising a body line to the device. Deep trenches extend through the second well into the first well. The trenches are filled with a first dielectric. There are gate electrode stacks for a flash memory device including a gate oxide layer over the device. First doped polysilicon floating gates are formed over the gate oxide layer. An interpolysilicon dielectric layer is formed over floating gate electrodes, and control gate electrodes formed of doped polysilicon layer overlie the interpolysilicon dielectric layer. A dielectric cap overlies the control gate electrodes.

Abstract: A floating gate diode which can be used as a sourceless memory cell, and which may be arranged into an array of memory cells is disclosed. The floating gate diode comprises: a drain region formed in a substrate; an oxide overlying and associated with the drain region; and a floating gate overlying the oxide. Upon application of a voltage to the drain, a current between the drain and substrate is induced in proportion to an amount of electrons stored on the gate. The cells may be arranged into an array which comprises a substrate having a surface; a plurality of drain regions, one of said drain regions respectively corresponding to one of the plurality of cells, formed in the substrate; an oxide region overlying the plurality of drain regions on the surface of the substrate; and a plurality of floating gates overlying the oxide and respectively associated with the plurality of drain regions.

Abstract: This invention discloses a programmable read-only-memory (PROM). The PROM is formed and supported on a substrate. The PROM includes a transistor region in the substrate including a source region, a drain region and a floating gate region disposed between the drain region and the source region. The PROM further includes a floating gate formed on top of the floating gate region with a single poly layer on the substrate. The PROM further includes a floating gate extension region disposed near the transistor region, the floating gate extension region is connected with the floating gate region. The PROM further includes a control gate formed on the substrate near the floating gate extension region opposite the transistor region whereby a charge state of the floating gate extension region is controlled by the control gate.

Abstract: An N well and an n-type ground wiring layer are formed in a P-substrate by diffusion. A word line consisting of p-type polysilicon is formed in the N well. The drain and source regions of a memory cell transistor are formed near the N well by ion-implanting arsenic into the P-substrate. A continuous floating gate is formed on the channel region between the drain and source regions and the word line region through a predetermined gap. The p-type silicon portion opposing this floating gate serves as the control gate of the memory cell transistor. When a pulse alternately and repeatedly having potentials of +3 V and -10 V is applied to the word line, the thresholds of the corresponding memory cell transistors converge to a value corresponding to +3 V of the pulse.

Abstract: An electrically erasable and programmable read only memory device includes a plurality of memory cells, each of which has a drain region, a source region, and a programming region, a first gate insulating film covering a part of the drain region, a second gate insulating film covering a part of the programming region, and a floating gate having a first portion overlapping the first gate insulating film to form a first capacitance therebetween and a second portion overlapping the second gate insulating film to form a second capacitance. The first capacitance is designed to be larger than the second capacitance, so that the injection and extraction of carriers take place between the programming region and the floating gate.

Abstract: A compact contactless flash memory array for semiconductor EEPROM devices having a number of memory cell units. Field oxide layers for the flash memory array are first grown over the surface of an SOI wafer. Gate oxide layers are then grown. Floating gates are then formed by patterning the first polysilicon layer. Source/drain buried bitlines for the flash memory array are formed. A first BPSG (borophosphosilicate glass) layer is deposited and then reflown and etched back. An oxide-nitride-oxide layer is formed. A second polysilicon layer is deposited with in-situ dope. A WSi.sub.x layer then forms. Stacked gates for the flash array are formed by patterning into the formed oxide-nitride-oxide, second polysilicon and WSi.sub.x layers. The stacked gates are then covered with a second BPSG layer. Contact openings for the source/drain buried lines are formed.

Abstract: A compact contactless trenched flash memory array for semiconductor EEPROM devices is disclosed. The flash memory array comprises a number of memory cell units. Each of the cell units comprises a body line, source and drain regions and a stacked gate constructed over a silicon wafer substrate. The source and drain regions are buried regions and the body line is isolated by the surrounding buried source/drain regions and trenches formed to cut deep down to the substrate of the wafer. The stacked gate includes a first polysilicon layer, an oxide-nitride-oxide configuration, a second polysilicon layer, a pad oxide layer and a nitride layer. The source and drain buried regions sandwiches the body line, and the stacked gate substantially sits directly atop the body line. The flash memory array is free from the serious problem of short channel effect.

Abstract: An EEPROM with separated floating gate to reduce the antenna ratio is disclosed. The structure of the EEPROM includes field oxides formed on a wafer. A control gate is formed in the wafer. A first gate oxide formed above the wafer for isolation. A first polysilicon portion is formed on the first gate oxide, which includes a gate for a transistor, a first contact window and a floating gate. Further, the floating gate is set above the control gate. A second gate oxide is formed on the wafer adjacent to the field oxide for isolation. A tunneling window is formed in the second gate oxide. A second polysilicon portion having a second contact window is formed on the second gate oxide. A dielectric layer is formed on the first polysilicon portion and the second polysilicon portion. Contact holes are formed in the dielectric layer and a connecting structure formed in the contact holes and on the dielectric layer for interconnection.

Abstract: Each of source regions (4) is provided only immediately below a bottom surface (3B) of each of trenches (3) which is formed in a silicon substrate (1), extending inward from a main surface (1S) thereof along a second direction, and each of gate electrode portions (23) is provided inside each of the trenches (3). Specifically, each of the gate electrode portions (23) consists of a gate oxide film (19) formed on a side surface (S1) and part of the bottom surface (3B) of the trench (3), an FG electrode (20) formed thereon, a gate insulating film (21) formed on a side surface of the FG electrode (20) which is out of contact with the gate oxide film (19), an upper surface of the FG electrode (20), a side surface (2S) and the other part of the bottom (3B) of the trench (3), and a CG electrode (22) formed so as to cover an upper surface of the gate insulating film (21). Each of drain regions (11) is shared by the two adjacent transistors.

Abstract: A non-volatile semiconductor memory device including a memory cell having a memory transistor and a selection transistor, comprising: a composite gate structure of the memory transistor formed on a surface of a semiconductor substrate at its first region with a first insulating film interposed therebetween and including a laminate of a floating gate electrode, a second insulating film and a control gate electrode; a gate electrode of the selection transistor formed on the surface of the semiconductor substrate at its second region close to the first region with a third insulating film interposed therebetween; and an impurity diffusion layer formed in the semiconductor substrate at its region between the first and second regions and functioning as a drain of the memory transistor, common to a source of the selection transistor, the impurity diffusion layer having at least an extension region extending to a part of the semiconductor substrate disposed under the composite gate structure, the extension region hav

Abstract: The presently preferred embodiment of the invention provides a memory structure that eliminates the thick gate associated with the offset of the FAMOS transistor and reduces the standard 225 angstrom offset to a 100 angstrom offset required for FN tunnelling. The 100 angstrom offset is realized uniformly underneath the entire area of the floating poly. The invention uses transistors each having a 100 angstrom offset to realize both erase and programming functions. The present invention realizes an erasing feature through an erase transistor and an ERL line. However, the programming of the cell will be realized through the programming transistor. As a result, a double poly flash cell will function like an EEPROM. This functioning eliminates the hot electron tunnelling required to program conventional double poly flash cells and results in a significant reduction in chip real estate. The reduction allows the present invention to be scaled to next generation architectures.

Abstract: A nonvolatile memory cell (10) includes a single n-channel insulated gate FET (11) having a single floating gate (12). The FET (11) operates asymmetrically in a sense that the capacitance of a parasitic gate-source capacitor (24) is smaller than the capacitance of a parasitic gate-drain capacitor (26). The asymmetric condition is achievable either by fabricating the FET (11) as an asymmetric structure (30, 60) or by adjusting the capacitance of the parasitic capacitors (24, 26) through terminal biasing when the FET (11) is a short channel device. The potential of the floating gate (12) is controlled by biasing the source (14), drain (16), and substrate (18) of the FET (11). The cell (10) is programmed by moving charge onto the floating gate (12) via hot carrier injection, erased by moving charge from the floating gate (12) via tunneling, and read by sensing the conductive state of the FET (11).

Abstract: A layered bismuth ferroelectric structure (12) and a method for forming the bismuth layered ferroelectric structure (12). A monolayer (12A) of bismuth is formed in intimate contact with a single crystalline semiconductor material (11). A layered ferroelectric material (12) is grown on the monolayer (12A) of bismuth such that the monolayer (12A) of bismuth becomes a part of the layered ferroelectric material (12). The ferroelectric material (12) forms a layered ferroelectric material which is not a pure perovskite, wherein the crystalline structure at the interface between the single crystalline semiconductor material (11) and the monolayer (12A) of bismuth are substantially the same.

Abstract: A nonvolatile storage element of single-layer gate structure constructed by arranging a floating gate formed of a conductive layer to partly overlap with a control gate formed of a diffused layer is provided with a barrier layer covering a part or the whole of the surface of the floating gate. Such nonvolatile storage elements are used for redundancy control of defects or change of functions.

Abstract: A fast, fieldless flash memory cell includes an erase node having a control gate and a floating gate, both formed of polycrystalline silicon, a program transistor sharing the floating gate and control gate with the erase node, and a read transistor sharing the floating gate and control gate with the erase node and program transistor. The inventive memory cell is suitable for use in fast Programmable Logic Devices (PLDs) in the sub 5 nS range (2-5 nS), and other logic and memory parts.

Abstract: A P-channel single-poly non-volatile memory cell having P+ source and P+ drain regions and a channel extending therebetween is formed in an N-type well. An overlying poly-silicon floating gate is separated from the N-well by a thin oxide layer. A P-type diffusion region is formed in a portion of the N-well underlying the floating gate and is thereby capacitively coupled to the floating gate. Within this P-type diffusion area lies an N-type diffusion area which serves as the control gate for the cell. The P-type diffusion region electrically isolates the control gate from the N-well such that voltages may be applied to the control gate in excess of those applied to the N-well without creating a current path from the control gate to the N-well. Programming is accomplished by coupling a sufficient voltage to the floating gate via the control gate while biasing the source and drain regions so as to cause the tunneling of electrons from the P+ drain region of the cell to the floating gate.

Abstract: An integrated circuit memory cell (10) is formed with a P-N junction polycrystalline floating gate (13) with a lightly boron doped on the source side (13B) and a heavily arsenic or phosphorous doped on the drain side (13A) plus the channel region (Ch) . The cells (10) are formed in an array at a face of a semiconductor body (22), each cell including a source (11) and including a drain (12). An improved over-erase characteristic is achieved by forming a P-N junction (JU) in the floating gate (13). Use of a P-N junction (JU) in polycrystalline floating gate (13) prevents the cell (10) from going into depletion, causes a tighter distribution of erased threshold voltages V.sub.T, and improves device life because fewer electrons travel through the gate oxide (30).

Abstract: A single-poly neuron transistor is formed by utilizing a series of doped substrate regions in lieu of the input gates that are conventionally used to form neuron transistors. With conventional neuron transistors, the input gates are isolated from the floating gate by a layer of interpoly dielectric. In the present invention, the series of doped substrate regions are isolated from the floating gate by a layer of gate oxide.

Abstract: A non-volatile memory device in which gate electrodes are formed on an upper surface and a lower surface of the channel via insulating layers, respectively, one of them is used as a read electrode and the other is used as a write electrode, whereby, at a read operation the reading is carried out without exerting an influence upon stored charges stored at the time of writing. Particularly, it has a structure in which a source and drain region of the non-volatile semiconductor memory device in formed in the semiconductor layer formed on the insulating layer and, at the same time, one of the read electrode and write electrode is buried in the insulating layer.

Abstract: A semiconductor integrated circuit device having a SOI structure which can prevent a deterioration in the breakdown voltage of a transistor without damaging integration, and a method for manufacturing the semiconductor integrated circuit device are obtained. An embedded oxide film is not formed over the whole face of a P type silicon layer but has an opening in a region which is placed below a gate electrode. The opening is filled in to form a penetration P layer. Accordingly, a SOI layer is electrically connected to the P type silicon layer through the penetration P layer. The plane position and shape of the gate electrode conform to those of the penetration P layer.

Abstract: A flash memory EEPROM transistor is formed on a surface of a semiconductor substrate. In portions of the substrate, at the surface thereof, a doped source region and a doped drain region are formed with a channel region therebetween. A tunnel silicon oxide dielectric layer is formed over the semiconductor substrate aside from the source region. Above the source region is formed a gate oxide layer which is thicker than the tunnel oxide layer. Above a portion of the tunnel oxide dielectric layer, over the channel region and above a portion of the gate oxide layer is formed a stacked-gate structure for the transistor comprising a floating gate layer, an interelectrode dielectric layer, and a control gate layer. The source region is located on one side of the stacked gate structure with one edge of the source region overlapping the gate structure. The drain region which is located on the other side of the stacked gate structure with one edge thereof overlapping the gate structure.

Abstract: An improved EEPROM structure is provided which has a longer data retention period. This is achieved by utilizing only positive charges to store data on the floating gate. The EEPROM structure includes a write select transistor (112), a read select transistor (120), and a floating gate sense transistor (126). The source of the write select transistor is capacitively coupled to the floating gate of the floating gate sense transistor via a tunnel oxide layer (145). The floating gate of the floating gate sense transistor is also capacitively coupled to a control gate line (CG) via a gate oxide layer (153). The sense transistor is formed as an enhancement transistor so as to allow the EEPROM structure to be operated in a region where the floating gate potential is positive for both programmed and erased conditions, thereby using only the positive charges to store data.