Abstract: The nonvolatile semiconductor memory device of the present invention includes: a semiconductor substrate having a surface including a first surface region at a first level, a second surface region at a second level lower than the first level, and a step side region linking the first surface region and the second surface region together; a channel region formed in the first surface region of the semiconductor substrate; a source region and a drain region which are formed in the surface of the semiconductor substrate so as to interpose the channel region therebetween; a first insulating film formed on the surface of the semiconductor substrate; a floating gate formed on the first insulating film; a second insulating film formed on the floating gate; and a control gate which is capacitively coupled to the floating gate via the second insulating film.

Abstract: A fast low voltage ballistic program, ultra-short channel, ultra-high density, dual-bit multi-level flash memory is described. The structure and operation of this invention is enabled by a twin MONOS cell structure having an ultra-short control gate channel of less than 40 nm, with ballistic injection which provides high electron injection efficiency and very fast program at low program voltages of 3˜5V. The ballistic MONOS memory cell is arranged in the following array: each memory cell contains two nitride regions for one word gate, and ½ a source diffusion and ½ a bit diffusion. Control gates can be defined separately or shared together over the same diffusion. Diffusions are shared between cells and run in parallel to the side wall control gates, and perpendicular to the word line.

Abstract: Provided in the present invention are a high speed and low program voltage nonvolatile memory cell, a programming method for same and a nonvolatile memory array. A nonvolatile memory cell comprises a first gate insulator formed on a surface of a first channel forming semiconductor region adjacent to a source region; a second gate insulator formed on a surface of a second channel forming semiconductor region adjacent to a drain region; a first gate electrode formed on said first gate insulator; and a second gate electrode formed on said second gate insulator wherein the second gate insulator includes a first layer forming a potential barrier at the interface with the second channel forming region; a third layer forming a potential barrier at the interface with the second gate electrode and the second layer between the first and third layers forming a carrier trapping level.

Abstract: A semiconductor memory device according to the present invention includes isolations, active regions, control gate electrodes and floating gate electrodes. The isolations are formed on a semiconductor substrate. The active regions are defined on the semiconductor substrate and isolated from each other by the isolations. The control gate electrodes are formed over the semiconductor substrate. Each of the control gate electrodes crosses all of the isolations and all of the active regions with a first insulating film interposed between the control gate electrode and the semiconductor substrate. Each of the floating gate electrodes is formed for associated one of the active regions so as to cover a side face of associated one of the control gate electrodes with a second insulating film interposed between the floating gate electrode and the control gate electrodes.

Abstract: A nonvolatile semiconductor memory device has a protective insulating film deposited on each of the side surfaces of a control gate electrode to protect the control gate electrode during the formation of a floating gate electrode, the floating gate electrode opposed to one of the side surfaces of the control gate electrode with the protective insulating film interposed therebetween so as to be capacitively coupled to the control gate electrode, a tunnel insulating film formed between the floating gate electrode and the semiconductor substrate, a drain region formed in a region of the semiconductor substrate containing a portion underlying the floating gate electrode, and a source region formed in a region of the semiconductor substrate opposite to the drain region relative to the control gate electrode.

Abstract: An fast program, ultra-high density, dual-bit, multi-level flash memory process, which can be applied to a ballistic step split gate side wall transistor, or to a ballistic planar split gate side wall transistor, which enables program operation by low voltage requirement on the floating gate during program is described. Two side wall floating gates are paired with a single word line select gate, and word lines are arranged to be perpendicular both the bit lines and control gate lines. Two adjacent memory cells on the same word line do not require an isolation region. Also, the isolation region between adjacent memory cells sharing the same bitline is defined by the minimum lithography feature, utilizing a self align fill technique. Adjacent memory cells on the same word line share bitline diffusion as well as a third poly control gate. Control gates allow program and read access to the individual floating gate.

Abstract: An fast program, ultra-high density, dual-bit, multi-level flash memory process, which can be applied to a ballistic step split gate side wall transistor, or to a ballistic planar split gate side wall transistor, which enables program operation by low voltage requirement on the floating gate during program is described. Two side wall floating gates are paired with a single word line select gate, and word lines are arranged to be perpendicular both the bit lines and control gate lines. Two adjacent memory cells on the same word line do not require an isolation region. Also, the isolation region between adjacent memory cells sharing the same bitline is defined by the minimum lithography feature, utilizing a self align fill technique. Adjacent memory cells on the same word line share bitline diffusion as well as a third poly control gate. Control gates allow program and read access to the individual floating gate.

Abstract: In a semiconductor substrate having a surface including a first surface region at a first level, a second surface region at a second level lower than the first level, and a step side region linking the first surface region and the second surface region together, a channel region has a triple structure. Thus, a high electric field is formed in a corner portion between the step side region and the second surface region and in the vicinity thereof. A high electric field is also formed in the first surface region. As a result, the efficiency, with which electrons are injected into a floating gate, is considerably increased.

Abstract: A semiconductor memory has first and second active regions that have been defined in a semiconductor substrate and electrically isolated from each other. Over the first active region, a control gate electrode has been formed with a control gate insulating film interposed therebetween. A floating gate electrode has been formed adjacent to a side face of the control gate electrode with a capacitive insulating film interposed therebetween. A tunnel insulating film is interposed between the first active region and the floating gate electrode. A gate electrode has been formed over the second active region with a gate insulating film interposed therebetween. Source/drain regions have been defined in respective parts of the second active region beside the gate electrode. Only the source/drain regions and the gate electrode have their upper surface covered with a metal silicide film.

Abstract: The nonvolatile semiconductor memory device of the present invention includes: a semiconductor substrate having a surface including a first surface region at a first level, a second surface region at a second level lower than the first level, and a step side region linking the first surface region and the second surface region together; a channel region formed in the first surface region of the semiconductor substrate; a source region and a drain region which are formed in the surface of the semiconductor substrate so as to interpose the channel region therebetween; a first insulating film formed on the surface of the semiconductor substrate; a floating gate formed on the first insulating film; and a control gate which is capacitively coupled to the floating gate via a second insulating film. The first insulating film includes a first gate insulating film portion formed in the first surface region, and, a second gate insulating film portion formed in the step side region and the second surface region.

Abstract: Provided in the present invention are a high speed and low program voltage nonvolatile memory cell, a programming method for same and a nonvolatile memory array. A nonvolatile memory cell comprises a first gate insulator formed on a surface of a first channel forming semiconductor region adjacent to a source region; a second gate insulator formed on a surface of a second channel forming semiconductor region adjacent to a drain region; a first gate electrode formed on said first gate insulator; and a second gate electrode formed on said second gate insulator wherein the second gate insulator includes a first layer forming a potential barrier at the interface with the second channel forming region; a third layer forming a potential barrier at the interface with the second gate electrode and the second layer between the first and third layers forming a carrier trapping level.

Abstract: A fast low voltage ballistic program, ultra-short channel, ultra-high density, dual-bit multi-level flash memory is described with a two or three polysilicon split gate side wall process. The structure and operation of this invention is enabled by a twin MONOS cell structure having an ultra-short control gate channel of less than 40nm, with ballistic injection which provides high electron injection efficiency and very fast program at low program voltages of 3˜5V. The cell structure is realized by (i) placing side wall control gates over a composite of Oxide-Nitride-Oxide (ONO) on both sides of the word gate, and (ii) forming the control gates and bit diffusion by self-alignment and sharing the control gates and bit diffusions between memory cells for high density.

Abstract: In a semiconductor substrate having a surface including a first surface region at a first level, a second surface region at a second level lower than the first level, and a step side region linking the first surface region and the second surface region together, a channel region has a triple structure. Thus, a high electric field is formed in a corner portion between the step side region and the second surface region and in the vicinity thereof. A high electric field is also formed in the first surface region. As a result, the efficiency, with which electrons are injected into a floating gate, is considerably increased.

Abstract: An electrically programmable read only memory device which has efficiency of electron injection from channel to floating gate is provided. This memory cell includes a control gate and floating gate between source and drain regions. The region under the floating gate has extremely small enhanced mode channel and N region. Therefore, this channel is completely depleted by the program drain voltage. The enhanced mode channel region is precisely defined by the side wall spacer technique. Also, the N drain region is accurately defined by the difference of side wall polysilicon gate and the first spacer.

Abstract: In a semiconductor substrate having a surface including a first surface region at a first level, a second surface region at a second level lower than the first level, and a step side region linking the first surface region and the second surface region together, a channel region has a triple structure. Thus, a high electric field is formed in a corner portion between the step side region and the second surface region and in the vicinity thereof. A high electric field is also formed in the first surface region. As a result, the efficiency, with which electrons are injected into a floating gate, is considerably increased.

Abstract: An electrically programmable read only memory device which has efficiency of electron injection from channel to floating gate is provided. This memory cell includes a control gate and floating gate between source and drain regions. The region under the floating gate has extremely small enhanced mode channel and N region. Therefore, this channel is completely depleted by the program drain voltage. The enhanced mode channel region is precisely defined by the side wall spacer technique. Also, the N drain region is accurately defined by the difference of side wall polysilicon gate and the first spacer.

Abstract: A fabrication method for an electrically programmable read only memory device, which consists of a control/word gate and a MONOS control gate on the side wall of the control gate. The unique material selection and blocking mask sequences allow simple and safe fabrication within the delicate scaled CMOS process environment, of a sidewall MONOS control gate with an ultra short channel under the control gate, which involves double side wall spacer formation i.e., a disposable side wall spacer and the final polysilicon spacer gate.

Abstract: A new FET device configuration for electrically programmable memories (EPROM), flash/electrically erasable and programmable read-only memories (EEPROM), and non-volatile Random Access Memory (NVRAM) which adds vertical components to a previously planar floating gate cell structure; efficiency of electron injection from the channel to floating gate is enhanced by many orders of magnitude because electrons accelerated in the channel penetraite in the direction of movement, straight into the floating gate. The floating gate resides over a series of arbitrary horizontal and vertical channel region components, the key topological feature being that the vertical channel resides near the drain, allowing electrons to penetrate straight into the floating gate. In contrast, the prior art relies on the indirect process of electron scattering by phonon and the 90 degree upward redirection of motion to the floating gate used by conventional Channel Hot Electron EPROM and EEPROM cells.

Abstract: The nonvolatile semiconductor memory device of the invention includes: a semiconductor substrate having a surface including a first surface region at a first level, a second surface region at a second level lower than the first level, and a step side region linking the first and second surface regions; a channel region formed in the first surface region of the semiconductor substrate; a source region and a drain region which are formed in the surface of the semiconductor substrate so as to interpose the channel region therebetween; a first insulating film formed on the surface of the semiconductor substrate; a floating gate formed on the first insulating film; and a control gate capacitively coupled to the floating gate via a second insulating film. The first surface region is an upper surface of an epitaxially grown layer formed on the second surface region.

Abstract: A field effect transistor (FET) device, which mitigates leakage current induced along the edges of the FET device, is isolated by shallow trench isolation having a channel width between a first and a second shallow trench at a first and second shallow trench edges. A gate extends across the channel width between the first and second shallow trenches. The gate has a first length at the shallow trench edges and a second length less than the first length between the shallow trench edges. The first length and the second length are related such that the threshold voltage, V.sub.t, at the shallow trench edges is substantially equal to V.sub.t between the shallow trench edges. The gate structure of the FET device is produced using a unique phase shift mask that allows the manufacture of submicron FET devices with very small channel lengths.