WO2006054605A1 - 不揮発性半導体記憶装置およびその製造方法 - Google Patents
不揮発性半導体記憶装置およびその製造方法 Download PDFInfo
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- WO2006054605A1 WO2006054605A1 PCT/JP2005/021047 JP2005021047W WO2006054605A1 WO 2006054605 A1 WO2006054605 A1 WO 2006054605A1 JP 2005021047 W JP2005021047 W JP 2005021047W WO 2006054605 A1 WO2006054605 A1 WO 2006054605A1
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- Prior art keywords
- floating gate
- memory device
- semiconductor memory
- control
- gate electrode
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Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10B—ELECTRONIC MEMORY DEVICES
- H10B41/00—Electrically erasable-and-programmable ROM [EEPROM] devices comprising floating gates
- H10B41/40—Electrically erasable-and-programmable ROM [EEPROM] devices comprising floating gates characterised by the peripheral circuit region
- H10B41/42—Simultaneous manufacture of periphery and memory cells
- H10B41/43—Simultaneous manufacture of periphery and memory cells comprising only one type of peripheral transistor
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C16/00—Erasable programmable read-only memories
- G11C16/02—Erasable programmable read-only memories electrically programmable
- G11C16/04—Erasable programmable read-only memories electrically programmable using variable threshold transistors, e.g. FAMOS
- G11C16/0408—Erasable programmable read-only memories electrically programmable using variable threshold transistors, e.g. FAMOS comprising cells containing floating gate transistors
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C16/00—Erasable programmable read-only memories
- G11C16/02—Erasable programmable read-only memories electrically programmable
- G11C16/06—Auxiliary circuits, e.g. for writing into memory
- G11C16/10—Programming or data input circuits
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/40—Electrodes ; Multistep manufacturing processes therefor
- H01L29/401—Multistep manufacturing processes
- H01L29/4011—Multistep manufacturing processes for data storage electrodes
- H01L29/40114—Multistep manufacturing processes for data storage electrodes the electrodes comprising a conductor-insulator-conductor-insulator-semiconductor structure
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/40—Electrodes ; Multistep manufacturing processes therefor
- H01L29/41—Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions
- H01L29/423—Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions not carrying the current to be rectified, amplified or switched
- H01L29/42312—Gate electrodes for field effect devices
- H01L29/42316—Gate electrodes for field effect devices for field-effect transistors
- H01L29/4232—Gate electrodes for field effect devices for field-effect transistors with insulated gate
- H01L29/42324—Gate electrodes for transistors with a floating gate
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/66007—Multistep manufacturing processes
- H01L29/66075—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
- H01L29/66227—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials the devices being controllable only by the electric current supplied or the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched, e.g. three-terminal devices
- H01L29/66409—Unipolar field-effect transistors
- H01L29/66477—Unipolar field-effect transistors with an insulated gate, i.e. MISFET
- H01L29/66825—Unipolar field-effect transistors with an insulated gate, i.e. MISFET with a floating gate
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10B—ELECTRONIC MEMORY DEVICES
- H10B41/00—Electrically erasable-and-programmable ROM [EEPROM] devices comprising floating gates
- H10B41/30—Electrically erasable-and-programmable ROM [EEPROM] devices comprising floating gates characterised by the memory core region
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10B—ELECTRONIC MEMORY DEVICES
- H10B41/00—Electrically erasable-and-programmable ROM [EEPROM] devices comprising floating gates
- H10B41/30—Electrically erasable-and-programmable ROM [EEPROM] devices comprising floating gates characterised by the memory core region
- H10B41/35—Electrically erasable-and-programmable ROM [EEPROM] devices comprising floating gates characterised by the memory core region with a cell select transistor, e.g. NAND
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10B—ELECTRONIC MEMORY DEVICES
- H10B41/00—Electrically erasable-and-programmable ROM [EEPROM] devices comprising floating gates
- H10B41/40—Electrically erasable-and-programmable ROM [EEPROM] devices comprising floating gates characterised by the peripheral circuit region
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10B—ELECTRONIC MEMORY DEVICES
- H10B69/00—Erasable-and-programmable ROM [EPROM] devices not provided for in groups H10B41/00 - H10B63/00, e.g. ultraviolet erasable-and-programmable ROM [UVEPROM] devices
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C16/00—Erasable programmable read-only memories
- G11C16/02—Erasable programmable read-only memories electrically programmable
- G11C16/04—Erasable programmable read-only memories electrically programmable using variable threshold transistors, e.g. FAMOS
- G11C16/0408—Erasable programmable read-only memories electrically programmable using variable threshold transistors, e.g. FAMOS comprising cells containing floating gate transistors
- G11C16/0416—Erasable programmable read-only memories electrically programmable using variable threshold transistors, e.g. FAMOS comprising cells containing floating gate transistors comprising cells containing a single floating gate transistor and no select transistor, e.g. UV EPROM
Definitions
- Nonvolatile semiconductor memory device and manufacturing method thereof are nonvolatile semiconductor memory devices and manufacturing method thereof.
- the present invention relates to a method for manufacturing a nonvolatile semiconductor memory device, and more particularly to a nonvolatile semiconductor memory device of a type that performs batch erase called a flash memory and a method for manufacturing the same.
- flash EEPROM flash electrically erasable and programmable read only memory
- Reference 1 Japanese Nishizawa “Semiconductor Terminology Dictionary”, Nikkan Kogyo (1999.3.20), pp.970-972.
- a stack type in which a control gate electrode is stacked on a floating gate is generally used. Its structure is shown in Figure 37A. As shown in FIG.
- a diffusion layer 202 constituting a source drain region is formed in a surface region of a p-type silicon substrate 201, and a silicon oxide film is formed on the substrate.
- a floating gate 204 is stacked via a gate insulating film 203, and further, for example, an ONO (silicon oxide film Z silicon nitride film Z silicon oxide film) structure intergate insulating film 205 is formed thereon.
- a control gate electrode 206 is laminated.
- Erase and write to this memory cell are performed as follows.
- the control gate electrode is grounded, the drain is floated, a voltage of 12 V is applied to the source, and a high electric field is applied to the gate insulating film 203.
- Fowler-Nordheim is performed by drawing out electrons accumulated in the floating gate 204 to the source.
- a ground potential and 5 V are applied to the source and drain, respectively, 12 V is applied to the control gate electrode 206, CHE (channel hot electron) is generated in the channel, and a part thereof is injected into the floating gate.
- One problem with conventional flash memories is that downsizing cannot be achieved according to the scaling law. The reason is that the charge injected into the floating gate must be maintained for about 10 years, for example, but the gate insulating film 203 cannot be reduced below a certain thickness in order to meet this requirement. In addition, writing and erasing are performed by injecting and extracting electrons through the gate insulating film, and this cycle degrades the insulating film. In order to suppress this deterioration and guarantee a certain number of cycles, the gate insulating film has reached its limit.
- the control gate electrode since the control gate electrode must control the channel potential via the floating gate, a high voltage of, for example, about 12 V is applied at the time of writing. This voltage is not lowered by downsizing. The reason is that even if the channel length is reduced, the gate insulating film cannot be thinned as described above. Conventionally, by increasing the channel impurity concentration, as a measure for punch-through for shortening the channel length, As a result, the threshold voltage rises, causing the gate voltage to rise. In order to prevent electrons from being extracted from the floating gate even when a high voltage is applied to the control gate electrode, the thickness of the inter-gate insulating film must be thicker than a certain value.
- Another problem with the conventional example is that there is a high risk of erroneous writing due to so-called gate disturb during writing.
- 12 V which is the same as that of the selected cell
- the control gate electrode of the non-selected cell connected to the same word line as the selected cell.
- the source of the unselected cell is grounded and the drain is floating.
- the object of the present invention is to solve the above-mentioned problems of the prior art.
- the purpose of the present invention is to first realize downsizing according to the scaling law. Secondly, it is possible to achieve a lower drive voltage, and thirdly, it is possible to provide a memory with a low risk of erroneous writing.
- a nonvolatile semiconductor memory device of the present invention includes a control gate electrode formed on a semiconductor substrate and a source / drain formed in a semiconductor substrate region sandwiching the control gate electrode.
- a switching element having a control transistor having a region, a lead line drawn from one of the source / drain regions, and a floating gate for controlling a conduction state of the lead line by a charge storage state thereof And having.
- a nonvolatile semiconductor memory device of the present invention includes a control gate electrode formed on a semiconductor substrate, and a source / drain region formed in a semiconductor substrate region sandwiching the control gate electrode.
- a control transistor having a bow I line formed of at least a part of a semiconductor material, and a bow I line formed in the vicinity of the bow I lead line from which the force on either one of the source / drain regions is drawn
- a switching element having a floating gate.
- a nonvolatile semiconductor memory device of the present invention includes a control transistor having a control gate electrode, and a switching having a floating gate connected in series with the control transistor. And the current path of the switching element is perpendicular to the surface of the semiconductor substrate and nearly perpendicular! Formed in a cocoon shape! Speak.
- the control gate electrode and the floating gate are not stacked, and the switching element is controlled by the floating gate using the drain lead line of the control transistor having the control gate electrode.
- the control gate electrode since the control gate electrode is directly opposed to the channel on the semiconductor substrate, the gate insulating film between them is required to have both retention and endurance. The thin film according to the scaling law becomes possible.
- the control gate electrode since the control gate electrode is directly opposed to the channel, the gate application voltage can be reduced due to the further reduction in the gate insulating film thickness and the channel concentration. Voltage can be realized.
- the gate disturb problem which has been a big problem in the conventional example, is alleviated.
- the gate insulating film of the control transistor since it is not always necessary to use a silicon oxide film as the gate insulating film on the silicon substrate, the gate insulating film of the control transistor has a high dielectric constant. It becomes possible to employ an edge film.
- FIG. 1A is a longitudinal sectional view of a main part of an embodiment of the present invention.
- FIG. 1B is a cross-sectional view of an essential part of the embodiment of the present invention.
- FIG. 1C and FIG. 1D are operation explanatory diagrams of the embodiment of the present invention.
- FIGS. 2A to 2D are cross-sectional views of relevant parts of Embodiment 1 of the present invention.
- FIGS. 3A to 3D are cross-sectional views of the essential parts of Embodiment 2 of the present invention.
- FIGS. 4A to 4D are cross-sectional views of main parts of Embodiment 3 of the present invention.
- FIGS. 5A to 5D are cross-sectional views of the essential parts of Embodiment 4 of the present invention.
- FIGS. 6A to 6D are cross-sectional views of the essential parts of Embodiment 5 of the present invention.
- FIGS. 7A to 7E are cross-sectional views of main parts of Embodiment 6 of the present invention.
- FIGS. 8A to 8D are cross-sectional views of the essential parts of Embodiment 7 of the present invention.
- FIGS. 9A to 9D are cross-sectional views of the essential portions of Embodiment 8 of the present invention.
- FIGS. 10A to 10D are cross-sectional views of the essential parts of Embodiment 9 of the present invention.
- FIGS. 11A to 11D are cross-sectional views of the essential parts of Embodiment 10 of the present invention.
- FIGS. 12A to 12D are cross-sectional views of the essential parts of Embodiment 11 of the present invention.
- FIG. 13A is a plan view of Example 11 of the present invention.
- FIG. 13B is a cross-sectional view of main parts of Example 11 of the present invention.
- FIGS. 14A to 14D are cross-sectional views of the essential parts of Embodiment 12 of the present invention.
- FIGS. 15A to 15D are cross-sectional views of the essential parts of Embodiment 13 of the present invention.
- FIGS. 16A to 16D are cross-sectional views of the essential parts of Embodiment 14 of the present invention.
- FIGS. 17A to 17D are cross-sectional views of the essential parts of Embodiment 15 of the present invention.
- FIGS. 18A to 18D are cross-sectional views of main parts of Embodiment 16 of the present invention.
- FIGS. 19A to 19D are cross-sectional views of the essential parts of Embodiment 17 of the present invention.
- FIGS. 20A to 20D are cross-sectional views of main parts of Embodiment 18 of the present invention.
- FIGS. 21A-D are cross-sectional views of main parts of Embodiment 19 of the present invention.
- FIGS. 22A to 22D are cross-sectional views of the essential parts of Example 20 of the present invention.
- FIGS. 23A to 23D are cross-sectional views of main parts of Embodiment 21 of the present invention.
- FIG. 24 is a diagram showing electron barriers and hole barriers of various insulating materials.
- FIGS. 25A to 25D are cross-sectional views of the essential parts of Example 22 of the present invention.
- FIG. 26A to FIG. 26M are cross-sectional views in order of steps showing Example 1 of the manufacturing method of the present invention.
- FIGS. 27A to 27F are cross-sectional views in order of steps showing Example 2 of the manufacturing method of the present invention.
- FIGS. 28A to 28G are cross-sectional views in order of steps showing Example 3 of the manufacturing method of the present invention.
- FIGS. 29A to 29F are cross-sectional views in order of steps showing Example 4 of the manufacturing method of the present invention.
- FIGS. 30A to 30F are cross-sectional views in order of steps showing Example 5 of the manufacturing method of the present invention.
- FIGS. 31A to 31C are cross-sectional views in order of steps showing Example 6 of the manufacturing method of the present invention.
- FIG. 32 is a cross-sectional view for explaining Example 7 of the manufacturing method of the present invention.
- FIGS. 33A to 33D are cross-sectional views in order of steps showing Example 8 of the manufacturing method of the present invention.
- FIGS. 34A to 34F are cross-sectional views in order of steps showing Example 9 of the manufacturing method of the present invention.
- FIGS. 35A-D are cross-sectional views in order of the steps showing Example 10 of the manufacturing method of the present invention.
- FIGS. 36A to 36D are cross-sectional views in order of the steps showing Example 11 of the manufacturing method of the present invention.
- FIG. 37A is a cross-sectional view of a conventional example.
- FIGS. 37B and 37C are diagrams for explaining the operation of the conventional example.
- FIG. 1A is a cross-sectional view of a memory cell showing an embodiment of the present invention
- FIG. 1B is a cross-sectional view taken along line AA of FIG. 1A
- 101 is a semiconductor substrate
- 102 is a diffusion layer that becomes a source drain region
- 103 is a control gate electrode
- 104 is a switching formed mainly by a semiconductor and controlled by a floating gate 105.
- a drain lead line 106 serving as a current path of the element
- a gate lead line 106 serving as a current path of the element
- a source lead line 107 a source lead line 107
- an interlayer insulating film 108 an interlayer insulating film
- the transistor constituted by the control gate electrode 103 and the diffusion layer 102 is a MOSFET having a normal structure, and can be designed in the same manner as a DRAM transistor. Therefore, the gate insulating film can be composed of a high dielectric constant insulating film.
- the left diffusion layer is referred to as a source
- the right diffusion layer is referred to as a drain in the present specification for the sake of convenience.
- the semiconductor substrate 101 a p-type silicon substrate or a silicon substrate having p-well is typically used.
- the semiconductor substrate 101 is not limited to this, and an SOI substrate or a silicon substrate having a SiGe layer may be used.
- the control gate electrode 103 is a wiring that becomes a word line in the cell array, and may be a polycide, silicide, or refractory metal for which n-type polysilicon is advantageously used.
- FN current or PF (Poole-Frenkel) current When the upper surface of the control gate electrode 103 and the lower surface of the floating gate 105 are opposed to each other and electrons are injected from the control gate electrode 103 to the floating gate using FN current or PF (Poole-Frenkel) current during writing.
- the write voltage can be lowered.
- metals that desirably have a work function of less than 4.
- leV include Sr, Y, Gd, Lu, Hf, Ti, Sm, Eu, Nd, Ce, Ba, Cs or those These alloys are mentioned.
- a silicide layer such as nickel silicide or cobalt silicide at the interface between the diffusion layer 102 serving as the source / drain region and the leader line.
- the silicide layer may be provided so as to cover the entire surface of the source / drain region, and when the contact hole is opened, the silicide layer should be formed at the bottom.
- the drain lead line 104 serves as a current path of the switching element having the floating gate 105 as described above, and may be formed of n-type polysilicon when the drain is an n-type diffusion layer. Further, np polysilicon or npn polysilicon may be used.
- n-i-p polysilicon, n-i-n polysilicon, mi-m, and m-S-m (i is an insulating film, m is a metal or silicide, and s is a semiconductor).
- the floating gate is located at a portion facing the i layer or the p layer when the drain lead line 104 includes the i layer or the npn structure, and at a portion facing the n layer in the other cases. Be placed.
- the i layer that is, the insulating film
- the semiconductor below the i layer can be formed of a single crystal silicon film.
- the impurity concentration of the n-type silicon film is preferably 1 ⁇ 10 18 / cm 3 or more in order to keep the drain extraction resistance low.
- the insulating film is made of a material having a low electron barrier when the carrier of the drain lead 104 is an electron, for example, BST (barium titanate). It is desirable to use (strontium), tantalum oxide, zirconium oxide, and hafnium oxide.
- BST barium titanate
- the carrier is a hole
- a material having a low hole barrier such as silicon nitride.
- the floating gate can be formed of non-doped polysilicon or doped polysilicon.
- a floating gate may be formed using a film (Al 2 O 3). The floating gate controls more current.
- the floating gate may be formed so as to partially overlap the control gate electrode.
- the control gate electrode may be formed so that a part thereof is placed on the floating gate. In this way, by providing the floating gate and the control gate electrode to overlap each other, it is possible to facilitate the injection and extraction of carriers from the control gate electrode to the floating gate.
- the floating gate may be formed of an electron trap film which is an insulator. Preferred materials for this purpose include aluminum oxide and silicon nitride. A ferroelectric film can also be used. In addition, it is desirable that the film thickness is small in order to increase the voltage change with respect to the change in the charge accumulated in the floating gate.
- the film thickness is preferably 50 nm or less.
- floating The gate is formed as a continuous film, but it can be formed as a large number of dots, if not.
- the gate lead line 106 and the source lead line 107 are made of doped polysilicon or W / Ti / TiN. Plug. These lead lines do not necessarily need to be provided for each cell, but one lead may be provided for multiple cells depending on the cell array configuration.
- the transistor is assumed to be an n-channel MOS transistor, and the drain lead line is assumed to be n-type polysilicon.
- reading is performed, for example, by applying 2V to the gate electrode, grounding the source lead line, and applying IV to the drain lead line.
- Fig. 1C and Fig. ID are diagrams showing the band state of the drain leader line.
- Fig. 1C shows the state when electrons are accumulated in the floating gate
- Fig. 1D shows that no electrons are accumulated in the floating gate. The state of the case is shown.
- the band in the region surrounded by the floating gate is lifted (pseudo-p-type), and an electron barrier is formed in that area. Current does not flow.
- the drain leader shows high resistance and only a small current flows. When electrons are not accumulated in the floating gate, a large current flows through the drain lead line where no electron barrier is formed in the drain lead line.
- the stored information is identified by detecting whether the current flowing through the drain lead line is on or off.
- Erasing is batch erasing and is performed by extracting carriers from the floating gate to the drain lead line or control gate electrode or drain lead line and control gate electrode.
- a positive high voltage is applied to the drain leader when extracting electrons to the drain leader.
- a ground potential or an appropriate intermediate potential is applied to the control gate electrode.
- a positive high voltage is applied to the control gate electrode when electrons are extracted to the control gate electrode.
- the drain lead line is set to ground potential or open. Further, when electrons are drawn out to both the drain lead line and the control gate electrode, a positive high voltage is applied to both.
- the substrate potential is preferably zero.
- the source is open or grounded.
- avalanche breakdown occurs in the drain lead and the hot carrier Erasing may be performed by rear injection.
- Writing is performed by hot electron injection, FN current, or PF current for each cell.
- CHE injection of a transistor having a control gate electrode
- a voltage is applied to the control gate electrode to turn on the transistor and a high voltage is applied to the drain to generate CHE and hot electrons to the floating gate. inject.
- CHE can be generated in the drain leader and used.
- the drain leader is p-type on the wiring side and n-type on the substrate side
- CHE is generated at the pn junction when a transistor with a control gate electrode is turned on and a negative voltage is applied to the drain leader. Can be made. Using this, hot electron injection is performed.
- nonvolatile memory devices include data buses, address buses, control lines, etc., and control circuits, address registers, program voltage generation circuits, erase control circuits, write circuits, sense amplifiers, input / outputs Circuits such as buffers are installed.
- Control signals such as WEbar, CEbar, and OEbar are input to the control circuit, and the control circuit controls the operation of each unit based on this control signal.
- An address signal is input to the address register from the outside, and this address signal is decoded by the X decoder and Y decoder.
- a word line of the memory cell array is selected by the X decoder, and a cell connected to the word line is selected.
- the memory cell is also connected to a bit line, and the bit line is selected by a Y gate controlled by a Y decoder and connected to a write circuit and a sense amplifier.
- the write circuit and sense amplifier are connected to the input / output buffer. When writing, the data input from the outside is input / output buffer and write circuit.
- the data is transmitted to the bit line via the path, and writing to the cell selected by the word line is performed.
- the signal read to the bit line is amplified by the sense amplifier and then output to the outside via the input / output buffer.
- the memory cells are erased in batches or in blocks in batches via the erase control circuit.
- the memory cell of the present invention can be individually erased.
- the memory cell according to the present invention can be used to construct such a single memory device, but it is used for a memory part formed on the same substrate together with a logic circuit part, so that a so-called mixed device is formed. It can also be used.
- FIGS. 2A to 2D are cross-sectional views showing the principal parts of Embodiment 1 of the present invention.
- FIG. 2A shows an erase operation
- FIG. 2B shows a write operation
- FIGS. 2C and 2D show a read operation.
- the state of the hour is shown.
- an n-type diffusion layer 2 serving as a source / drain region is formed in the surface region of the p-type silicon substrate 1, and a control gate electrode 3 is formed on the substrate.
- the entire substrate is covered with an interlayer insulating film 8.
- the drain lead line 4 which has n-type polysilicon force from the drain region 4 force control gate electrode 3
- the force lead is the same as the gate lead line 6 of the W / Ti / TiN structure from the source region.
- Source leader 7 of W / Ti / TiN structure is drawn out.
- the source is opened, the control gate electrode is grounded, + 6V is applied to the drain lead line, and a high electric field is applied to the gate insulating film between the floating gate and the drain lead line.
- the drain lead line is grounded, + 6V is applied to the control gate electrode, and a high electric field is applied to the insulating film between the floating gate control gate electrodes to extract the floating gate electrons to the control gate electrode. .
- a high voltage is applied to both the control gate electrode and the drain lead line, and an electron is extracted from both.
- FIGS. 3A to 3D are cross-sectional views showing the main part of Embodiment 2 of the present invention.
- FIG. 3A shows an erase operation
- FIG. 3B shows a write operation
- FIGS. 3C and 3D show a read operation.
- the state of is shown.
- 3A to 3D parts having the same functions as those in FIGS. 2A to 2D are denoted by the same reference numerals, and redundant description will be omitted as appropriate (the same applies to the following examples).
- 2A to 2D of the present embodiment is different from the first embodiment shown in FIG. 2A to FIG. 2D in that the cross section is formed in a crank shape so that the control gate electrode 3 and the floating floating gate 5 overlap.
- the gate 5 is formed so as to cover a part of the channel region of the transistor controlled by the control gate electrode 3.
- + 6V is applied to one of the control gate electrode 3 and the drain lead line 4, and the other is grounded, and between the floating gate and the drain lead line Alternatively, a high electric field is applied to the insulating film between the floating gate and the control gate electrode to draw the floating gate electron to the drain lead line 4 or the control gate electrode 3.
- + 2V is applied to the control gate electrode, the source is grounded, + 6V is applied to the drain lead line, CHE is generated in the transistor having the control gate electrode, and hot electrons are floated Inject into the gate.
- Reading is performed by applying + 2V to the control gate electrode, + IV to the source, and grounding the drain lead line.
- an electron barrier is not formed in the drain lead line, so that the switching element formed in the drain lead line is in the on state [FIG. 3C].
- an electron barrier is formed in the drain lead line and the current flowing through the drain lead line is suppressed.
- the current flowing through the channel of the transistor controlled by the control gate electrode 3 is also suppressed by the floating gate 5. That is, According to the cell structure of the present embodiment, when in the writing state, as shown in FIG. 3D, the current is suppressed at the points A and B in the figure.
- the present embodiment it becomes easier to identify the current ON Z OFF (or magnitude). Even in this embodiment, reading in the reverse read direction as shown in Embodiment 1 may be performed. At this time, needless to say, the voltage applied to the transistor is set to an optimum voltage for the reading. In the following embodiments, the force reverse read or forward read described for either one can be selected according to the intention of the circuit designer.
- FIGS. 4A to 4D are cross-sectional views showing the principal part of Embodiment 3 of the present invention.
- FIG. 4A shows an erase operation
- FIG. 4B shows a write operation
- FIGS. 4C and 4D show a read operation.
- the state of the hour is shown.
- the difference from the first embodiment shown in FIGS. 2A to 2D of the present embodiment is that a polysilicon film is included in the sidewall formed on the side surface of the control gate electrode 3, and the polysilicon is formed on the drain lead line side.
- the silicon film is combined with the floating gate 5 to become a part of the floating gate. That is, the sidewall silicon film 9 formed on the side surface of the control gate electrode 3 becomes a part of the floating gate 5 on the drain lead line side.
- the erase method, write method, and read method of this example are the same as those of Example 2.
- FIG. 5A to FIG. 5D are cross-sectional views showing the main part of Embodiment 4 of the present invention.
- FIG. 5A shows an erase operation
- FIG. 5B shows a write operation
- FIG. 5C and FIG. The state of the hour is shown.
- the difference from Example 1 shown in FIGS. 2A to 2D of this example is that the section of the part is formed in a ⁇ shape so that the floating gate 5 and the control gate electrode 3 overlap. is there With this configuration, it becomes possible to control the distance between the control gate electrode 3 and the floating gate 5 with high accuracy. For example, when the electrons of the floating gate are extracted to the control gate electrode during erasing, The variation in cell characteristics can be suppressed by reducing the variation in charge at the floating gate.
- the erase method, write method, and read method of this example are the same as those of Example 2.
- FIGS. 6A to 6D are cross-sectional views showing the main part of the fifth embodiment of the present invention.
- FIG. 6A shows an erase operation
- FIG. 6B shows a write operation
- FIGS. 6C and 6D show a read operation.
- the state of the hour is shown.
- 5A to 5D of the present embodiment is that the lower part of the control gate electrode 3 is made of the polysilicon film 3a, and the upper part, that is, the part facing the floating gate 5 is the metal film 3b. It is a point formed by.
- the metal film 3b is formed of a metal having a low work function.
- the erasing method and the reading method of the present embodiment are the same as those of the fourth embodiment, and the force writing is performed by the FN current from the control gate electrode 3. That is, electrons are injected from the control gate electrode 3 by applying ⁇ 2 V to the control gate electrode and +4 V to the drain lead line.
- the writing voltage can be lowered.
- current consumption for writing can be kept low.
- FIG. 7A to FIG. 7E are cross-sectional views showing the principal parts of Embodiment 6 of the present invention.
- FIG. 7A shows an erase state
- FIG. 7B shows a write time
- FIG. 7C and FIG. Fig. 7E shows a cross section of the contact part.
- 2A to 2D of the present embodiment is different from the first embodiment shown in FIGS. 2A to 2D in that a write / erase control wiring is provided at a position adjacent to the control gate electrode, and between the control gate electrode and the write / erase control wiring. This is the point where the drain leader is formed. That is, as shown in FIGS.
- a write / erase control wiring 11 having the same shape as that of the control gate electrode 3 is provided on the element isolation region 10 and the write / erase control wiring 11 is programmed.
- the lead-out line 12 for the erasure control is taken out.
- a floating gate 5 and a drain lead line 4 are formed between the control gate electrode 3 and the write / erase control wiring 11.
- the space between the control gate electrode and the write / erase control wiring itself is used as a contact hole, it is possible to eliminate the effect of misalignment by opening the contact hole by a method such as self-line contact. Thus, the positional accuracy of the contact can be improved. Then, the contact portion can be formed into an elongated shape by using the self-alignment method, and the controllability by the floating gate can be improved. Further, when the leader line is taken out from the write / erase control wiring 11, erasing and writing can be performed more efficiently by utilizing the write / erase control wiring.
- Reading is performed by grounding the drain lead line and write / erase control wiring, and applying + 2V to the control gate electrode and + IV to the source.
- the cell When the cell is in the erased state, no electron barrier is formed on the drain leader, so the switching element formed on the drain leader is in the on state [Fig. 7C].
- the floating gate and the write / erase control wiring are shown not to overlap each other. However, the floating gate may be partially formed on the write / erase control wiring. In this case, the upper surface of the write / erase control wiring may be a metal film. The conditions for the metal material are the same as in Example 5 (FIGS. 6A to 6D).
- FIGS. 8A to 8D are cross-sectional views showing the principal parts of Embodiment 7 of the present invention.
- FIG. 8A shows a state during erasure
- FIG. 8B shows a state during writing
- FIGS. 8C and 8D show a read state.
- the state of the hour is shown.
- 2A to 2D of the present embodiment is different from the first embodiment shown in FIG. 2A to FIG. 2D in that the portion of the drain lead line 4 facing the floating gate 5 and the polysilicon film below it are the n-type polysilicon film 4a.
- the polysilicon film force in the upper part is a three-dimensional polysilicon film 4b.
- the position of the pn junction of the drain lead 4 does not need to be exactly coincident with the top of the floating gate 5.
- the source is opened, + 6V is applied to one of the control gate electrode 3 and the drain lead line 4, the other is grounded, and the floating gate drain lead A high electric field is applied to the insulating film between the lines or between the floating gate and the control gate electrode, and the electrons of the floating gate are extracted to the drain lead line 4 or the control gate electrode 3.
- + 2V is applied to the control gate electrode, the source is grounded, 4V is applied to the drain lead line, CHE is generated at the junction of the drain lead line 4, and hot electrons are generated. Inject into the floating gate (see band diagram on the right).
- Reading is performed by applying + 2V to the control gate electrode, grounding the source, and applying, for example, + 2V to the drain lead line (reverse read).
- the p-type conduction band height becomes equal to or lower than that of the n-type polysilicon film 4a. Therefore, no electronic barrier is formed at the pn junction in the reverse lead direction, and no electronic barrier is formed on the n-type Si near the end of the floating gate.
- the device is in the on state [ Figure 8C].
- the switching element formed by raising the band of the n-type polysilicon film 4a and forming an electron barrier at the end of the floating gate close to the substrate side of the drain lead line and the drain lead line. Is turned off [Fig. 8D].
- FIG. 9A to FIG. 9D are cross-sectional views showing the principal parts of Embodiment 8 of the present invention.
- FIG. 9A shows an erase operation
- FIG. 9B shows a write operation
- the state of the hour is shown.
- 8A to 8D of this embodiment is different from the embodiment 7 shown in FIG. 8A to FIG. 8D in that the floating gate 5 is cross-sectionally formed in a ⁇ shape so that the floating gate 5 partially overlaps the control gate electrode 3. It is a point.
- This embodiment combines the features of Embodiment 4 (FIGS. 5A to 5D) and Embodiment 7 (FIGS. 8A to 8D).
- FIG. 10A to FIG. 10D are cross-sectional views showing the principal part of Embodiment 9 of the present invention.
- FIG. 10A shows an erase operation
- FIG. 10B shows a write operation
- FIG. 10C and FIG. The state of the hour is shown.
- the difference from the seventh embodiment shown in FIGS. 8A to 8D of the present embodiment is that the control gate
- the silicon film is formed on the side wall formed on the side surface of the electrode 3, and the side wall silicon film 9 is combined with the floating gate and used as a part of the floating gate.
- This embodiment combines the features of Embodiment 3 (FIGS. 4A to 4D) and Embodiment 7 (FIGS. 8A to 8D).
- FIG. 11A to FIG. 11D are cross-sectional views showing the principal parts of Embodiment 10 of the present invention.
- FIG. 11A shows an erase operation
- FIG. 11B shows a write operation
- the state at the time of reading is shown.
- 8A to 8D of the present embodiment is different from the embodiment 7 shown in FIG. 8A to FIG. 8D in that a write / erase control wiring is provided at a position adjacent to the control gate electrode, and between the control gate electrode and the write erase control wiring.
- the drain leader line is formed in That is, as shown in FIGS. 11A to 11D, a write erase control wiring 11 having the same shape as the control gate electrode 3 is provided on the element isolation region 10, and the write erase control wiring 11 is changed to the write erase control wiring 11.
- a floating gate 5 and a drain lead line 4 are formed between the control gate electrode 3 and the write / erase control wiring 11.
- This embodiment combines the features of Embodiment 6 (FIGS. 7A to 7E) and Embodiment 7 (FIGS. 8A to 8D).
- the source is opened, and + 4V, + 6V, and OV are applied to the control gate electrode 3, the drain lead line 4, and the write erase control wiring lead line 12, respectively.
- a high electric field is applied to the gate insulating film between the floating gate and drain lead lines on the write / erase control wiring side, and electrons in the floating gate are extracted to the drain lead line 4. For example, if the entire cell is set to such a voltage setting, the entire cell can be erased collectively.
- the source is grounded, + IV is applied to the control gate electrode 3 to turn on the transistor, and the drain lead line 4 and the write / erase control wiring lead line 12 are each 4V, Apply + 6V and inject the hot-elect hole generated in the drain lead wire 4 into the floating gate near the write / erase control wiring.
- the drain lead line 4 and the write / erase control wiring lead line 12 are each 4V, Apply + 6V and inject the hot-elect hole generated in the drain lead wire 4 into the floating gate near the write / erase control wiring.
- a negative voltage for example, 6 V
- the feature of this structure is that a high voltage can be applied to the write / erase control wiring without considering the deterioration of the gate insulating film of the control transistor because the write / erase control wiring is arranged on the element isolation region. Therefore, for example, efficient electron injection can be realized at the time of writing.
- FIGS. 12A to 12D are cross-sectional views showing the principal parts of Embodiment 11 of the present invention.
- FIG. 12A shows an erase operation
- FIG. 12B shows a write operation
- FIGS. 12C and 12D show a read operation.
- the state of the hour is shown.
- the difference from Example 10 shown in FIGS. 11A to 11D of this embodiment is that no wiring is provided for the write / erase control wiring, and the write / erase control wiring is in a floating state. It is that you are.
- the source is opened, + 6V is applied to either of the control gate electrode 3 and the drain lead line 4, and V or the other is grounded, and the floating gate electrons are grounded. Is pulled out to the control gate electrode 3 or the drain lead wire 4.
- the source is grounded, + 3V and 14V are applied to the control gate electrode 3 and the drain lead line 4, respectively, and hot electrons generated in the drain lead line 4 are moved closer to the control gate electrode. Inject into the floating gate.
- Reading is performed, for example, by applying + 2V to the drain lead line, + 2V to the control gate electrode, and grounding the source (reverse read).
- FIG. 13A is a layout diagram of a cell array according to Embodiment 11 of the present invention
- FIG. 13B is a cell sectional view.
- the active region 13 partitioned by the element isolation region 10 is formed inclined with respect to the wiring laying direction.
- a write / erase control wiring 11 extending in the vertical direction is arranged on the substrate, and word lines 3A serving as control gate electrodes are provided on both sides thereof.
- bit lines 14 and source lines 15 extending in the horizontal direction are alternately arranged.
- the bit line 14 and the source line 15 are connected to the diffusion layer formed in the active region 13 through the drain lead line 4 and the source lead line 7 respectively.
- FIGS. 14A to 14D are cross-sectional views showing the main part of Embodiment 12 of the present invention.
- FIG. 14A shows an erase operation
- FIG. 14B shows a write operation
- FIGS. 14C and 14D show a read operation.
- the state of the hour is shown.
- the difference from the seventh embodiment shown in FIGS. 8A to 8D of this embodiment is that the entire floating gate 5 is formed higher than the control gate electrode 3.
- FIG. 15A to FIG. 15D are cross-sectional views showing the principal parts of Embodiment 13 of the present invention.
- FIG. 15A shows an erase operation
- FIG. 15B shows a write operation
- FIG. 15C and FIG. The state of the hour is shown.
- 8A to 8D of the present embodiment is different from Embodiment 7 shown in FIGS. 8A to 8D in that the cross section is formed in a crank shape so that the control gate electrode 3 and the floating floating gate 5 overlap each other.
- the gate 5 is formed so as to cover a part of the channel region of the transistor controlled by the control gate electrode 3.
- + 6V is applied to one of the control gate electrode 3 and the drain lead line 4! ], Ground the other and apply a high electric field to the insulating film between the floating gate and the drain lead line or between the floating gate and the control gate electrode to tl the floating gate electrons to the drain lead line 4 or the control gate electrode 3 Pull out.
- + 2V is applied to the control gate electrode
- the source is grounded
- + 6V is applied to the drain lead line
- CHE is generated in the transistor having the control gate electrode
- hot electrons are floated Inject into the gate.
- CHE can be generated on the drain leader line for writing.
- the source is grounded, + 3V and –3V are applied to the control gate electrode and drain lead line, respectively, CHE is generated in the drain lead line, and hot electrons are injected into the floating gate.
- Reading is the same as in Example 7 (Figs. 8A to 8D).
- the current flowing through the drain lead line is suppressed and at the same time controlled by the control gate electrode 3
- the floating gate 5 also suppresses the current flowing through the transistor channel.
- FIGS. 16A to 16D are cross-sectional views showing the main part of Embodiment 14 of the present invention.
- FIG. 16A shows an erase operation
- FIG. 16B shows a write operation
- FIGS. 16C and 16D show a read operation.
- the state of the hour is shown.
- 9A to 9D of the present embodiment is different from the embodiment 8 shown in FIGS. 9A to 9D in that the lower part of the control gate electrode 3 is formed by the polysilicon film 3a and the upper part, that is, the part facing the floating gate 5 is formed by the metal film 3b. It is a point that has been.
- the metal film 3b is formed of a metal having a low work function.
- the formation of the metal film has an advantage that the voltage at the time of writing can be reduced, but the operation itself can be realized by applying a high voltage without forming the metal film.
- Example 5 has the features of Example 5 (FIGS. 6A to 6D) and Example 7 (FIGS. 8A to 8D).
- the erasing method, the writing method, and the reading method are the same as those of Example 5. It may be the same as in the case of.
- a hot electron may be generated by a control transistor and injected into the floating gate.
- hot electrons may be generated at the drain lead line pn junction and injected into the floating gate.
- a method of generating a hot hole at the pn junction and injecting it into the floating gate is also used. be able to.
- the read method may be forward read.
- FIG. 17A to 17D are cross-sectional views showing the principal parts of Embodiment 15 of the present invention.
- FIG. 17A shows an erase operation
- FIG. 17B shows a write operation
- FIGS. 17C and 17D show a read operation.
- the state of the hour is shown.
- 2A to 2D of the present embodiment is different from the first embodiment shown in FIGS. 2A to 2D in that the region force 3 ⁇ 4 type polysilicon film 4b surrounded by the floating gate 5 of the drain lead line 4 is formed in the other regions. Is an n-type polysilicon film 4a.
- erasing is performed by creating an over-erased state. That is, at the time of erasing, as shown in FIG. 17A, the source is open (or grounded), + 8V is applied to either one of the control gate electrode 3 and the drain lead line 4, and the other is grounded. , Floating gate Apply a high electric field to the insulating film between the drain lead lines or between the floating gate and the control gate electrode to pull the floating gate electrons to the drain lead line 4 or the control gate electrode 3 Remove and accumulate holes in the floating gate.
- the floating gate is formed using n-type polysilicon in order to easily create an over-erased state. At the time of writing, as shown in FIG.
- + 2V is applied to the control gate electrode to turn on this transistor, the drain lead line is grounded, and 1V is applied to the source to generate at the drain lead line 4.
- Hot electrons are injected into the floating gate by CHE. When the holes accumulated in the floating gate disappear, the current flowing through the transistor disappears and the writing is completed.
- Writing can also be performed with the drain leader line open. Writing can also be performed by reversing the voltage applied to the source and drain leader lines.
- the source is grounded, + 2V is applied to the gate, + 8V is applied to the drain, and the erase operation is stopped by detecting the current flowing when erasure is completed. You can do it.
- Reading is performed by applying + 2V to the control gate electrode, + IV to the source, and grounding the drain lead line. Since holes are accumulated in the floating gate when the cell is in the erased state, the band of the p-type polysilicon film 4b of the drain lead line 4 surrounded by the floating gate is pulled down, and the drain lead line The electron barrier is not formed, and the switching element formed in the drain lead line is turned on [FIG. 17C]. When the cell is written, no charge is accumulated in the floating gate, and the p-type polysilicon film 4b forms an electron barrier on the drain lead line, thereby suppressing the current flowing through the drain lead line. [Figure 17D]. The band state of the drain leader line when on and off is shown on the right side of each figure.
- FIGS. 18A to 18D are main part sectional views showing Embodiment 16 of the present invention.
- FIG. 18A shows an erase state
- FIG. 18B shows a write state
- FIGS. 18C and 18D show a read state. It is shown.
- the difference from the embodiment 15 shown in FIGS. 17A to 17D of the present embodiment is that the drain leader p-type polysilicon film 4b and the floating gate 5 are formed above the control gate electrode 3.
- the p-type polysilicon film 4b is formed in an inverted T-shaped cross section
- the floating gate is formed in a ⁇ -shaped cross section.
- FIGS. 19A to 19D are cross-sectional views showing the main part of Embodiment 17 of the present invention.
- FIG. 19A shows an erase operation
- FIG. 19B shows a write operation
- FIGS. 19C and 19D show a read operation.
- the state of the hour is shown.
- This embodiment differs from the embodiment 15 shown in FIGS. 17A to 17D in that the cross section is formed in a crank shape so that the control gate electrode 3 overlaps the floating floating gate 5 and the floating gate 5 However, it is formed so as to cover a part of the channel region of the transistor controlled by the control gate electrode 3.
- the erasing method and reading method of the present example are the same as those of Example 15 (FIGS. 17A to 17D).
- writing is performed by hot electron injection. That is, as shown in Fig. 19B, 4V is applied to the source, + 5V is applied to the control gate electrode, the drain lead line is grounded (or opened), CHE is generated in the channel, and writing is performed. As programming progresses, the current decreases, the current stops flowing and the write is complete.
- FIGS. 20A to 20D are cross-sectional views showing the main part of Embodiment 18 of the present invention.
- FIG. 20A shows an erase operation
- FIG. 20B shows a write operation
- FIGS. 20C and 20D show a read operation.
- the state of the hour is shown.
- the difference from Example 15 shown in FIGS. 17A to 17D of the present example is that floating gate 5 is formed so as to overlap with part control gate electrode 3, and the cross section of the part is formed in a ⁇ shape. ⁇ ⁇ .
- the erase method, write method, and read method of the present example are the same as those of Example 17.
- FIGS. 21A to 21D are cross-sectional views showing the main part of Embodiment 19 of the present invention.
- FIG. 21A shows an erase operation
- FIG. 21B shows a write operation
- FIGS. 21C and 21D show a read operation.
- the state of the time indicates It is.
- the difference from the embodiment 15 shown in FIGS. 17A to 17D of this embodiment is that the p-type polysilicon film 4b of the drain lead line is formed at a position higher than the control gate electrode 3, and its cross-sectional area force n This is that the cross-sectional area of the part other than the connection part of the p-type polysilicon film 4a to the p-type polysilicon film 4b is larger.
- the erase method, write method, and read method of this example are the same as those of Example 16 (FIGS. 18A to 18D).
- FIG. 22A to FIG. 22D are cross-sectional views showing the principal part of Embodiment 20 of the present invention.
- FIG. 22A shows an erase operation
- FIG. 22B shows a write operation
- FIG. 22C and FIG. The state of the hour is shown.
- the difference from Example 15 shown in FIGS. 17A to 17D of this example is that the p-type polysilicon film of the drain lead line is replaced with the insulating film 4c, the film thickness is reduced, and the control gate is changed. The position is higher than the electrode 3!
- erasing is performed by creating an over-erased state. That is, at the time of erasing, as shown in FIG. 22A, the source and the control gate electrode 3 are grounded, + 8V is applied to the drain lead line 4, and a high electric field is applied to the insulating film between the floating gate drain lead lines to float The gate electrons are extracted to the drain lead line 4 to accumulate holes in the floating gate.
- + 2V is applied to the control gate electrode to turn on this transistor, the drain lead line is grounded, 6V is applied to the source, and electrons are injected into the floating gate.
- the source is grounded, + 2V is applied to the gate, + 8V is applied to the drain, and the erase operation is stopped by detecting the current flowing when erasure is completed. You may do it.
- Reading is performed by applying + 2V to the control gate electrode, + IV to the source, and grounding the drain lead line (forward read).
- the band of the insulating film 4c of the drain lead line 4 surrounded by the floating gate is pulled down, and the electron barrier formed here disappears or is in a low state
- the switching element formed at the drain lead line is turned on [Fig. 22C].
- the cell is written, no charge is accumulated in the floating gate, and the drain is formed by the insulating film 4c. An electron barrier is formed in the lead line and the current flowing through the drain lead is suppressed [FIG. 22D]. Even with this structure, reverse read is possible.
- FIGS. 23A to 23D are cross-sectional views showing the main part of Embodiment 21 of the present invention.
- FIG. 23A shows an erase operation
- FIG. 23B shows a write operation
- FIGS. 23C and 23D show a read operation.
- the state of the hour is shown.
- the difference from Example 7 shown in FIGS. 8A to 8D of this example is that an insulating film 4c is inserted between the n-type polysilicon film 4a and the p-type polysilicon film 4b of the drain lead line,
- the floating gate 5 is formed so as to surround the insulating film 4c.
- erasing is performed by creating an over-erased state. That is, at the time of erasing, as shown in FIG. 23A, the source and the control gate electrode 3 are grounded, +6 V is applied to the drain lead line 4, and a high electric field is applied to the insulating film between the floating gate drain lead lines to float The gate electrons are extracted to the drain lead line 4 to accumulate holes in the floating gate.
- + 2V is applied to the control gate electrode to turn on this transistor, the drain lead line is grounded, 6V is applied to the source, and electrons are injected into the floating gate. When the holes accumulated in the floating gate disappear, the current flowing through the transistor disappears and the writing is completed.
- writing can be performed while applying a voltage of about + 2V.
- writing can be performed by exchanging the voltage applied to the drain lead line and the voltage applied to the source lead line.
- Reading is performed by applying + 2V to the control gate electrode, grounding the source, and connecting to the drain lead line. + Carry out 2V. Since holes are accumulated in the floating gate when the cell is in the erased state, the band of the insulating film 4c of the drain lead line 4 surrounded by the floating gate is pulled down, and the electron barrier formed here disappears. It becomes low and the electrons move as shown by the solid arrows. In addition, when reading is performed by applying ⁇ 2 V to the drain lead line, electrons move as shown by the dotted arrow [FIG. 23C]. When the cell is written, no electric charge is accumulated in the floating gate, and an electron barrier is formed on the drain lead line by the insulating film 4c, and the current flowing through the drain lead line is suppressed [Fig. 23D]. .
- an insulating film is inserted into the drain lead line is one of the examples (FIG. 8A to FIG. 16D) having the force drain lead line joint 11 showing only two of Example 20 and Example 21.
- an insulating film can be inserted at the junction, and any p-type polysilicon film in the embodiment having the npn structure (FIGS. 17A to 21D) can be replaced with an insulating film (however, Change the film thickness if necessary).
- the driving method can be performed in the same manner as in the case of the embodiment having a pn junction or the embodiment having an npn structure.
- the contact portion excluding the insulating film may be formed of metal or metal silicide.
- the drain lead line even when the npn structure is used, the above-described device operation can be realized even if a metal or metal silicide structure is used except for p-type Si.
- the insulating film inserted into the drain lead line is preferably made of a material having a low electron barrier in order to increase the electric conductivity of the drain lead line.
- FIG. 24 is a diagram showing the height of the barrier of various insulating materials, and the numbers indicate the height of the electron barrier and the height of the hole barrier relative to silicon.
- An insulating material used in the drain lead line of the present invention is Ta O surrounded by a dotted line.
- BST is also higher than Ta O
- FIGS. 25A to 25D are cross-sectional views showing the principal part of the twenty-second embodiment of the present invention.
- FIG. 25A shows an erase operation
- FIG. 25B shows a write operation
- FIGS. 25C and 25D show a read operation.
- the state of the hour is shown.
- 7A to 7E of this embodiment is different from the embodiment 6 shown in FIG. 7A in that an insulator floating gate 5A having AlO serving as an electron trap film instead of a floating gate using polysilicon is used.
- the source is opened, 0V is applied to the control gate electrode and write erase control wiring, and + 8V is applied to the drain leader line, and between the insulator floating gate drain leader line High electric field is applied to the gate insulating film!] And the electrons in the insulator floating gate are drained. Pull out to the lead wire.
- the source is open, + 6V is applied to the control gate electrode and write / erase control wiring, and –4V is applied to the drain lead line, and electrons are transferred to the insulator floating gate 5A by the FN current. inject.
- an alumina or silicon nitride film sandwiched with a silicon oxide film, a hafnium-based oxide film, an oxynitride film, or a zirconium-based oxide film is suitable.
- the force ferroelectric material described for the electron trap to the insulating film may be used instead of the insulator floating gate material.
- PZ T lead zirconate titanate
- SBT bismuth strontium tantalate
- Reading is the same as in the sixth embodiment.
- 26A to 26M are cross-sectional views in order of the process showing Example 1 of the manufacturing method.
- an element isolation region 10 that partitions the active region is formed by shallow trench isolation (STI) or the like [FIG. 26A].
- STI shallow trench isolation
- polysilicon is deposited, phosphorus is ion-implanted to reduce resistance, and then patterned using a photolithography method on the active region.
- the control gate electrode 3 and the write / erase control wiring 11 are formed on the element isolation region 10 [FIG. 26B].
- silicon oxide is deposited and anisotropic etching is performed to form side walls on the side surfaces of the control gate electrode 3 and the write / erase control wiring 11, and ion implantation is performed using the control gate electrode and the side walls as masks.
- an n-type diffusion layer 2 to be a source / drain region is formed [FIG. 26C].
- silicon oxide is deposited to form the first interlayer insulating film 8a [FIG. 26D].
- the first interlayer insulating film 8a and the sidewalls are selectively etched away by photolithography to open a contact hole over the drain region [FIG. 26E].
- a protective insulating film 16 composed of a three-layer film of silicon oxide, silicon nitride, and silicon oxide is formed [FIG. 26F].
- polysilicon is deposited and anisotropic etching is performed to form the floating gate 5.
- thermal oxidation is performed and nitrogen
- a second gate insulating film 17 is formed by depositing a silicon nitride film and performing anisotropic etching [FIG. 26G].
- thermal oxidation is performed to convert the upper part of the floating gate into a silicon oxide film 18 (FIG. 26H).
- the protective insulating film 16 is etched back to expose the substrate surface [FIG. 261].
- surface treatment such as cleaning and dilute hydrofluoric acid treatment, an n-type polysilicon film 19 ⁇ is deposited [FIG. 26J].
- the n-type polysilicon film 19 ⁇ is patterned by a photolithography method to form the drain lead line 4 [FIG. 26 (b)].
- an insulating film such as a silicon oxide film is deposited to form the second interlayer insulating film 8b.
- CMP chemical mechanical polishing
- the interlayer insulating film 8b is selectively removed by etching to form a contact hole on the source region.
- W is deposited to fill the contact hole, and echino-knock (or CMP) is performed to form the source lead 7 [FIG. 26L].
- a metal film such as A1 is deposited by sputtering and patterned to form the metal wiring 20, and further an insulating film is deposited on the entire surface to form a third interlayer insulating film 8c [FIG. 26M].
- the floating gate and the second gate insulating film are formed by separate etching processes, but they may be formed in a lump. That is, after processing into the state of FIG. 26F, after polysilicon deposition, thermal oxidation, and silicon nitride deposition, etch back may be performed collectively to process into the state of FIG. 26G. Also, omit thermal oxidation of polysilicon or deposit silicon oxide.
- FIG. 27A to FIG. 27F are cross-sectional views in order of steps for explaining the second embodiment of the manufacturing method. Since the process up to the middle of this example is the same as the process shown in FIGS. 26A to 26J of Example 1, the illustration and description thereof are omitted, and the state of FIG. 26J is shown in FIG. 27A.
- the n-type polysilicon film 19n is etched back to the middle of the contact hole to form the n-type polysilicon film 4a of the drain lead line [FIG. 27B].
- a p-type polysilicon film 19p is deposited [FIG. 27C].
- the p-type polysilicon film 19p is etched back and buried in the contact hole.
- Film 4b is formed [FIG. 27D].
- an insulating film such as a silicon oxide film is deposited to form a second interlayer insulating film 8b, which is selectively etched away to open contact holes on the source region and the drain lead line 4. To do.
- the drain lead pn junction is formed by depositing p-type polysilicon, but instead of this method, p-type impurity ion implantation is performed in the state shown in FIG. 27A. To form a pn junction.
- the drain lead line may be formed of single crystal silicon. That is, from the state before the n-type polysilicon film 19 ⁇ is deposited (the state shown in FIG. 261), ⁇ -type single crystal silicon is grown on the drain region using the selective growth method, and doping impurities are ⁇ Switching to the mold, the drain lead of the single crystal silicon film with pn junction is formed.
- FIGS. 26A to 26E of Embodiment 1 are cross-sectional views in order of the steps for explaining the third embodiment of the manufacturing method.
- the steps up to the middle of this embodiment are the same as the steps shown in FIGS. 26A to 26E of Embodiment 1, and therefore illustration and description thereof are omitted, and the state of FIG. 26E is shown in FIG. 28A.
- a three-layer film of acid silicon, acid aluminum, and silicon oxide is formed and etched back.
- An insulator floating gate 5A having an electron trap film is formed [FIG. 28B].
- an n-type polysilicon film 4a with a drain lead is formed in the contact hole by depositing n-type polysilicon and etching back [FIG. 28C].
- an n-type single crystal silicon film may be formed by selective growth.
- a second interlayer insulating film 8b is formed, and the second interlayer insulating film 8b on the drain region is selectively removed by photolithography [FIG. 28D].
- p-type polysilicon is deposited and etched back (or CMP) to bury the polysilicon in the second interlayer insulating film 8b and to form a drain lead p-type polysilicon.
- a film 4b is formed (FIG. 28E).
- a contact hole is opened on the source region, TiN, Ti, and W are sequentially deposited, and etch back (or CMP) is performed to form a W plug that becomes the source lead 7 [FIG. 28F].
- etch back or CMP
- silicon oxide is used as the electron trap film, but silicon nitride may be used instead.
- 29A to 29F are cross-sectional views in order of the steps showing Example 4 of the manufacturing method.
- an element isolation region 10 for partitioning an active region is formed, a gate insulating film is formed by thermal oxidation, polysilicon is deposited, patterned, A control gate electrode 3 is formed on the active region.
- thermal oxidation is performed to deposit silicon nitride and silicon oxide and cover the entire surface with a protective insulating film 16.
- Polysilicon and silicon oxide are deposited and anisotropically etched to form a sidewall including the sidewall silicon film 9 on the side surface of the control gate electrode 3, and ions are formed using the control gate electrode and the sidewall as a mask.
- Implantation is performed to form an n-type diffusion layer 2 that becomes a source / drain region [FIG. 29A].
- the sidewall silicon film other than the region where the drain contact hole is opened is removed by etching.
- the silicon oxide is deposited to form the first interlayer insulating film 8a, and the first interlayer insulating film 8a and the sidewall are selectively etched away by photolithography to form a sidewall on the drain region.
- a contact hole that exposes the side surface of the silicon film 9 is opened.
- polysilicon and silicon oxide are deposited and anisotropically etched to form the floating gate 5 including the sidewall silicon film 9 as a part [FIG. 29B].
- a polyimide film is formed by spin coating or the like, and CMP is performed to form an organic filler 22 embedded in the contact hole. Then, oxygen ions are implanted to convert the upper part of the floating gate into a silicon oxide film 18 [FIG. 29C].
- anisotropic etching is performed to remove a part of the protective insulating film 16 to expose the drain region. Then, after performing surface treatment such as cleaning and dilute hydrofluoric acid treatment, an n-type polysilicon film is deposited, and the n-type polysilicon film is patterned by a photolithography method. Lead wire 4 is formed [Fig. 29D].
- an insulating film such as a silicon oxide film is deposited to form a second interlayer insulating film 8b.
- the second interlayer insulating film 8b is selectively formed. Etching is performed to open a contact hole on the source region. After depositing TiN and Ti by sputtering, W is deposited to fill the contact hole, and etch back (or CMP) is performed to form the source lead 7 [FIG. 29E]. Thereafter, a metal film such as A1 is deposited by sputtering and patterned to form the metal wiring 20, and further an insulating film is deposited on the entire surface to form the third interlayer insulating film 8c [FIG. 29F].
- the organic filler is formed from polyimide, and a suitable resin material can be used instead of this material. However, it is desirable that it is a solvent-soluble material.
- the polysilicon film and the silicon oxide film are combined together. Etching or etching may be performed for each film.
- FIG. 30A to 30F are cross-sectional views in order of steps for explaining the fifth embodiment of the manufacturing method.
- an element isolation region 10 for partitioning an active region is formed, a gate insulating film is formed by thermal oxidation, and polysilicon and a silicon oxide film 23 are deposited.
- patterning is performed using a photolithography method, and the control gate electrode 3 is formed on the active region and the write / erase control wiring 11 is formed on the element isolation region 10.
- ion implantation is performed using the control gate electrode and the silicon oxide film 23 as a mask to form the n-type diffusion layer 2 to be a source / drain region [FIG. 30A].
- a polyimide film is formed by a spin coating method, etc., flattened by CMP, and then patterned by using a photolithography method to leave only on the drain region, and the first organic filler 22a Is formed.
- silicon oxide is deposited and planarized by CMP to form the first interlayer insulating film 8a [FIG. 30B].
- the second organic filler 22b is removed using a solvent, surface treatment is performed, an n-type polysilicon film is deposited, the n-type polysilicon film is patterned by a photolithography method, and a drain is extracted. Form line 4.
- an insulating film such as a silicon oxide film is deposited to form the second interlayer insulating film 8b.
- the drain lead is queried by etching or CMP, the second interlayer insulating film 8b is selected.
- the contact hole is opened on the source region by etching away.
- W is deposited to fill the contact hole, and etch back (or CMP) is performed to form the source lead 7 [FIG. 30E].
- a metal film such as A1 is deposited by sputtering and patterned to form the metal wiring 20, and further an insulating film is deposited on the entire surface to form the third interlayer insulating film 8c [FIG. 30F].
- the first organic filler is formed using polyimide.
- the first organic filler itself may be formed using a photosensitive resin.
- the filler can be directly formed by developing a photosensitive resin.
- the force used to ionize the floating gate partially in the previous example and the present example is formed using a heat-resistant high-temperature material such as an inorganic material. In this case, thermal oxidation can be used.
- both films can be deposited and anisotropic etching can be performed collectively. Etching can also be performed.
- the oxide film may be formed on the surface of the floating gate by the hot acid without depositing the silicon oxide film.
- FIG. 31A to 31C are cross-sectional views in order of steps for explaining the sixth embodiment of the manufacturing method.
- the process of Embodiment 5 of the manufacturing method is modified so that the source / drain regions are formed after the side walls are formed on the side surfaces of the gate.
- silicon oxide is formed.
- sidewalls are formed on the side surfaces of the control gate electrode 3 and the write / erase control wiring 11 by ion deposition and anisotropic etching, and ion implantation is performed to form the n-type diffusion layer 2 serving as the source and drain regions. .
- the first organic filler 22a and the first interlayer insulating film 8a are formed using the same method as in the previous embodiment [FIG. 31A].
- the floating gate 5 is formed by depositing polysilicon and silicon oxide and performing anisotropic etching [FIG. 31B]. Thereafter, using the same method as in the previous embodiment, processing is performed as shown in FIG. 31C.
- FIG. 32 is a sectional view for explaining Example 7 of the manufacturing method.
- the polysilicon floating gate formed in Embodiment 6 of the manufacturing method is changed to include an electron trap film. That is, after processing into the state shown in FIG. 31A, the first organic filler 22a is removed, and acid-aluminum and acid-silicon are deposited, and anisotropic etching is performed to form the insulator floating gate 5A. . Thereafter, the process after the process of forming the drain lead line 4 is performed and processed as shown in FIG.
- the second organic filler forming step and the floating gate acidifying step can be omitted, and the process is simplified.
- the force shown in the method using the organic filler for example, a material capable of highly selective etching with respect to silicon oxide such as silicon nitride or Si, is used as an inorganic filler. It may be used as one.
- the inorganic filler is not limited to silicon nitride, but may be formed of a phosphorus-containing oxide film or the like and removed using a technique such as highly selective vapor phase HF etching.
- 33A to 33D are cross-sectional views in order of the steps for explaining the eighth embodiment of the manufacturing method.
- a gate insulating film is formed by thermal oxidation, polysilicon is deposited, and patterning is performed.
- ion implantation is performed to form the n-type diffusion layer 2 serving as the source and drain regions.
- oxidized silicon Con is deposited to form a first interlayer insulating film 8a.
- polysilicon is deposited and patterned to form the floating gate 5.
- silicon oxide is further deposited to form a second interlayer insulating film 8b [FIG. 33A].
- the second interlayer insulating film 8b, the floating gate 5 and the first interlayer insulating film 8a are selectively removed by photolithography, and a contact hole is opened on the drain region [FIG. 33B]. .
- thermal oxidation is performed to form a silicon oxide film 25 as a gate insulating film on the inner surface of the floating gate 5 [FIG. 33C].
- the silicon oxide film on the bottom surface of the contact hole is removed by anisotropic etching, surface treatment is performed, and then an n-type single crystal silicon film 4d is grown in the contact hole by a selective growth method.
- insulating film 4c in the contact hole.
- polysilicon is deposited and etched back (or CMP) to embed the n-type polysilicon film 4a.
- the n-type single crystal silicon film 4d, the insulating film 4c, and the n-type polysilicon film 4a are formed. Drain leader 4 is formed.
- the second and first interlayer insulating films 8b and 8a are selectively removed by etching to form contact holes on the source regions.
- metal is deposited to fill the contact hole, and etch back (or CMP) is performed to form the source lead line 7 [FIG. 33D]. Further, if necessary, one or more layers of wirings and interlayer insulating films are formed.
- 34A to 34F are cross-sectional views in order of the steps for explaining the ninth embodiment of the manufacturing method.
- an element isolation region 10 for partitioning an active region is formed in the surface region of the p-type silicon substrate 1
- a gate insulating film is formed by thermal oxidation, polysilicon and titanium are deposited, and photolithography is performed.
- the control gate electrode 3 composed of the polysilicon film 3a and the metal film 3b is formed on the active region by patterning using the method.
- silicon oxide is deposited and anisotropic etching is performed to form a sidewall on the side surface of the control gate electrode 3, and ion implantation is performed using the control gate electrode and the side wall as a mask to form a source / drain.
- the n-type diffusion layer 2 to be a region is formed [FIG. 34A].
- thermal oxidation and silicon oxide deposition are performed to form a silicon oxide film 26, followed by polysilicon deposition and patterning, and a floating gate partially overlapping the control gate electrode 3.
- silicon oxide is deposited and flattened.
- the first interlayer insulating film 8a is formed by carrying out tanning [Fig. 34B].
- the first interlayer insulating film 8a and the floating gate 5 are selectively etched away by photolithography, and a contact hole is opened on the drain region.
- a silicon oxide film 25 is formed on the side surface [FIG. 34C].
- silicon is grown by selective growth to form an n-type single crystal silicon film 4d in the contact hole [FIG. 34D].
- polysilicon is deposited and patterned to leave the n-type polysilicon film 4a and form the drain lead line 4 composed of the n-type single crystal silicon film 4d and the n-type polysilicon film 4a.
- an insulating film such as a silicon oxide film is deposited to form a second interlayer insulating film 8b, and etch back (or CMP) is performed to expose the surface of the n-type polysilicon film 4a [FIG. 34E]. .
- the second interlayer insulating film 8b and the first interlayer insulating film 8a are selectively removed by etching to open a contact hole on the source region.
- metal is deposited by sputtering to fill the contact hole, and etch back (or CMP) is performed to form the source lead line 7.
- a metal film such as A1 is deposited by sputtering and patterned to form the metal wiring 20, and further an insulating film is deposited on the entire surface to form the third interlayer insulating film 8c [FIG. 34F].
- 35A to 35D are cross-sectional views in order of the steps for explaining the embodiment 10 of the manufacturing method.
- an element isolation region 10 for partitioning an active region is formed in the surface region of the p-type silicon substrate 1
- a resist film having an opening on the drain formation region is formed by photolithography, and ion implantation is performed using this as a mask.
- N-type diffusion layer 2 to be a drain region is formed by performing thermal oxidation to form a gate insulating film, and then depositing polysilicon and patterning by photolithography to form a control gate electrode 3 .
- a silicon oxide film 26 is formed by performing surface treatment, thermal oxidation, and silicon oxide film deposition, followed by polysilicon deposition and patterning, so that an overlapping portion with the control gate electrode 3 is formed. And the floating gate 5 extending on the drain region is formed [FIG. 35A].
- silicon oxide is deposited and anisotropic etching is performed to form sidewalls on the side surfaces of the control gate electrode 3, and ion implantation is performed. As a result, an n-type diffusion layer 2 to be a source region is formed.
- silicon oxide is deposited and flattened to form the first interlayer insulating film 8a [FIG. 35B].
- the first interlayer insulating film 8a and the floating gate 5 are selectively etched away by photolithography, a contact hole is opened on the drain region, and then thermal oxidation is performed.
- a silicon oxide film 25 serving as a gate insulating film is formed on the side surface.
- polysilicon is deposited and etched back (or CMP) is performed to form a drain lead 4 with n-type polysilicon force in the contact hole [Fig. 35C].
- the first interlayer insulating film 8a is selectively removed by etching, a contact hole is opened on the source region, a metal is deposited by sputtering to fill the contact hole, and etch back (or CMP) is performed to form the source. Leader line 7 is formed. Thereafter, a metal film such as A1 is deposited by sputtering and patterned to form the metal wiring 20, and further an insulating film is deposited on the entire surface to form the second interlayer insulating film 8b [FIG. 35D].
- FIG. 36A to FIG. 36D are cross-sectional views in order of the steps for explaining Example 11 of the manufacturing method.
- an element isolation region 10 for partitioning an active region is formed in the surface region of the p-type silicon substrate 1
- a resist film having an opening on the drain formation region is formed by photolithography, and ion implantation is performed using this as a mask.
- the n-type diffusion layer 2 to be the drain region is formed.
- polysilicon is deposited and patterned by photolithography to form the floating gate 5 covering the drain region.
- surface treatment and thermal oxidation are performed to form a gate insulating film, followed by deposition of polysilicon and patterning to form the control gate electrode 3 having an overlapping portion with the floating gate 5 [Fig.
- silicon oxide is deposited and anisotropic etching is performed to form sidewalls on the side surfaces of the control gate electrode 3, and ion implantation is performed to form the n-type diffusion layer 2 serving as a source region. Subsequently, silicon oxide is deposited and flattened to form a first interlayer insulating film 8a [FIG. 36B].
- the first interlayer insulating film 8a and the floating gate 5 are selectively etched away by photolithography, and a contact hole is opened on the drain region, followed by thermal oxidation.
- a silicon oxide film 25 serving as a gate insulating film is formed on the inner surface of the floating gate 5.
- polysilicon is deposited and etched back (or CMP) is performed to form a drain lead 4 with n-type polysilicon force in the contact hole [Fig. 36C].
- the first interlayer insulating film 8a is selectively removed by etching, a contact hole is opened on the source region, a metal is deposited by sputtering to fill the contact hole, and etch back (or CMP) is performed to form the source. Leader line 7 is formed. Thereafter, a metal film such as A1 is deposited by sputtering and patterned to form the metal wiring 20, and further an insulating film is deposited on the entire surface to form the second interlayer insulating film 8b [FIG. 36D].
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Cited By (3)
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---|---|---|---|---|
KR20140081398A (ko) * | 2012-12-21 | 2014-07-01 | 에스케이하이닉스 주식회사 | 비휘발성 메모리 장치 및 그 제조방법 |
TWI800228B (zh) * | 2021-02-25 | 2023-04-21 | 新加坡商新加坡優尼山帝斯電子私人有限公司 | 使用半導體元件的記憶裝置 |
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Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8097912B2 (en) * | 2007-06-13 | 2012-01-17 | Macronix International Co. Ltd. | Systems and methods for self convergence during erase of a non-volatile memory device |
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JP2010182752A (ja) * | 2009-02-03 | 2010-08-19 | Renesas Electronics Corp | 不揮発性半導体記憶装置及びその製造方法 |
TWI419166B (zh) * | 2010-01-08 | 2013-12-11 | Yield Microelectronics Corp | Low - pressure rapid erasure of nonvolatile memory |
JP5378255B2 (ja) * | 2010-02-02 | 2013-12-25 | 株式会社東芝 | 不揮発性半導体記憶装置および不揮発性半導体記憶装置の駆動方法 |
US9224746B2 (en) * | 2013-05-21 | 2015-12-29 | Sandisk Technologies Inc. | Inverted-T word line and formation for non-volatile storage |
KR102109462B1 (ko) * | 2013-06-13 | 2020-05-12 | 에스케이하이닉스 주식회사 | 비휘발성 메모리 장치 및 그 제조방법 |
US9691776B2 (en) | 2013-06-13 | 2017-06-27 | SK Hynix Inc. | Nonvolatile memory device |
DE102014114197B4 (de) * | 2014-09-30 | 2016-11-17 | Infineon Technologies Ag | Chip und Verfahren zum Identifizieren eines Chips |
KR102300122B1 (ko) * | 2015-02-17 | 2021-09-09 | 에스케이하이닉스 주식회사 | 전하 트랩 불휘발성 메모리소자 및 그 제조방법과, 전하 트랩 불휘발성 메모리소자의 동작방법 |
JP6581446B2 (ja) * | 2015-09-09 | 2019-09-25 | 東芝メモリ株式会社 | 絶縁膜及び記憶装置 |
JP2018147541A (ja) | 2017-03-08 | 2018-09-20 | 株式会社東芝 | メモリを備えた集積回路および書き込み方法 |
US11751386B2 (en) * | 2021-08-11 | 2023-09-05 | Micron Technology, Inc. | Field-effect transistors, devices containing such field-effect transistors and methods of their formation |
CN118044350A (zh) * | 2021-12-10 | 2024-05-14 | 铠侠股份有限公司 | 存储器件 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01191480A (ja) * | 1988-01-27 | 1989-08-01 | Toshiba Corp | 不揮発性メモリセル |
JPH05251710A (ja) * | 1991-10-22 | 1993-09-28 | Oki Electric Ind Co Ltd | Mos型半導体記憶装置 |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5598367A (en) * | 1995-06-07 | 1997-01-28 | International Business Machines Corporation | Trench EPROM |
US6897520B2 (en) * | 1996-05-29 | 2005-05-24 | Madhukar B. Vora | Vertically integrated flash EEPROM for greater density and lower cost |
KR100358062B1 (ko) * | 1998-12-30 | 2003-01-24 | 주식회사 하이닉스반도체 | 플래쉬메모리셀및그의제조방법 |
JP2005012137A (ja) * | 2003-06-23 | 2005-01-13 | National Institute Of Advanced Industrial & Technology | 二重ゲート型不揮発性メモリ素子 |
JP4427431B2 (ja) * | 2004-11-05 | 2010-03-10 | シャープ株式会社 | 半導体記憶装置、半導体記憶装置の製造方法および半導体記憶装置の動作方法 |
-
2005
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Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01191480A (ja) * | 1988-01-27 | 1989-08-01 | Toshiba Corp | 不揮発性メモリセル |
JPH05251710A (ja) * | 1991-10-22 | 1993-09-28 | Oki Electric Ind Co Ltd | Mos型半導体記憶装置 |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20140081398A (ko) * | 2012-12-21 | 2014-07-01 | 에스케이하이닉스 주식회사 | 비휘발성 메모리 장치 및 그 제조방법 |
KR101978450B1 (ko) | 2012-12-21 | 2019-05-14 | 에스케이하이닉스 주식회사 | 비휘발성 메모리 장치 및 그 제조방법 |
TWI807584B (zh) * | 2021-02-02 | 2023-07-01 | 新加坡商新加坡優尼山帝斯電子私人有限公司 | 半導體元件記憶單元及半導體元件記憶裝置 |
TWI800228B (zh) * | 2021-02-25 | 2023-04-21 | 新加坡商新加坡優尼山帝斯電子私人有限公司 | 使用半導體元件的記憶裝置 |
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JP5045105B2 (ja) | 2012-10-10 |
US7880215B2 (en) | 2011-02-01 |
US20080144377A1 (en) | 2008-06-19 |
JPWO2006054605A1 (ja) | 2008-05-29 |
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