WO2015140946A1 - 半導体記憶装置 - Google Patents
半導体記憶装置 Download PDFInfo
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- WO2015140946A1 WO2015140946A1 PCT/JP2014/057438 JP2014057438W WO2015140946A1 WO 2015140946 A1 WO2015140946 A1 WO 2015140946A1 JP 2014057438 W JP2014057438 W JP 2014057438W WO 2015140946 A1 WO2015140946 A1 WO 2015140946A1
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- G—PHYSICS
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- G11C13/00—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00
- G11C13/0002—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using resistive RAM [RRAM] elements
- G11C13/0021—Auxiliary circuits
- G11C13/0069—Writing or programming circuits or methods
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C11/00—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor
- G11C11/02—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements
- G11C11/16—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using elements in which the storage effect is based on magnetic spin effect
- G11C11/165—Auxiliary circuits
- G11C11/1659—Cell access
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C11/00—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor
- G11C11/02—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements
- G11C11/16—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using elements in which the storage effect is based on magnetic spin effect
- G11C11/165—Auxiliary circuits
- G11C11/1675—Writing or programming circuits or methods
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C13/00—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00
- G11C13/0002—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using resistive RAM [RRAM] elements
- G11C13/0004—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using resistive RAM [RRAM] elements comprising amorphous/crystalline phase transition cells
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C13/00—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00
- G11C13/0002—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using resistive RAM [RRAM] elements
- G11C13/0021—Auxiliary circuits
- G11C13/003—Cell access
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C13/00—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00
- G11C13/0002—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using resistive RAM [RRAM] elements
- G11C13/0007—Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00 using resistive RAM [RRAM] elements comprising metal oxide memory material, e.g. perovskites
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C2213/00—Indexing scheme relating to G11C13/00 for features not covered by this group
- G11C2213/70—Resistive array aspects
- G11C2213/71—Three dimensional array
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C2213/00—Indexing scheme relating to G11C13/00 for features not covered by this group
- G11C2213/70—Resistive array aspects
- G11C2213/72—Array wherein the access device being a diode
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C2213/00—Indexing scheme relating to G11C13/00 for features not covered by this group
- G11C2213/70—Resistive array aspects
- G11C2213/74—Array wherein each memory cell has more than one access device
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C2213/00—Indexing scheme relating to G11C13/00 for features not covered by this group
- G11C2213/70—Resistive array aspects
- G11C2213/75—Array having a NAND structure comprising, for example, memory cells in series or memory elements in series, a memory element being a memory cell in parallel with an access transistor
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C2213/00—Indexing scheme relating to G11C13/00 for features not covered by this group
- G11C2213/70—Resistive array aspects
- G11C2213/79—Array wherein the access device being a transistor
Definitions
- the present invention relates to a technology effective when applied to a rewritable nonvolatile memory, for example, a semiconductor memory device having a phase change memory, ReRAM, or STT-MRAM, or a storage system including the semiconductor memory device.
- a rewritable nonvolatile memory for example, a semiconductor memory device having a phase change memory, ReRAM, or STT-MRAM, or a storage system including the semiconductor memory device.
- Patent Document 1 a technique for manufacturing a large-capacity semiconductor memory device by using a phase change memory as a nonvolatile memory and connecting a plurality of bits in series in a chain shape is known (for example, Patent Document 1). See).
- This publication states that “in a semiconductor memory in which a diode and a transistor are connected in series, there is a problem that the characteristics of the transistor deteriorate due to carriers entering the transistor from the diode” (see summary).
- paragraph [0044] states that, for example, the following operation is performed in a cell in which a memory cell in which a transistor and a phase change element are connected in parallel is connected in series, that is, a chain cell. Has been.
- Patent Document 2 This publication states that “a memory cell MC is composed of a chalcogenide wiring GST, a resistance wiring connected to each of both ends, and a cell transistor in which the other end of each of the resistance wirings is connected to a source and a drain. A plurality of cells connected in series, one end connected to the source, a drain connected to the bit line, the other end of the plurality connected in series to the source line, and the gate of the memory cell connected to the word line Then, a cell string is formed by connecting the gate of the selection transistor to a block selection line, and a plurality of the cell strings are provided to form a memory cell array. (See summary). Further, as an explanation of FIG. 6, “FIGS. 5 and 6 show other examples of read and write operations.
- Patent Document 3 This publication states that “a resistance change element 309 including a resistance change layer 309b that reversibly changes based on electric signals having different polarities applied between the lower electrode 309a and the upper electrode 309c, and a transistor 317, Are connected in series, the resistance change layer 309b is made of an oxygen-deficient transition metal oxide layer, and the lower electrode 309a and the upper electrode 309c are made of materials made of different elements.
- the standard electrode potential V1 of the electrode 309a, the standard electrode potential V2 of the upper electrode 309c, and the standard electrode potential Vt of the transition metal satisfy the relationship of Vt ⁇ V2 and V1 ⁇ V2.
- the read voltage is applied so that the upper electrode 309c becomes positive with respect to the lower electrode 309a "(summary). Irradiation).
- a part of the structure of the memory array has a memory element and a selection element connected in parallel.
- the memory cells are connected in series to form a chain structure (memory chain).
- the gate electrode of the selection element is shared among a plurality of memory chains and is electrically connected to each other. The following description will be made assuming that the selection element is a transistor.
- Transistors and nonvolatile memories are connected in parallel, and a plurality of sets are connected in series.
- One of the memory chains MU is connected to the source electrode without going through the selection element, and the other is connected to the bit line through the selection element XTr.
- the gate electrodes of the zeroth-layer Z selection transistors are connected to each other between the memory chains MU and controlled to the potential VZ0. The same applies to the Z selection transistors of the first to seventh layers.
- FIG. 5 shows the potential of each electrode when writing, that is, rewriting the values of “0” and “1” of the nonvolatile memory.
- the selected bit is the phase change element PCM1 in the memory chain MU00.
- PCM0 and PCM2-7 are non-selected bits.
- the phase change elements in the memory chains MU01, 10 and 11 are set as non-selected bits. Since the source electrode is connected to the memory chain MU without going through the selection element, when the potential VS is changed, the phase change element PCM in the memory chain MU is disturbed, so that the potential VS of the source electrode is kept constant. That is, it is desirable to maintain at 0V. In order to pass a write current, for example 40 ⁇ A, to the phase change element PCM, the potential VBL-S of the bit line connected to the memory chain is changed from 0V to, for example, 7V.
- the drain voltage of the selection element XTr becomes 7V.
- the drain-source voltage of the on-state MOS is 0.5V
- the gate-source voltage is 5V
- the gate-source voltage of the off-state MOS is 0V
- the write voltage of the phase change element is 3V.
- the source voltage of the selection element XTr is 6.5V
- the gate voltage is 11.5V.
- the drain voltage of the seventh layer Z selection transistor ZTr7 of the selected memory chain MU00 is 6.5V
- the source voltage is 6V
- the gate voltage is 11V.
- the gate electrode of the seventh layer Z selection transistor of the selected memory chain MU00 is connected to the gate electrode of the seventh layer Z selection transistor of the unselected memory chain MU11. Therefore, the gate voltage of the Z selection transistor in the seventh layer of the unselected memory chain MU11 is 11V.
- the source electrode of the Z selection transistor of the unselected memory chain MU11 is connected to the source line via the 0th to 6th phase change elements PCM, the potential becomes equal to the source potential VS, and 0V become. Therefore, paying attention to the transistor of the unselected chain MU11, the gate-source voltage is as high as 11V.
- the MOS may fail due to gate breakdown caused by application of a high voltage between the gate and the source. That is, there is a problem that the reliability of the semiconductor memory device 601 is lowered.
- the present invention includes a plurality of means for solving the above-described problems.
- the present invention includes: “a plurality of memory chains including a plurality of memory cells connected in series, wherein the memory cell includes a cell transistor;
- the memory chain has a structure in which the memory elements are connected in parallel, and a power supply voltage and a ground voltage are supplied from the outside, and a voltage used for rewriting the memory elements.
- the semiconductor memory device is characterized in that is lower than the ground voltage.
- a highly reliable semiconductor memory device can be realized.
- 1 is an example showing a circuit configuration of a part of a memory array of a semiconductor memory device according to Embodiment 1 of the present invention
- 4 is an example showing a write operation of a part of the memory array of the semiconductor memory device according to the first embodiment of the present invention.
- 4 is an example showing an operation of a part of the memory array of the semiconductor memory device according to the first embodiment of the present invention. It is an example which shows the circuit structure of a part of memory array. It is an example which shows the write operation of a part of memory array.
- It is an example of the block diagram of the semiconductor memory device of Example 1 of this invention. It is an example of the block diagram of the power supply circuit of the semiconductor memory device of Example 1 of this invention.
- circuit diagram of the signal voltage converter circuit of the semiconductor memory device of Example 1 of this invention It is an example of the block diagram of the signal voltage converter circuit of the semiconductor memory device of Example 1 of this invention.
- 1 is an example showing a cross-sectional view of a part of a memory array of a semiconductor memory device according to Embodiment 1 of the present invention; It is an example which shows the plane projection figure of a part of memory array of the semiconductor memory device of Example 1 of this invention. It is an example which shows the circuit structure of a part of memory array of the semiconductor memory device of Example 2 of this invention. It is an example which shows the operation
- FIG. 1 is an example of a circuit configuration of a part of the memory array 602 of the semiconductor memory device 601 of this embodiment.
- the memory array 602 is composed of a plurality of memory chains MU.
- the memory chain includes a selection element XTr, a plurality of phase change elements PCM, and a plurality of Z selection elements ZTr.
- One phase change element PCM and one Z selection element ZTr are connected in parallel to constitute a memory cell.
- a plurality of the memory cells are connected in series.
- one phase change element PCM and a plurality of Z selection elements ZTr are connected in parallel.
- a plurality of phase change elements PCM and one Z selection element ZTr can be connected in parallel, or a plurality of phase change elements PCM and a plurality of Z selection elements ZTr can be connected in parallel. Needless to say.
- the Z direction is a direction orthogonal to the silicon substrate, and the X direction and the Y direction are preferably orthogonal to the Z direction and orthogonal to each other. In this way, a plurality of memory cells existing in the Z direction can be collectively formed by a single drilling process, and the manufacturing cost can be reduced.
- the gate electrodes of the Z selection element ZTr are connected to each other among the plurality of memory chains MU.
- the potential of the gate electrode of the 0th layer Z selection transistor ZTr0 is the same potential in any memory chain MU. It has become. With such a configuration, there is an effect that the chip area of the semiconductor memory device 601 can be reduced by reducing the wiring area of the gate electrode of the Z selection transistor, and an inexpensive semiconductor memory device 601 can be provided.
- the gate electrode of the Z selection transistor can be separated for each bit line and the potential can be individually controlled.
- the gate electrode of the Z selection transistor can be separated for each X selection line and the potential can be individually controlled. In this case, since the optimum gate potential of the Z selection transistor ZTr can be controlled for each location, the gate breakdown voltage of the Z selection transistor ZTr can be reduced, and the reliability of the semiconductor memory device 601 can be improved.
- a vertical type GAA-NMOSFET Gate All Around n-channel MOSFET
- NMOSFET Gate All Around n-channel MOSFET
- the number of phase change elements PCM included in the memory chain MU can be increased, and a large-capacity semiconductor memory device 601 can be realized.
- PMOS can be used.
- the vertical MOSFET the size of the transistor can be reduced as compared with the case of using a planar MOS with 4F2 (F is the minimum processing dimension), and thus the capacity can be increased.
- the GAA structure By using the GAA structure, it becomes possible to widen the gate width compared to the case of using a planar MOS, improving the driving power of the MOS, increasing the number of memory cells included in the phase change chain MU, The capacity can be increased.
- the voltage applied to the gate electrode of the non-selected Z selection transistor can be made lower than when the NMOS is used. Therefore, the gate breakdown voltage of the Z selection MOS can be reduced, and the reliability of the semiconductor memory device 601 can be reduced. Has the effect of improving.
- a chalcogenide material particularly a GeSbTe alloy (germanium-antimony-tellurium alloy) can be used.
- the chalcogenide material can take two metastable states, an amorphous state (amorphous state) and a crystalline state, and the electric resistance value in each state is different. That is, the resistance is high in the case of amorphous and low resistance in the crystalline state.
- the values “0” and “1” can be stored.
- the amorphous case is ‘0’ and the crystalline state is ‘1’.
- Rewriting from '0' to '1' is erasing, and rewriting from '1' to '0' is writing.
- Rewriting is performed by causing a current to flow through the phase change element PCM and generating Joule heat.
- the phase change element is crystallized by holding at a temperature equal to or higher than the crystallization temperature for a certain time.
- it is made amorphous (vitrified) by heating above the melting point and rapidly cooling.
- the phase change element PCM can take a value of three or more.
- the phase change element is described by taking a crystal-amorphous phase change as an example.
- a crystal A-crystal B phase change can be used.
- the crystal A and the crystal B are crystals having different crystal structures.
- the case where a phase change element is used as a memory element will be described as an example.
- ReRAM or STT-MRAM spin injection MRAM
- STT-MRAM spin injection MRAM
- the semiconductor memory device 601 having a high write data rate can be realized by using the STT-MRAM having a high rewrite speed.
- a phase change element is used as a memory element.
- Write and erase are performed by generating Joule heat by supplying a write current to the phase change element PCM.
- the write current is 40 ⁇ A, for example, and the erase current is 20 ⁇ A, for example. Note that it is logically possible to perform writing or erasing by generating Joule heat by passing a current through an adjacent Z selection MOS.
- a read voltage is applied to the phase change element PCM, and then a voltage change of the bit line due to a current flowing through the source electrode through the phase change element PCM is amplified by a sense amplifier to determine “0” and “1” To do.
- a double gate NMOSFET as the X selection element XTr.
- the gate width of the MOSFET can be increased compared to the case of using a planar MOSFET, so that it is easy to secure a current necessary for writing the phase change element PCM. Become. Therefore, there is an advantage that the yield of the semiconductor memory device 601 can be improved. Further, since the driving power of the MOSFET is improved, the number of memory cells included in the memory chain can be increased.
- the double gate NMOSFET has two gate electrodes, and when an on voltage is applied to both gate electrodes, the MOS is turned on (becomes a low resistance state). When an on voltage is applied only to one of the gate electrodes, or when an off voltage is applied to all the gate electrodes, the MOS is turned off (becomes a high resistance state). In the following description, it is assumed that a double gate NMOSFET is used.
- the selected chain is MU00 and PCM1 is written as an example.
- a negative voltage for example -7V
- the voltage is defined as a ground potential of 0V.
- the ground potential VSS can be supplied from the outside of the semiconductor memory device 601.
- the power supply voltage VDD is also supplied from the outside of the semiconductor memory device 601.
- the potential of the selected bit line VBL-S is compared with the potential of the write driver that drives the selected bit line VBL-S. Due to the voltage drop in the wiring and access transistor from the write driver to the selected bit line VBL-S, the potential of the write driver is reduced. Needless to say, it is slightly higher than The voltage of the write driver is, for example, -7.5V.
- the drain-source voltage of the on-state MOS is 0.5V
- the gate-source voltage is 5V
- the gate-source voltage of the off-state MOS is 0V
- the X of the selection chain MU00 will be described. Focusing on the selection transistor XTr, in order to set the source voltage to ⁇ 7 V and the gate-source voltage to 5 V, the two gate voltages of the X selection transistor may be set to ⁇ 2 V, respectively.
- the drain voltage of the X selection transistor XTr is ⁇ 6.5 V because the drain-source voltage of the MOS in the on state is 0.5 V and the source voltage is ⁇ 7 V.
- At least one gate voltage of the X selection transistor may be set to ⁇ 7V.
- the X selection potential VX2 is controlled to -7V.
- the gate voltage of the Z selection transistor ZTr7 of the selection chain MU00 may be ⁇ 1.5V in order to set the source voltage to ⁇ 6.5V and the gate-source voltage to 5V.
- the gate voltages of ZTr6, 5, 4, 3, and 2 may be set to ⁇ 1V, ⁇ 0.5V, 0V, 0.5V, and 1V, respectively.
- the gate voltage may be set to ⁇ 3.5V in order to turn it off.
- the drain voltage of the Z selection transistor ZTr1 becomes ⁇ 0.5V.
- the gate voltage may be 4.5V.
- a write current for example, 40 ⁇ A flows through the selected chain MU00 from time t1 to time t2.
- the potential VS of the source electrode is approximately 0V. Strictly speaking, it goes without saying that the potential of the source electrode is slightly higher than 0 V, which is the potential of the GND terminal, due to a voltage drop due to the current flowing from the source electrode to the GND terminal.
- the gate-source voltage is 5 V or less in all Z selection transistors ZTr including the selected chain and the non-selected chain. That is, it can be seen that the use of a negative voltage as the voltage applied to the selected bit line solves the problem that the gate-source voltage of the Z selection transistor ZTr described in the problem becomes as high as 11 V, for example.
- phase change element, ReRAM, and STT-MRAM are two-terminal current rewritable nonvolatile memory elements, and are rewritten by flowing a current from one side of the memory element to the other end. At this time, a constant write current I is required for rewriting. Further, the memory element has a constant dynamic resistance R. Dynamic resistance is the resistance of the memory element being rewritten. At this time, the voltage drop amount V can be obtained from the following equation (1) of Ohm's law.
- V RI (1) Since the voltage drop amount V is so large that it cannot be ignored with respect to the write voltage, for example, 7.5 V, it is necessary to consider the voltage drop in the memory element in the operation of the semiconductor memory device 601. Strictly speaking, since a slight off-current also flows through the Z selection transistor, the exact voltage drop amount is slightly different from that of the equation (1).
- the memory cells are connected in series, and in the non-selected memory cells in the selected memory chain, most of the current flows through the Z selection transistor.
- the voltage drop amount in the unselected memory cell can be obtained from the product of the resistance between the source and drain of the Z selection transistor and the write current. Strictly speaking, it goes without saying that a small amount of current flows through the phase change element of the non-selected memory cell.
- the write current I can be extremely reduced. Problems caused by descent are unlikely to occur.
- the potential of the source potential VS is always maintained at 0 V, an array configuration with a large parasitic capacitance of the source line is possible, and the number of memory chains MU connected to the source line can be increased. Since the area of the array 602 can be reduced, a semiconductor memory device 601 with low manufacturing cost can be realized. Further, in a structure having no selection transistor between the memory cell and the source line, when the voltage of the source line varies, the voltage of the memory cell also varies, so that a disturb current flows to the phase change element PCM. This adversely affects operational reliability. In the present system in which the source line potential is kept constant, this problem does not occur.
- Fig. 3 shows a configuration in which the voltage level used is reduced. By reducing the area, the area of the power supply circuit can be reduced, and the semiconductor memory device 601 with low manufacturing cost can be realized.
- the gate-source breakdown voltage of the Z selection MOS is set to a breakdown voltage higher than 5 V in the example of FIG. 2, for example, 7.7 V. From time t2 to t3, a write current, for example, 40 ⁇ A flows. At this time, the Z selection potential VZ7 is set to 0V. In FIG. 2, VZ7 is ⁇ 1.5V, and the gate-source voltage is 5V. In FIG. 3, VZ7 is 0V, and the gate-source voltage is, for example, 6.5V. Since this voltage is lower than the withstand voltage 7.7V, there is no problem in the reliability of the MOS. In this way, it is not necessary to prepare a voltage of -1.5V, and the voltage level can be reduced.
- the current at the time of erasing is 35 ⁇ A, for example. It is desirable that the temperature of the phase change element heated by the Joule heat is lower than the temperature of the phase change element during writing. In this example, a current is passed between the source and drain of the Z selection transistor ZTr, and Joule heat is generated there (bundle erasure). That is, Joule heat is generated in the channel of the Z selection transistor, and this heat is transferred to the phase change element PCM to crystallize the phase change element PCM.
- the gate-source voltage of the Z selection transistor ZTr is 4.5V. It is desirable that the Z selection transistor ZTr is not completely turned on.
- the Z selection potential is controlled more finely for each layer than the write, and the gate voltage of the Z selection transistor is set using a potential of at least five levels or more. It is desirable to control. Compared with the case of FIG. 5, since the gate voltage is low, it is possible to control the gate voltage of five levels or more with power saving, and the power saving semiconductor memory device 601 can be realized.
- Bundle erasing can erase the phase change elements of multiple memory cells at once. It is desirable to erase the entire memory chain simultaneously. This is because if only a part of the memory chain is to be erased, the memory cells adjacent to the erase region are likely to be mistakenly erased. Furthermore, it is desirable to erase a plurality of memory chains at once. This makes it possible to heat adjacent memory chains using heat generated from one memory chain or reduce thermal escape, reduce electrical energy required for erasing, and enable erasing at high speed.
- the semiconductor memory device 601 can be realized. The reason why the heat escape can be reduced is that the memory chain adjacent to a certain memory chain is heated so that the temperature difference between the memory chains is reduced and the heat flux density is proportional to the temperature difference. This is because the heat flux between the chains is reduced.
- the selected bit line potential VBL-S at the time of erasing is a positive voltage.
- 2.7V the voltage to be applied can be supplied without using the booster circuit, and by eliminating power loss in the booster circuit, the number of memory chains that can be simultaneously erased can be increased to 512, for example. Thereby, the erasing speed can be improved to, for example, 400 MB / s.
- the selected bit line potential VBL-S at the time of reading is a positive voltage. For example, 1V.
- a positive voltage By using a positive voltage, it becomes possible to supply power without using a booster circuit, and lead power consumption can be reduced. Thereby, a semiconductor memory device 601 with low power consumption can be provided.
- bit line potential at the time of erasing or reading is as low as 2.7 V or 1.0 V, a high-speed semiconductor memory device 601 can be realized.
- FIG. 6 shows the configuration of the semiconductor memory device 601.
- the semiconductor memory device 601 is supplied with the power supply voltage VDD and the ground voltage VSS from the outside of the chip, and communicates with the control signal through the data signal line DQ.
- Input control signals include a chip valid signal CE, a command latch valid signal CLE, an address latch valid signal ALE, a clock signal CLK, a read / write valid signal W / R #, and a write protect signal WP #.
- There is a strobe DQS and an output control signal is a read busy signal R / B #.
- an I / O signal power supply VCCQ and an I / O signal ground source VSSQ can be supplied.
- the semiconductor memory device 601 includes a command decoder, a control circuit, a buffer device 606, a power supply circuit 605, a column system circuit 604, a row system circuit 603, and a memory array 602. Power is supplied from the power supply circuit to the column circuit 604, the row circuit 603, the command decoder, the control circuit, and the buffer device 606. A part of the voltage is boosted or stepped down, and the remaining voltage is supplied with VDD as it is.
- the voltage of the control signal from the command decoder, control circuit, and buffer device 606 to the row system circuit is preferably 2.3V.
- the power consumption of the semiconductor memory device 601 can be reduced by using a signal having a positive voltage and a small absolute value of the voltage compared to the X selection potential VX, for example, -7V in the example of FIG. .
- the row system circuit includes a signal voltage conversion circuit, that is, a level shifter, and converts the signal voltage level from 2.3V to ⁇ 7V in the level shifter.
- the voltage of the control signal from the command decoder, the control circuit, and the buffer device 606 to the column system circuit is preferably 2.3V.
- the power consumption of the semiconductor memory device 601 can be reduced by using a signal having a positive voltage and a small absolute value of the voltage compared to the selected bit line potential VBL, for example, -7 V in the example of FIG. it can.
- the column circuit does not include a signal voltage conversion circuit, that is, a level shifter, and a plurality of level shifters are arranged in the memory array 602 to convert the signal voltage level from 2.3V to ⁇ 7V.
- the column-related signal has a signal pulse width of, for example, 10 ns, which is shorter than the pulse width of the row-related signal, for example, 2 ⁇ s, the influence of this signal switching on the power consumption of the semiconductor memory device 601 is larger than that of the row-related circuit. . Therefore, the column circuit is driven by, for example, 2.3 V, the global bit line global BL is driven by 2.3 V, and among the plurality of level shifters in the memory array 602, a level shifter near the driven region is used. By converting the signal voltage, the semiconductor memory device 601 with low power consumption can be realized.
- the level shifter drives a plurality of bit lines BL. That is, it is desirable that the number of level shifters is larger than the total number of row-related circuits and column-related circuits.
- the power supply circuit consists of a booster circuit and a voltage regulator.
- As the booster circuit it is desirable to use the Discon type booster circuit shown in FIG.
- the voltage regulator generates an output voltage Voutput based on the reference voltage Vref and the control signal. This voltage is supplied to the column circuit.
- the output voltage Voutput is, for example, ⁇ 7, 5V.
- the selected bit line potential VBL-S becomes ⁇ 7 V because this voltage is affected by the voltage drop in the wiring and the access transistor from the write driver to the selected bit line VBL-S.
- level shifter circuit will be described with reference to FIGS.
- the level shifter circuit includes a differential amplifier circuit, a first stage amplifier circuit, and a second stage amplifier circuit.
- the high-voltage side H2.3V and low-voltage side L0V signals are converted into high-voltage side H2.3V and low-voltage side L-2.3V signals using a differential amplifier circuit.
- the signal is converted into a high voltage side H0V, a low voltage side L-4.2V, a high voltage side H0V, and a low voltage side L-7.5V.
- the power loss at the time of voltage conversion is reduced by adopting a two-stage voltage amplifier circuit.
- FIG. A circuit can be configured by using PMOSFET and NMOSFET.
- FIG. 11 A part of the structure of the plurality of memory chains MC will be described with reference to FIGS.
- four memory chains MC are arranged.
- the pitch (cycle) of the memory chain is 2F in both the X direction and the Y direction.
- a memory chain MC is arranged in the gap of the X selection line XSEL.
- FIG. 10 shows a cross section AB of FIG. A silicon oxide film 906, a gate oxide film 903, a silicon channel 904, a phase change material 905, a Z selection transistor gate electrode 901, an interlayer insulating film 902, and a memory chain MC are shown.
- FIG. 12 is an example of a configuration diagram illustrating the semiconductor memory device 601 according to the second embodiment.
- the selected bit line potential VBL-S at the time of writing is 0V, and the source potential VS is 7.5V.
- the source potential of the Z selection transistor in the non-selected memory chain rises, so that the gate-source breakdown voltage of the non-selected memory chain can be reduced.
- the memory cell is connected to the source line without going through the selection element. Therefore, the source electrodes of all Z selection transistors of the unselected chain MU are electrically connected to the source destination via the phase change element PCM. Therefore, at the time of writing, the source voltages of all the Z selection transistors in the unselected chain MU are 7.5V.
- the Z selection potential VZ is between 12V and 4V, the gate-source voltages of all the Z selection transistors in the unselected chain MU are ⁇ 3.5 to 4.5V. That is, it becomes smaller than 11V shown in FIG.
- the area of the power supply circuit can be reduced, and a low-cost semiconductor memory device can be provided. Further, since the source potential at the time of erasing or reading is as low as 2.7 V or 1.0 V, a high-speed semiconductor memory device 601 can be realized.
- FIG. 14 is an operation example of the semiconductor memory device 601 in the third embodiment. The description of the components having the same functions as those shown in FIG. 2 already described with reference to FIG. 2 is omitted.
- the selected bit line potential VBL-S at the time of writing is 0V, and the source potential VS is 7.5V.
- the source potential of the Z selection transistor in the non-selected memory chain rises, so that the gate-source breakdown voltage of the non-selected memory chain can be reduced.
- the source potential VS is maintained at 7.5 V during reading and erasing. Therefore, the disturb current does not flow through the phase change element PCM in the memory chain MU. Furthermore, since the source potential is kept constant, there is no need to reduce the parasitic capacitance of the source line.
- a voltage of 4.8 V is applied to the selected bit line, so that the potential difference between the selected bit line and the source line is set to 2.7 V.
- the following configuration is further essential. That is, the number of memory chains connected to the same source line is equal to or more than the number of gate electrodes of Z selection transistors connected to one electrode and controlled to the same potential. With this configuration, the area of the memory array 602 is reduced with a minimum control circuit, and the source voltage is lowered when a high voltage at the time of writing is applied to the gate electrode of the Z selection transistor. Therefore, the problem that a high voltage is applied between the gate and the source of the non-selected Z selection transistor does not occur.
- the memory array 602 preferably has a plurality of Z selection lines and a plurality of source lines, it is necessary to always control the potentials of the source lines and the Z selection lines in consideration of the gate breakdown voltage.
- the source line in the corresponding region has at least 6V or more. It is necessary to apply a voltage.
- FIG. 16 an example of a semiconductor memory device having a small number of process steps and a low manufacturing cost will be described with reference to FIG. For comparison, FIG. 16 is used.
- the potential VBL-S of the selected bit line is higher than the potential VS of the source line, and current flows from the selected bit line toward the source line.
- the potential VS of the source line is 0V.
- the gate voltage of the Z selection transistor is partly as high as 11 V as in FIG. 5, and the source voltage of the Z selection transistor in the unselected chain is 0 V, which causes a problem that the gate-source voltage increases.
- a negative voltage such as ⁇ 7 V is used as the voltage of the selected bit line.
- 15 and 16 differ in the polarity of the diode. By doing so, the gate-source voltage can be reduced to, for example, 5 V or less as in the first embodiment, and a highly reliable semiconductor memory device 601 can be realized.
- FIGS. 1 An example of a semiconductor memory device having a small chip area and a low manufacturing cost will be described with reference to FIGS.
- the description of the components having the same functions as those shown in FIG. 1 already described with reference to FIG. 1 is omitted.
- FIG. 17 shows Z selection MOS gate electrodes 4, 5, and 6 that are part of the memory array 602. 0V is applied to each electrode.
- Each of the Z selection MOS gate electrodes can be regarded as a parallel plate capacitor, and is electrically coupled to each other by electric capacity. Therefore, by changing the potential of some of the electrodes, the potential of other electrodes may change. By utilizing this, the voltage of the Z selection MOS gate electrode at the time of writing is controlled.
- the Z-selection MOS gate electrode 5 is disconnected from the ground voltage to be in a floating state.
- ⁇ 1V is supplied to the Z selection MOS gate electrode 6 by switching the connection of the Z selection MOS gate electrode 6 from the ground voltage to the power source of ⁇ 1V.
- the voltage of the Z selection MOS gate electrode 5 is an intermediate potential. -0,5V. That is, the voltage of the Z selection MOS gate electrode 5 can be controlled to -0.5V without preparing a power supply of -0.5V.
- FIG. 20 is a diagram showing the configuration of the power supply circuit.
- the Dixon type booster circuit has a problem that the voltage value that can be boosted decreases when the threshold voltage of the MOS is high.
- the gate voltage of the transistor of the booster circuit is boosted by the booster circuit SHFT so that the voltage value that can be boosted is not affected by the threshold value of the MOS and can be boosted to a high voltage.
- the memory chain MU is extended in the X direction.
- the Z direction is a direction orthogonal to the silicon substrate, and the X direction and the Y direction are orthogonal to the Z direction and orthogonal to each other. In this way, a plurality of memory cells existing in the Z direction can be collectively formed by a single drilling process, and the manufacturing cost can be reduced.
- the phase change element PCM can be formed not by the CVD method but by the sputter film formation method used for the production of DVD (Digital Versatile Disc). There is no need to newly develop a method for forming the phase change element, and there is an advantage that the development period can be shortened.
- the source voltage Vs as one end voltage is close to the GND potential, and the other end voltage VBL-S is a negative voltage lower than the GND potential. It is the feature that becomes.
- the source voltage of the X selection transistor XTr is lowered to 0 V or less, and the voltage applied to the word lines WL0 to WL7 can be reduced, and the X selection transistor XTr of the non-selected memory chain MU is connected.
- the applied gate-source voltage can be reduced.
- memory chain selection transistors at both ends of the memory chain MU.
- One is SDTr and the other is SSTr.
- a part of the selection operation can be performed by controlling the gate voltages of these transistors using the signal lines SGD and SGS.
- the presence of the memory chain selection transistors at both ends of the memory chain MU causes the inside of the memory chain MU in which the memory chain selection transistor is turned off to be in a floating state and is not easily affected by the disturbance. Can be realized.
- the memory chain selection transistor has a finite resistance, does not completely float the memory chain, and has a parasitic capacitance in the memory chain. Therefore, the memory chain selection transistor is provided at both ends of the memory chain MU. If VBL-S is not a negative voltage lower than the GND potential, the gate-source voltage of the X selection transistor XTr of the unselected memory chain MU is increased, and the reliability of the semiconductor memory device is reduced. It goes without saying that the following problems arise. That is, even in the configuration having the memory chain selection transistors at both ends of the memory chain MU, a highly reliable semiconductor memory device can be realized by using a negative voltage VBL-S lower than the GND potential.
- the reason why the source voltage Vs which is the voltage at one end of the voltages at both ends of the memory chain MU is slightly higher than the GND potential is that there is an electrical resistance between the source wiring and the GND terminal of the semiconductor memory device. Therefore, a slight voltage drop occurs when a current flows between them.
- the circuit shown in FIG. 22 is used as the level shifter circuit.
- this circuit has two levels, a level shifter circuit for high frequency signals and a level shifter circuit for low frequency signals, and the level shifter circuit to be used can be switched using switch 1 and switch 2. is there. This makes it possible to select an optimum level shifter circuit according to the frequency of the signal.
- the wiring for the high frequency signal has a longer wiring interval than the wiring for the low frequency signal. By doing so, it is possible to reduce the parasitic capacitance between the wirings, and to realize a semiconductor memory device that operates at high speed.
- the write time per element is as short as 10 nsec, for example, and the erase time and read time are as long as 300 nsec, for example. For this reason, a level shifter circuit for high frequency signals can be used during writing, and a level shifter circuit for low frequency signals can be used during reading or erasing.
- the signal frequency of the row circuit is a maximum of 100 MHz
- the signal frequency of the row circuit is a maximum of 500 kHz.
- a circuit area can be reduced and a low-cost semiconductor memory device can be realized.
- This circuit first uses a capacitor C and a diode Diode to input a signal on the high voltage side H: 2.3 V and low voltage side L: 0 V, which is an input signal, to the high voltage side: 0 V, and the low voltage side L: -2. .3V signal polarity conversion. Next, by performing amplification using the first stage amplifier circuit and the second stage amplifier circuit, an output signal of high voltage side H: 0V and low voltage side L: -7.5V is generated.
- FIG. 23 shows potentials VZ5 and VZ6 supplied to the Z selection MOS gate electrodes Z5 and Z6 which are part of the memory array 602.
- the power supply voltage -1V is directly supplied to the Z selection MOS gate electrode Z6.
- VZ6 and GND voltage are connected to the Z selection MOS gate electrode Z5 using two resistors, and a voltage generated between them is supplied. It goes without saying that the supply of voltage can be interrupted by providing a switch and supplying a voltage only during a part of the time during writing and turning off the switch during other times.
- 601 Semiconductor memory device, 602 ... Memory array, 603 ... Row system circuit, 604 ... Column system circuit, 605 ... Power supply circuit, 606 ... Command decoder, control circuit, buffer device, 901 ... Z selection transistor gate electrode, 902 ... Interlayer Insulating film, 903... Gate oxide film, 904... Silicon channel, 905... Phase change material, 906... Silicon oxide film, ZTr... Z selection transistor, PCM.
- Potential VBL-S ... selected bit line potential, VBL-US ... unselected bit line potential, VZ ... Z selected line potential, MU, MC ... memory chain, IS ... write current, IUS ... unselected memory chain current, VREF ... Reference voltage, VOUTPUT ... Output voltage, XSEL ... X selection line, XTr ... X selection transistor, S FT ... step-up circuit.
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Abstract
Description
ソース電極の電位VSは、ほぼ0Vである。なお、厳密に述べるとソース電極の電位はソース電極からGND端子に流れる電流による電圧降下により、GND端子の電位である0Vより若干、高くなることは言うまでもない。
V=RI (1)
この電圧降下量Vがライト電圧、例えば7.5Vに対して、無視できない程度に大きいため、メモリ素子における電圧降下を半導体記憶装置601の動作において考慮する必要が生じる。なお、厳密にはZ選択トランジスタにもわずかなオフ電流が流れるため、厳密な電圧降下量は(1)式のものとはわずかに異なる。
既に説明した図1に示された同一の符号を付された構成と、同一の機能を有する部分については、説明を省略する。
Claims (15)
- 直列に接続された複数のメモリセルを含む複数のメモリチェーンを備え、前記メモリセルは、セルトランジスタと電流により書き換えを行う記憶素子であり、前記メモリチェーンは、該記憶素子が並列に接続された構造からなり、電源電圧とグランド電圧が外部から供給されており、前記記憶素子の書き換えに用いる電圧が前記グランド電圧より低いことを特徴とする半導体記憶装置。
- 請求項1において、前記記憶素子が相変化メモリ、ReRAMまたはSTT-MRAMのいずれかであることを特徴とする半導体記憶装置。
- 請求項1において、前記メモリチェーンが少なくとも1個の選択素子を有し、前記選択素子と複数の前記メモリセルが直列接続されていることを特徴とする半導体記憶装置。
- 請求項3において、前記選択素子がMOSFET、またはダイオードであることを特徴とする半導体記憶装置。
- 請求項6において、前記MOSFETがダブルゲート型であることを特徴とする半導体記憶装置。
- 請求項1において、前記メモリチェーンは前記メモリセルを3個以上備え、第1のメモリセルの前記セルトランジスタの第1のゲート電極と、第1のゲート電極と電気容量により電気的に結合された第2のメモリセルの前記セルトランジスタの第2のゲート電極と、第2のゲート電極と電気容量により電気的に結合された第3のメモリセルの前記セルトランジスタの第3のゲート電極を備え、前記第2のゲート電極をフローティング状態にした状態で、前記第1のゲート電極と前記第3のゲート電極に電圧を印加することにより、前記第2のゲート電極の電圧を変化させることを特徴とする半導体記憶装置。
- 請求項1において、メモリチェーンが基板に対して垂直に配置されていることを特徴とする半導体記憶装置。
- 請求項5において、前記選択素子の数が1個であり、メモリチェーンの片端に配置され、もう一方の端がすべてのメモリチェーンに接続されていることを特徴とする半導体記憶装置。
- 請求項1において、前記記憶素子の書き換えにおいて、記憶素子の値を‘0’から‘1’へ書き換えることを消去とし、記憶素子の値を‘1’から‘0’へ書き換えることをライトとするとき、ライトの電圧に用いる電圧が前記グランド電圧より低く、前記消去に用いる電圧が前記グランド電圧より高いことを特徴とする半導体記憶装置。
- 請求項1において、リードに用いる電圧が前記グランド電圧より高く、信号電圧レベル変換回路の数がロウ系回路とカラム系回路の数の合計より多いことを特徴とする半導体記憶装置。
- 請求項1において、Z選択ゲート電圧レベルがライト時より消去時のほうが高く、消去時の電圧水準が5水準以上であることを特徴とする半導体記憶装置。
- 1個の選択トランジスタと直列に接続された複数のメモリセルを含む複数のメモリチェーンを備え、前記選択トランジスタと前記複数のメモリセルは直列に接続され、前記メモリセルはセルトランジスタと電流により書き換えを行う記憶素子が並列に接続された構造からなり、前記メモリチェーンにおいて、前記選択トランジスタを有する側をビット線、有しない側をソース線としたときに、記憶素子をライトするときに前記ソース線に電圧パルスを印加し、前記ビット線の電圧を第1の電圧とし、前記ソース線の前記電圧パルス印加前電圧が前記第1の電圧であり、前記電圧パルス印加中の電圧を第2の電圧とするとき,前記第2の電圧が前記第1の電圧よりも高いことを特徴とする半導体記憶装置。
- 請求項12において,前記記憶素子が相変化メモリであり、前記選択トランジスタがダブルゲート型MOSFETであることを特徴とする半導体記憶装置。
- 1個の選択トランジスタと直列に接続された複数のメモリセルを含む複数のメモリチェーンを備え、前記選択トランジスタと前記複数のメモリセルは直列に接続され、前記メモリセルはセルトランジスタと電流により書き換えを行う記憶素子が並列に接続された構造からなり、前記メモリチェーンにおいて、前記選択トランジスタを有する側をビット線、有しない側をソース線としたときに、記憶素子をライトするときの前記ビット線の電圧を第1の電圧とし、前記ソース線の電圧を第2の電圧としたときに、前記第1の電圧は前記第2の電圧よりも低く、さらに、記憶素子をリードするときの前記ソース線の電圧が前記第2の電圧と等しく、記憶素子をリードするときの前記ビット線の電圧を第3の電圧としたときに、前記第3の電圧が前記第1の電圧よりも高く、
前記ソース線に接続されたメモリチェーンの数が1つの電極に接続された前記セルトランジスタのゲート電極の数以上であることを特徴とする半導体記憶装置。 - 請求項14において,前記記憶素子が相変化メモリであり、前記選択トランジスタがダブルゲート型MOSFETであることを特徴とする半導体記憶装置。
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WO2016143383A1 (ja) * | 2015-03-09 | 2016-09-15 | ソニー株式会社 | メモリセルおよび記憶装置 |
JP2019054197A (ja) | 2017-09-19 | 2019-04-04 | 東芝メモリ株式会社 | 記憶装置 |
KR102575476B1 (ko) | 2018-07-11 | 2023-09-07 | 삼성전자주식회사 | 비휘발성 메모리 장치의 데이터 저장 방법, 데이터 소거 방법 및 이를 수행하는 비휘발성 메모리 장치 |
KR20200056877A (ko) * | 2018-11-15 | 2020-05-25 | 삼성전자주식회사 | 비휘발성 메모리 장치 및 이의 동작 방법 |
EP3718962B1 (en) | 2019-04-01 | 2022-11-09 | IMEC vzw | A method for forming a vertical nanowire or nanosheet field-effect transistor |
KR20200125148A (ko) * | 2019-04-26 | 2020-11-04 | 삼성전자주식회사 | 가변 저항 층을 갖는 반도체 메모리 소자 |
KR20210014497A (ko) | 2019-07-30 | 2021-02-09 | 삼성전자주식회사 | 비휘발성 메모리 장치 및 이의 동작 방법 |
KR20210015102A (ko) | 2019-07-31 | 2021-02-10 | 삼성전자주식회사 | 비휘발성 메모리 장치 및 이의 동작 방법 |
KR20210029870A (ko) | 2019-09-06 | 2021-03-17 | 삼성전자주식회사 | 정보 저장 구조물을 포함하는 반도체 소자 |
US11521663B2 (en) | 2020-07-27 | 2022-12-06 | Taiwan Semiconductor Manufacturing Company, Ltd. | Memory circuit and method of operating same |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2011114016A (ja) * | 2009-11-24 | 2011-06-09 | Toshiba Corp | 半導体記憶装置 |
WO2012032730A1 (ja) * | 2010-09-08 | 2012-03-15 | 株式会社日立製作所 | 半導体記憶装置 |
WO2013183101A1 (ja) * | 2012-06-04 | 2013-12-12 | 株式会社日立製作所 | 半導体記憶装置 |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7961534B2 (en) * | 2007-09-10 | 2011-06-14 | Hynix Semiconductor Inc. | Semiconductor memory device for writing data to multiple cells simultaneously and refresh method thereof |
JP2010283992A (ja) * | 2009-06-04 | 2010-12-16 | Elpida Memory Inc | 電源電圧生成回路、及び半導体装置 |
JP5386528B2 (ja) * | 2011-02-21 | 2014-01-15 | 株式会社日立製作所 | 半導体記憶装置およびその製造方法 |
-
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Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2011114016A (ja) * | 2009-11-24 | 2011-06-09 | Toshiba Corp | 半導体記憶装置 |
WO2012032730A1 (ja) * | 2010-09-08 | 2012-03-15 | 株式会社日立製作所 | 半導体記憶装置 |
WO2013183101A1 (ja) * | 2012-06-04 | 2013-12-12 | 株式会社日立製作所 | 半導体記憶装置 |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109215710A (zh) * | 2017-07-05 | 2019-01-15 | 北京兆易创新科技股份有限公司 | 存储单元及存储器 |
CN109215710B (zh) * | 2017-07-05 | 2024-01-23 | 兆易创新科技集团股份有限公司 | 存储单元及存储器 |
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