JP2007273618A - Resistance-changing memory device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propose a resistance-changing memory device having a low power consumption, having a high cell density, being at a high speed, being non-volatile and resulting in no mistaken reading. <P>SOLUTION: The resistance-changing memory device has a record medium 13 composed of a resistance-changing material changing a resistance value by at lease one of a current and a Joule heat. The resistance-changing memory device further has a layer 17 arranged on the record medium 13 and composed of an anisotropic conductive material having an anisotropy in a high electrical conductivity in the vertical direction to the surface of the record medium 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a resistance change memory device such as a phase-change memory device, and is particularly configured by coupling with a conductive nano-probe array and a scanning probe microscope (SPM). Used for recording / reproducing devices.

  Now that the capacity of magnetic recording devices such as hard disk drives (HDD) is approaching the limit, we will reduce power consumption, reduce cell size, improve cell density, and increase operating speed. Scalable substitutes are being sought that will continue to be possible.

  The alternative is required to have a large capacity of HDD, high speed of DRAM, low cost, and simple mounting on the final product.

  One such alternative is a MEMS (micro electro mechanical systems) memory in which a conductive nanoprobe array is placed on a recording medium (eg, Patent Documents 1 and 2 and Non-Patent Documents). 1-5).

  Some MEMS memories have over 100,000 conductive nanoprobes, or heated conductive AFM probe tips to soften and indent the polymer recording media. ) Is known.

  However, in all designs that use the probe as a read / write device, the sharpness of the probe tip is a limiting factor in order to minimize bit size and thereby maximize recording density.

Therefore, in Non-Patent Document 1, a MEMS probe / cantilever system is adopted, and the recording medium and the probe are set as a system on one chip, that is, SoC (system on chip). In this case, a recording density exceeding 600 gigabits / inch ² is realized with a minimum bit size of 30 nm.

  This is called millipede, and is particularly excellent in reducing power consumption and increasing operating speed.

  In Non-Patent Document 4, a conductive AFM probe array is arranged on a recording medium, similarly to millipedes. The technique disclosed in this document uses a phase change material as a recording medium instead of a polymer recording medium, records data according to a change in the resistance value of the phase change material, and reads out the tip of the conductive AFM probe and the substrate. This is performed by detecting the resistance value by the current flowing between the two.

  In this case, the conductive AFM probe is required to have a function of changing the phase of the phase change material by an electric field or Joule heat.

However, if the phase change of the phase change material is incomplete, a sufficient difference (margin) between the resistance value of “0” data and the resistance value of “1” data cannot be secured, and erroneous data reading is performed. A problem occurs.
JP 2004-326886 A WO-2004-97822 pamphlet “The“ Millipede ”-Nanotechnology Entering Data Storage”, IEEE TRANSACTIONS ON NANOTECHNOLOGY, VOL.1, No.1, MARCH, 2002, pg 39-55, P. Vettiger et al. “Electrical probe storage using Joule heating in phase change media”, Applied Physics Letters, 85, (26), 2004, pg 6392-6394, S. Gidon et al. “Minimal phase-change marks produced in amorphous Ge2Sb2Te5 films”, Japanese Journal of Applied Physics, 43, (6B), 2004, pg L818-L821, T. Gotoh et al. “Nanometer-scale erasable recording using atomic force microscope on phase change media”, Japanese Journal of Applied Physics, 36, 1997, pg 523-525, H. Kado et al. “Understanding the electro-thermal processes involved in probe storage on phase-change media”, Optical Data Storage, 2003, M. Armand et al. “Growth process of vertically aligned single-walled carbon nanotubes”, Shigeo Maruyama *, Erik Einarsson, Yoichi Murakami, Tadao Edamura, Chemical Physics Letters 403, 320 (2005). “Creation of Highly Oriented Freestanding Carbon Nanotube Film by Subliminating Decomposition of Silicon Carbide Film”, T. Shimizu, Y. Ishikawa, M. Kusunoki, T. Nagano, and N. Shibata, Japanese Journal of Applied Physics 39, L1057 (2000) .

  The example of the present invention proposes a resistance change memory device with low power consumption, high cell density, high speed and non-volatility and without erroneous reading.

  A resistance change memory device according to an example of the present invention includes a recording medium composed of a resistance change material whose resistance value is changed by at least one of current and Joule heat, and a recording medium disposed on the recording medium, with respect to the surface of the recording medium. And a layer made of an anisotropic conductive material having anisotropy that the electric conductivity in the vertical direction is higher than the electric conductivity in directions other than the vertical direction.

  A conductive probe device according to an example of the present invention includes a resistance change memory device and a conductive probe arranged to face the resistance change memory device. The resistance change memory device includes a recording medium composed of a resistance change material whose resistance value is changed by at least one of current and Joule heat, and an electric conduction in a direction perpendicular to the surface of the recording medium. And a layer made of an anisotropic conductive material having anisotropy having a degree higher than the electric conductivity in a direction other than the vertical direction. Then, using a conductive probe, at least one of current and Joule heat is applied to the recording medium through a layer made of an anisotropic conductive material.

  A resistance change memory device according to an example of the present invention includes first and second conductive lines intersecting each other and a memory cell connected between the first and second conductive lines. The memory cell has a recording layer made of a resistance change material whose resistance value changes according to at least one of current and Joule heat, and anisotropy that electric conductivity is high in a direction perpendicular to the surface of the recording layer. It has a stack structure with a layer composed of an anisotropic conductive material.

  According to the example of the present invention, a resistance change memory device with low power consumption, high cell density, high speed and non-volatility and no erroneous reading can be realized.

  The best mode for carrying out an example of the present invention will be described below in detail with reference to the drawings.

1. Overview
An example of the present invention relates to a resistance change memory device using a resistance change material whose resistance value is changed by at least one of current (electric field) and Joule heat as a recording medium, on the recording medium in a direction perpendicular to the surface thereof. It is characterized in that a layer (conductive layer) made of an anisotropic conductive material having anisotropy that the electric conductivity is higher than the electric conductivity in a direction other than the vertical direction is disposed.

The resistance change material is, for example, a phase change material, and the anisotropic conductive material is, for example, SWNT (single walled carbon nanotube) and MWNT (multi walled carbon nanotube) having an axial direction oriented perpendicular to the substrate surface, It is composed of one of K _0.3 MoO ₃ and K _0.3 RuO ₃ . The thickness of the anisotropic conductive material is set to a value in the range of 5 nm to 15 nm.

  When a conductive nanoprobe is arranged on the resistance change memory device and the conductive probe device is configured, at least one of current (electric field) and Joule heat is anisotropically conducted using the conductive nanoprobe. Setting (writing) / resetting operation can be performed by applying to a recording medium made of a resistance change material through a layer made of the material.

  Moreover, if the position of the resistance change memory device is controlled by an X / Y scanner, the position of the conductive nanoprobe is controlled by a driver, and the conductive nanoprobe is connected to a measuring device such as a scanning probe microscope (SPM). A recording / reproducing apparatus can be realized.

  SPM is a general term for scanning probe microscopes such as STM (scanning tunneling microscope) and AFM (atomic force microscope).

2. Reference example
First, a reference example as a premise of the present invention will be described.

The reference example relates to a phase change memory device and a recording / reproducing device using the same.
FIG. 1 shows an outline of a recording / reproducing apparatus according to a reference example.

The main components of the phase change memory device 11 are a lower electrode 12, a recording medium 13 made of a phase change material on the lower electrode 12, and a conductive layer 14 on the recording medium 13. The lower electrode 12 is made of, for example, metal, the recording medium 13 is made of, for example, GST (Ge ₂ Sb ₂ Te ₅ ), and the conductive layer 14 is made of, for example, a thin insulator.

  A conductive probe 16 is connected to the conductive AFM (conductive AFM) 15, and the conductive probe 16 can perform two-dimensional or three-dimensional operation.

  Here, in the initial state, as shown in FIG. 2, it is assumed that the recording medium 13 is amorphous and has a high resistance value (high ρ).

  In the setting (writing) process, first, the conductive probe 16 is driven by an access operation, and the tip thereof is brought into contact with the conductive layer 14 above the selected address of the recording medium 13.

Thereafter, the first current pulse is supplied to the selected address of the recording medium using the conductive AFM 15. Then, as shown in FIG. 3, for example, the electron e ⁻ moves to the selected address of the recording medium via the tip of the conductive probe 16 and the conductive layer, and raises the temperature of the address. When the temperature exceeds the glass transition temperature, as shown in FIG. 4, the address changes to crystalline and becomes a low resistance value (low ρ).

  In the reset process, first, the conductive probe 16 is driven by an access operation, and its tip is brought into contact with the conductive layer 14 above the selected address of the recording medium 13.

Thereafter, a second current pulse larger than the first current pulse is supplied to the selected address of the recording medium using the conductive AFM 15. Then, as shown in FIG. 5, for example, the electron e ⁻ moves to the selected address of the recording medium via the tip of the conductive probe 16 and the conductive layer, and raises the temperature of the address. When the temperature exceeds the melting point of the recording medium, as shown in FIG. 6, the address changes to amorphous and becomes a high resistance value (high ρ).

  However, in the reset process, all the selected addresses of the recording medium 13 are not made amorphous. This is considered to be caused by a temperature gradient in which the portion near the tip of the conductive probe 16 is hotter than the other portions, but it is difficult to eliminate this.

  Therefore, as shown in FIG. 7, when viewed from the top of the recording medium 13, there is a crystal portion of a low resistance value (low ρ) in the shape of a circular light (halo) around the address that has been made amorphous by the reset process. Will remain.

In this case, when a read current is made to flow through the address at the time of reading, electrons e ⁻ emitted from the tip of the conductive probe 16 preferentially flow through the low-resistance crystal part as shown in FIG. The correct resistance value at that address cannot be read out, and erroneous reading occurs.

Further, even if an attempt is made to crystallize the address again from this state by the set process, as shown in FIG. 8, the electron e ⁻ emitted from the tip of the conductive probe 16 has a low resistance. Therefore, there is a problem that writing cannot be performed repeatedly.

3. Embodiment
Next, some preferred embodiments will be described.
In the following embodiments, a phase change memory device that is a typical example of a resistance change memory device and a recording / reproducing apparatus using the phase change memory device will be described.

(1) First embodiment
A. Structure
FIG. 9 shows an outline of the recording / reproducing apparatus according to the first embodiment.

The main components of the phase change memory device 11 are a lower electrode 12, a recording medium 13 made of a phase change material on the lower electrode 12, and a conductive layer 14 on the recording medium 13. The lower electrode 12 is made of, for example, a metal, the recording medium 13 is made of, for example, GST (Ge ₂ Sb ₂ Te ₅ ), and the conductive layer 14 is made of an anisotropic conductive material.

  A conductive probe 16 is connected to the conductive AFM 15, and the conductive probe 16 can perform a two-dimensional or three-dimensional operation.

  Here, the anisotropic conductive material is a flexible material that has low contact resistance of the conductive probe 16 and less wear due to contact of the conductive probe 16. The anisotropic conductive material has an anisotropy that the electric conductivity in the direction perpendicular to the surface of the recording medium 13 is higher than the electric conductivity in a direction other than the perpendicular direction.

For example, SWNT, K _0.3 MoO ₃ , K _0.3 RuO _{3, and the} like are promising candidates for anisotropic conductive materials having such characteristics.

  For example, in the case of SWNT, a large number of aligned cylindrical molecules are oriented in a direction perpendicular to the surface of the recording medium 13, so that the electrical conductivity of the conductive layer 14 in the perpendicular direction is determined by the surface of the recording medium 13. In contrast, the electric conductivity of the conductive layer 14 in the horizontal direction is sufficiently larger. In this case, electrons emitted from the conductive probe 16 flow along the trajectory of the cylindrical molecule, so that no leakage current flows outside the selected address of the recording medium 13.

  Therefore, even when a crystal part having a low resistance value (low ρ) in the form of a circular light (halo) is formed around the selected address of the recording medium 13 when changing from the set state to the reset state, Alternatively, at the time of writing again, electrons do not leak into the circular crystal portion, and prevention of erroneous reading and repetition of writing can be realized.

  The thickness of the anisotropic conductive material is determined in consideration of the following points.

  A sufficient thickness that does not damage the recording medium 13 due to fraying caused by contact with the conductive probe 16.

  The thickness is sufficient to prevent the recording medium 13 from being oxidized or evaporated.

  The anisotropic conductive material is sufficiently thin so that the anisotropy of the anisotropic conductive material is thin and no current path is generated at an address adjacent to the selected address of the recording medium 13.

  The distance between the recording medium 13 and the conductive probe 16 is not too far away and is thin enough to realize low power consumption.

  Considering the above points, the thickness of the anisotropic conductive material is preferably set to a value within the range of 5 nm to 15 nm.

B. Operation
Next, the operation of the recording / reproducing apparatus in FIG. 9 will be described.

  In the initial state, as shown in FIG. 10, it is assumed that the recording medium 13 is amorphous and has a high resistance value (high ρ).

  In the set (write) process, first, the conductive probe 16 is driven by an access operation, and the tip thereof is brought into contact with the conductive layer 14 above the selected address of the recording medium 13.

Thereafter, the first current pulse is supplied to the selected address of the recording medium using the conductive AFM. Then, as shown in FIG. 11, for example, the electron e ⁻ moves to the selected address of the recording medium via the tip of the conductive probe 16 and the conductive layer, and raises the temperature of the address. When the temperature exceeds the glass transition temperature, as shown in FIG. 12, the address changes to crystalline and becomes a low resistance value (low ρ).

  In the reset process, first, the conductive probe 16 is driven by an access operation, and the tip thereof is brought into contact with the conductive layer 14 above the selected address of the recording medium 13.

Thereafter, a second current pulse larger than the first current pulse is supplied to the selected address of the recording medium using the conductive AFM. Then, as shown in FIG. 13, for example, the electron e ⁻ moves to the selected address of the recording medium via the tip of the conductive probe 16 and the conductive layer, and raises the temperature of the address. When the temperature exceeds the melting point of the recording medium, as shown in FIG. 14, the address changes to amorphous and becomes a high resistance value (high ρ).

  Here, as described in the reference example, in the reset process, all the selected addresses of the recording medium 13 are not made amorphous. Therefore, as shown in FIG. 15, when viewed from the top of the recording medium 13, a crystal having a low resistance value (low ρ) in the form of a circular light (halo) is formed around the address that has been made amorphous by the reset process. Department remains.

  However, in the first embodiment, the problem that erroneous reading and writing cannot be performed repeatedly as shown in the reference example does not occur.

This is because, when a read current is passed through the address during reading, electrons e ⁻ emitted from the tip of the conductive probe 16 pass through the anisotropic conductive material constituting the conductive layer 14 as shown in FIG. This is because it flows concentrated in the high-resistance amorphous part of the address.

  Therefore, an accurate resistance value at the address can be read out.

In addition, when the address is to be crystallized again from the state shown in FIG. 15 by the set process, the electrons emitted from the tip of the conductive probe 16 are also shown in FIG. Since e ⁻ flows through the anisotropic conductive material constituting the conductive layer 14 in a concentrated manner at the high-resistance amorphous part at the address, writing can be repeated.

C. Summary
As described above, according to the first embodiment, the layer that covers the recording medium is made of an anisotropic conductive material, so that the read margin can be increased with low power consumption, high cell density, high speed, and non-volatility. A change memory device can be realized.

(2) Second embodiment
FIG. 17 shows an outline of a recording / reproducing apparatus according to the second embodiment.

  The phase change memory device 11 according to the example of the present invention is formed on the semiconductor chip 20 </ b> A and disposed on the X / Y scanner 18. The X / Y scanner 18 controls the position of the phase change memory device 11 in two dimensions.

  A semiconductor chip 20B having a cantilever array 19 as a conductive probe array is disposed on the phase change memory device 11 so as to face the memory cell. The recording medium in the phase change memory device 11 is divided into a plurality of areas corresponding to the cantilever array 19. The plurality of cantilevers 19 are driven by multiplex drivers 21 and 22.

  The read / write (set) operation and the reset operation can be performed simultaneously on a plurality of cantilevers 19 or can be performed for each cantilever 19. The cantilever array 19 can be formed by, for example, MEMS technology.

  This recording / reproducing apparatus approximates millipedes, but has the following advantages over millipedes.

  In changing the phase of the selected address of the recording medium, not only the heat can be conducted from the cantilever 19 to the address, but also heating is performed while a current is passed through the address, so that the set / reset operation can be performed at high speed. it can.

  Further, the cantilever 19 does not need to be operated in three dimensions due to the flexibility of the layer made of an anisotropic conductive material. That is, the cantilever 19 is always kept in contact with a layer made of an anisotropic conductive material, and the access operation may be performed by driving the cantilever 19 two-dimensionally by the multiplex drivers 21 and 22.

  Therefore, the drive mechanism of the cantilever 19 is simplified, and it can contribute to the miniaturization of the system as the manufacturing cost decreases.

(3) Third embodiment
The third embodiment relates to a case where the phase change memory device is applied to a PRAM (phase-change random access memory) as a nonvolatile semiconductor memory.

A. Structure
FIG. 18 shows a cross-point type PRAM.

  Word lines WLi−1, WLi, and WLi + 1 extend in the X direction, and bit lines BLj−1, BLj, and BLj + 1 extend in the Y direction.

  One end of the word lines WLi-1, WLi, WLi + 1 is connected to the word line driver & decoder 31 via a MOS transistor RSW as a selection switch, and one end of the bit lines BLj-1, BLj, BLj + 1 is used as a selection switch. The bit line driver & decoder & read circuit 32 is connected via the MOS transistor CSW.

  Selection signals Ri-1, Ri, Ri + 1 for selecting one word line (row) are inputted to the gate of the MOS transistor RSW, and one bit line (column) is inputted to the gate of the MOS transistor CSW. Selection signals Ci-1, Ci, Ci + 1 are input to select.

  Memory cell 33 is arranged at the intersection of word lines WLi-1, WLi, WLi + 1 and bit lines BLj-1, BLj, BLj + 1. This is a so-called cross-point cell array structure.

  The memory cell 33 is provided with a diode 34 for preventing a sneak current during recording / reproduction.

FIG. 19 shows the structure of the memory cell array.
On the semiconductor chip 30, word lines WLi-1, WLi, WLi + 1 and bit lines BLj-1, BLj, BLj + 1 are arranged, and memory cells 33 and diodes 34 are arranged at intersections of these wirings.

  Such a cross-point cell array structure is advantageous in high integration because it is not necessary to connect a MOS transistor to each memory cell 33 individually. For example, as shown in FIGS. 20 and 21, it is possible to stack the memory cells 33 to make the memory cell array have a three-dimensional structure.

  For example, as shown in FIG. 22, the memory cell 33 includes a stack structure of a recording layer (recording medium) 13 made of a phase change material, a conductive layer 17 made of an anisotropic conductive material, and a heater layer 35. Is done.

Anisotropic conductive material, SWNT having anisotropy of higher electrical conductivity in a direction other than the vertical electrical conductivity in the direction perpendicular to the surface of the recording layer 13, and K _0.3 MoO _3, K _0.3 Consists of RuO _{3 and} others.

  The heater layer 35 is made of a material having a property of generating Joule heat when a current flows.

  One bit data is stored in one memory cell 33. The diode 34 is disposed between the word line WLi and the memory cell 33.

  The positional relationship among the recording layer 13, the conductive layer 17, and the heater layer 35 is not limited to the case shown in FIG.

B. Operation
The recording / reproducing operation will be described with reference to FIGS.
Here, it is assumed that the memory cell 33 surrounded by the dotted line A is selected, and the recording / reproducing operation is executed for this.

  In the set (write) operation, it is only necessary to apply a voltage to the selected memory cell 33, generate a potential gradient in the memory cell 33, and flow the first current pulse. For example, the potential of the word line WLi is a bit. A state that is relatively lower than the potential of the line BLj is created. If the bit line BLj is set to a fixed potential (for example, a ground potential), a negative potential may be applied to the word line WLi.

At this time, in the selected memory cell 33 surrounded by the dotted line A, the electrons e ⁻ move from the word line WLi to the bit line BLj through the memory cell 33 surrounded by the dotted line A. The temperature rises. When the temperature exceeds the glass transition temperature for a certain time (typically about 100 ns to 1 μs) or longer, the recording medium changes to a crystal and has a low resistance value.

  In the reset operation, a voltage is applied to the selected memory cell 33, a potential gradient is generated in the memory cell 33, and a second current pulse larger than the first current pulse is allowed to flow. For example, a state is created in which the potential of the word line WLi is relatively lower than the potential of the bit line BLj.

At this time, in the selected memory cell 33 surrounded by the dotted line A, the electrons e ⁻ move from the word line WLi to the bit line BLj via the memory cell 33 surrounded by the dotted line A. The temperature rises. Then, after the temperature exceeds the melting point of the recording medium, the current is interrupted, and further, when the heat is rapidly cooled by escaping to the surroundings, the recording medium changes to amorphous and has a high resistance value.

  In the read operation, a read current may be supplied to the selected memory cell 33 from the read circuit. At this time, since the read current flows through the conductive layer that is an anisotropic conductive material, for example, even if the recording medium has a halo-shaped crystal part in the reset state, Since read current does not flow in a concentrated manner, erroneous reading can be prevented.

  During the set / reset operation, it is preferable that the unselected word lines WLi−1 and WLi + 1 and the unselected bit lines BLj−1 and BLj + 1 are all biased to the same potential.

  In standby before the set / reset operation, it is preferable to precharge all the word lines WLi−1, WLi, and WLi + 1 and all the bit lines BLj−1, BLj, and BLj + 1.

  The first and second current pulses may be generated by creating a state in which the potential of the word line WLi is relatively higher than the potential of the bit line BLj.

With respect to the read operation, it is necessary to make the value small enough that the phase change material as a recording medium does not cause a phase change by the read current. The difference between the resistance values in the set / reset state can be 10 ³ Ω or more.

C. Summary
Thus, the phase change memory device according to the example of the present invention can be applied to a nonvolatile semiconductor memory, and even in such a case, effects such as prevention of erroneous reading and repetition of writing can be obtained. be able to.

4). Conclusion
According to the example of the present invention, it is possible to realize a resistance change memory device that has low power consumption, high cell density, high speed, and non-volatility and can have a large read margin.

  The example of the present invention is not limited to the above-described embodiment, and can be embodied by modifying each component without departing from the scope of the invention. Various inventions can be configured by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, some constituent elements may be deleted from all the constituent elements disclosed in the above-described embodiments, or constituent elements of different embodiments may be appropriately combined.

The figure which shows the recording / reproducing apparatus in connection with a reference example. The figure which shows the initial state of a phase change memory device. The figure which shows the state in the set process of a phase change memory device. The figure which shows the set state of a phase change memory device. The figure which shows the state in the reset process of a phase change memory device. The figure which shows the reset state of a phase change memory device. The figure which shows the circular crystal part in a reset state. The figure which shows the state in the read / set process of a phase change memory device. The figure which shows the recording / reproducing apparatus in connection with 1st Embodiment. The figure which shows the initial state of a phase change memory device. The figure which shows the state in the set process of a phase change memory device. The figure which shows the set state of a phase change memory device. The figure which shows the state in the reset process of a phase change memory device. The figure which shows the reset state of a phase change memory device. The figure which shows the circular crystal part in a reset state. The figure which shows the state in the read / set process of a phase change memory device. The figure which shows the recording / reproducing apparatus in connection with 2nd Embodiment. The circuit diagram which shows PRAM in connection with 3rd Embodiment. The figure which shows the example of the device structure of PRAM. The figure which shows the example of the device structure of PRAM. The figure which shows the example of the device structure of PRAM. The figure which shows the example of a memory cell structure.

Explanation of symbols

  11: Phase change memory device, 12: Lower electrode, 13: Recording medium (phase change material), 14: Conductive layer, 15: Conductive AFM, 16: Conductive probe, 17: Conductive layer (anisotropic conductive material) 18: X / Y scanner, 19: Cantilever array, 20, 30: Semiconductor chip, 21, 22: Multiplex driver, 31: Word line driver & decoder, 32: Bit line driver & decoder & read circuit, 33: Memory Cell, 34: diode, 35: heater layer.

Claims (7)

  A recording medium composed of a variable resistance material whose resistance value changes according to at least one of current and Joule heat, and an electrical conductivity in a direction perpendicular to the surface of the recording medium disposed on the recording medium; And a layer formed of an anisotropic conductive material having anisotropy higher than the electric conductivity in a direction other than the direction. The anisotropic conductive material is one selected from the group consisting of SWNT (single walled carbon nanotube), MWNT (multi walled carbon nanotube), K _0.3 MoO ₃ and K _0.3 RuO _3. 2. The resistance change memory device according to 1.   3. The resistance change memory device according to claim 1, wherein the thickness of the anisotropic conductive material is set to a value within a range of 5 nm to 15 nm. Comprising a resistance change memory device and a conductive probe disposed opposite to the resistance change memory device;
The resistance change memory device includes a recording medium made of a resistance change material whose resistance value is changed by at least one of current and Joule heat, and a recording medium disposed on the recording medium and perpendicular to the surface of the recording medium A layer composed of an anisotropic conductive material having anisotropy that the electrical conductivity of is higher than the electrical conductivity in a direction other than the vertical direction,
A conductive probe device that applies at least one of the current and Joule heat to the recording medium through the layer made of the anisotropic conductive material using the conductive probe.   The resistance change memory device is formed on a first semiconductor chip, and the conductive probe is a cantilever formed on a second semiconductor chip disposed to face the first semiconductor chip. The conductive probe device according to claim 4. First and second conductive lines intersecting each other, and a memory cell connected between the first and second conductive lines,
The memory cell includes a recording layer made of a resistance change material whose resistance value changes according to at least one of current and Joule heat, and an electrical conductivity in a direction perpendicular to the surface of the recording layer other than the perpendicular direction. A resistance change memory device having a stack structure with a layer made of an anisotropic conductive material having anisotropy higher than an electric conductivity in a direction.   The resistance change memory device according to claim 6, wherein the memory cell further includes a heater layer that generates Joule heat by the current.

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