JP5672143B2 - Control method of resistance change element and semiconductor device - Google Patents

Description

  The present invention relates to a resistance change element control method and a semiconductor device, and more particularly, to a resistance change element writing and erasing programming method and a semiconductor device such as a memory and an FPGA having a resistance change element.

  Semiconductor devices, particularly silicon devices, have been advanced at higher pace and lower power by miniaturization, and have been developed at a pace (Moore's scaling rule) where the integration density is quadrupled in 3 years. However, in recent years, the gate length of MOSFET (Metal Oxide Semiconductor Field Effect Transistor) has become 20 nm or less, and due to soaring lithography process (apparatus price, mask set price) and physical limitations (operation limits, dispersion limits) of device dimensions. There is a need to improve device performance through an approach different from previous scaling laws.

  As one of such approaches, a field programmable gate array (FPGA), which is positioned between a gate array and a standard cell, has recently been developed. The FPGA is a rewritable programmable logic device and has a variable resistance nonvolatile element (hereinafter referred to as “resistance variable element”) inside a multilayer wiring layer. According to the FPGA, after the chip is manufactured, the customer can arbitrarily connect the wirings to form a circuit. By using a semiconductor device mounted with an FPGA, the degree of freedom of the circuit can be improved.

  As a resistance change element, ReRAM (Resistance Random Access Memory) using a transition metal oxide, NanoBridge (registered trademark) using an ionic conductor, and the like are known. Non-Patent Documents 1 and 2 describe resistance change elements that utilize the movement of metal ions in a solid (that is, an ion conductor) in which ions can freely move by application of an electric field or the like, and an electrochemical reaction. Has been. The resistance change element described in Non-Patent Documents 1 and 2 includes an ion conductive layer, and a first electrode and a second electrode provided on the opposite surface of the ion conductive layer in contact with the ion conductive layer. Metal ions are supplied from the first electrode to the ion conductive layer. On the other hand, metal ions are not supplied from the second electrode to the ion conductive layer. In the resistance change elements described in Non-Patent Documents 1 and 2, the resistance value of the ion conductor is changed by changing the polarity of the applied voltage to control the conduction state between the two electrodes.

  Technologies related to the resistance change element are described in, for example, Patent Documents 1 to 4. Patent Document 3 describes a control method in which positive and negative voltages are alternately applied to cause a resistance change element to alternate between a high resistance state and a low resistance state.

JP 2010-103555 A JP 2010-225221 A Japanese Patent No. 4607252 Japanese Patent No. 4643767

M.M. Tada, T .; Sakamoto, N .; Banno, M .; Aono, H .; Hada and N.M. Kasai, “Nonvolatile Crossbar Switching TiOx / TaSiOy Solid-electrolyte,” IEEE Transactions on Electron Devices, vol. 57, no. 8, pp. 1987-1995 (2010). M.M. Tada, T .; Sakamoto, K .; Okamoto, M .; Miyamura, N .; Banno, Y. et al. Katoh, S .; Ishida, N .; Iguchi, N .; Sakimura, H .; Hada, "Polymer Solid-Electrolyte (PSE) Switch Embedded in 90nm CMOS with Forming-free and 10nsec Programming for Low Power, Nonvolatile Programmable Logic (NPL)," IEEE International Electron Devices Meeting, (2010, San Francisco, USA), pp . 403-406 (2010).

  The following analysis was made by the present inventors.

  For example, when the two-terminal variable resistance element described in Non-Patent Documents 1 and 2 is used for a ULSI signal line, the resistance value is changed by applying a voltage exceeding the threshold voltage between the electrodes. Can do. The threshold voltage at this time is about 2 to 4 V, but the threshold voltage is preferably about 1 V, which is the operating voltage of the CMOS transistor.

  Since the threshold voltage depends on the electric field strength between metal-insulator-metal (MIM: Metal-Insulator-Metal), it is conceivable to reduce the threshold voltage by reducing the film thickness between the electrodes. . However, as the threshold voltage is lowered, there is a problem that the threshold voltage varies and the programming operation becomes unstable.

  Furthermore, a constant current value is required to make a transition (hereinafter referred to as “erase”) from the low resistance state (ON state) to the high resistance state (OFF state). A large erasing current is required as the resistance becomes low, and a programming transistor having a large driving force needs to be adopted to flow a large current, which causes a problem of increasing the chip area.

  Therefore, it is a problem to reduce the threshold voltage without causing variations in the threshold voltage of the resistance change element. An object of the present invention is to provide a semiconductor device and a resistance change element control method for solving such problems.

The control method of the resistance change element according to the first aspect of the present invention is as follows.
A resistance change layer that transitions between a first state and a second state having different resistance values according to the polarity of the applied pulse voltage; a first electrode connected to one end of the resistance change layer; A control method of a resistance change element including a second electrode connected to the other end,
A first pulse voltage having a second polarity opposite to a first polarity for causing the resistance change layer to transition from the first state to the second state is applied to the resistance change layer in the first state. Maintaining between the first electrode and the second electrode,
After applying the first pulse voltage, a second pulse voltage having the first polarity is applied between the first electrode and the second electrode, and the resistance change layer is moved to the first electrode. Transitioning from one state to the second state.
Here, the variable resistance layer is an ion conductive layer containing at least silicon (Si), oxygen (O), and carbon (C), the first electrode contains copper (Cu), and the second electrode Includes ruthenium (Ru).

A semiconductor device according to a second aspect of the present invention is:
A resistance change layer that transitions between a first state and a second state having different resistance values according to the polarity of the applied pulse voltage;
A first electrode connected to one end of the variable resistance layer;
A second electrode connected to the other end of the variable resistance layer;
A first pulse voltage having a second polarity opposite to a first polarity for causing the resistance change layer to transition from the first state to the second state is applied to the resistance change layer in the first state. The second pulse voltage having the first polarity is applied between the first electrode and the second electrode after being applied between the first electrode and the second electrode. And a programming circuit that causes the resistance change layer to transition from the first state to the second state.
Here, the variable resistance layer is an ion conductive layer containing at least silicon (Si), oxygen (O), and carbon (C), the first electrode contains copper (Cu), and the second electrode Includes ruthenium (Ru).

  According to the variable resistance element control method and the semiconductor device according to the present invention, the threshold voltage can be lowered without causing variations in the threshold voltage of the variable resistance element.

It is a figure which shows an example of the operation characteristic of a unipolar type | mold switch element. It is a figure which shows an example of the operating characteristic of a bipolar type switch element. It is a figure for demonstrating an example of the control method of the variable resistance element which concerns on embodiment. It is a figure which shows the structure of a resistance change element as an example. It is a figure which shows the structure of the semiconductor device for implement | achieving the control method of the resistance change element which concerns on embodiment as an example. It is a figure for demonstrating an example (the writing method, the transition from an OFF state to an ON state) of the control method of the resistance change element which concerns on embodiment. It is a figure for demonstrating an example (the erasing method, the transition from an ON state to an OFF state) of the control method of the resistance change element which concerns on embodiment.

  First, the outline of the present invention will be described. Note that the reference numerals of the drawings attached to this summary are merely examples for facilitating understanding, and are not intended to limit the present invention to the illustrated embodiment.

  Referring to FIGS. 3 and 4, the resistance change element control method according to the present invention includes a first state (OFF state / ON state) and a second state having different resistance values according to the polarity of the applied pulse voltage. A resistance change layer (for example, ion conductive layer 113) that transitions between (ON state / OFF state), a first electrode (110) connected to one end of the resistance change layer (113), and a connection to the other end The resistance change element is provided with the second electrode (114), and the resistance change layer (113) is changed from the first state (OFF state / ON state) to the second state (ON state / The first pulse voltage having the second polarity opposite to the first polarity to be shifted to the OFF state) (the pulse voltage in the reverse direction in FIG. 3) is applied to the variable resistance layer 113 in the first state (OFF State / ON state) while maintaining the first electrode (110) and the second electrode (114) and after applying the first pulse voltage, the second pulse voltage having the first polarity (programming pulse voltage in FIG. 3) is connected to the first electrode (110). Applying between the second electrode (114) and transitioning the variable resistance layer (113) from the first state (OFF state / ON state) to the second state (ON state / OFF state); ,including.

  Referring to FIG. 5, the semiconductor device of the present invention has a resistance change layer (for example, an ion conduction layer) that transitions between a first state and a second state having different resistance values according to the polarity of an applied pulse voltage. 113), a first electrode (110) connected to one end of the resistance change layer (113), a second electrode (114) connected to the other end of the resistance change layer (113), and the resistance change layer A first pulse voltage having a second polarity opposite to the first polarity that causes (113) to transition from the first state to the second state is maintained in the resistance change layer (113) in the first state. However, after being applied between the first electrode (110) and the second electrode (114), a second pulse voltage having the first polarity is applied to the first electrode (110) and the second electrode ( 114) to change the resistance change layer (113) from the first state to the second state. It includes a programming circuit.

  According to the variable resistance element control method and the semiconductor device according to the present invention, the threshold voltage can be lowered without causing variations in the threshold voltage of the variable resistance element.

In the present invention, the following modes are possible.
[Form 1]
It is as the control method of the resistance change element concerning the said 1st viewpoint.
[Form 2]
In the control method of the resistance change element, the first pulse voltage is applied twice or more between the first electrode and the second electrode, and then the second pulse voltage is applied to the first electrode and the second electrode. You may make it apply between.
[Form 3]
In the variable resistance element control method, the pulse width of the second pulse voltage may be wider than the pulse width of the first pulse voltage.
[Form 4]
In the variable resistance element control method, the interval between the first pulse voltage and the second pulse voltage may be 10 nsec (nanoseconds) or less.
[Form 5]
In the variable resistance element control method, the first state may be an off state (high resistance state), and the second state may be an on state (low resistance state).
[Form 6]
In the variable resistance element control method, the first pulse voltage may be 3 V or less and 10 μsec (microseconds) or less.
[Form 7]
In the variable resistance element control method, the first state may be an on state and the second state may be an off state.
[Form 8]
In the variable resistance element control method, the first pulse voltage may be 0.2 V or less and 1 μsec or less.
[Form 9]
In the resistance change element control method, the current value flowing through the resistance change element when the first pulse voltage is applied may be equal to or less than the current value flowing through the resistance change element when the second pulse is applied. .
[Mode 10]
In the resistance change element control method, the current value flowing through the resistance change element when the first pulse voltage is applied may be equal to the current value flowing through the resistance change element when the second pulse is applied.
[Form 11]
This is as the semiconductor device according to the second aspect.
[Form 12]
In the semiconductor device, the variable resistance layer may be an ion conductive layer containing at least silicon (Si), oxygen (O), and carbon (C).
[Form 13]
In the semiconductor device, the first electrode may contain copper (Cu).
[Form 14]
In the above semiconductor device, the second electrode may contain ruthenium (Ru).

(Embodiment)
A method for controlling a switch element according to an embodiment will be described with reference to the drawings. Before describing the embodiment in detail, the meaning of terms in the present embodiment will be described. First, the “unipolar switch element” and the “bipolar switch element” will be described.

  The “unipolar switch element” refers to a switch element that switches between an OFF state (high resistance state) and an ON state (low resistance state) according to the level of applied voltage. FIG. 1 is a diagram schematically showing operating characteristics of a unipolar switch element. With reference to FIG. 1, the operation characteristics of the unipolar switch element will be described.

  Referring to FIG. 1A, for example, in the case of a unipolar variable resistance element including a first electrode, a switch element, and a second electrode, when a positive voltage is applied to the first electrode, a predetermined set voltage is set to a threshold voltage. As described above, the switch element transitions from the OFF state (high resistance state) to the ON state (low resistance state). Here, the threshold voltage depends on the film thickness, composition, density, and the like of the resistance change layer.

  Referring to FIG. 1B, when a positive voltage is applied again to the first electrode in the switch element in the ON state, the switch element transitions from the ON state to the OFF state using a predetermined reset voltage as a threshold voltage. Further, when the positive voltage is continuously applied and the voltage value reaches the set voltage, the switch element again transitions from the OFF state to the ON state.

  Referring to FIG. 1C, when a negative voltage is applied to the first electrode and the absolute value of the voltage is increased, a predetermined set voltage is set as a threshold voltage, and the switch element is in an OFF state (high resistance State) to ON state (low resistance state).

  Referring to FIG. 1D, in the switch element in the ON state, when a negative voltage is again applied to the first electrode and the absolute value of the voltage is increased, the switch element is changed from the ON state to a predetermined reset voltage as a threshold voltage. Transition to OFF state.

  Referring to FIGS. 1A to 1D, the operation when a positive voltage is applied to the first electrode (FIGS. 1A and 1B) and the operation when a negative voltage is applied (FIG. 1 ( c) and (d)) are symmetrical. That is, the characteristic (resistance value) of the variable resistance element does not depend on the voltage application direction (polarity), but only on the magnitude (level) of the voltage. A switch element exhibiting such resistance change characteristics is referred to as a “unipolar switch element”.

  On the other hand, the “bipolar switch element” refers to a switch element that switches between an OFF state (high resistance state) and an ON state (low resistance state) according to the polarity of an applied voltage. FIG. 2 is a diagram schematically showing the operating characteristics of the bipolar switch element. With reference to FIG. 2, the operating characteristics of the bipolar switch element will be described.

  Referring to FIG. 2 (a), for example, in the case of a bipolar switch element including a first electrode, an ionic conductor and a second electrode, when a positive voltage is applied to the first electrode, a predetermined set voltage is set to a threshold voltage. As a result, the switch element transitions from the OFF state to the ON state.

  Referring to FIG. 2B, in the variable resistance element in the ON state, when a positive voltage is applied again to the first electrode, the switch element exhibits ohmic current-voltage characteristics.

  Referring to FIG. 2C, in the variable resistance element in the ON state, when a negative voltage is applied to the first electrode and the absolute value of the voltage is increased, the switch element is in the ON state (with a predetermined reset voltage as a threshold voltage). Transition from the low resistance state to the OFF state (high resistance state).

  Referring to FIG. 2D, when a positive voltage is applied again to the first electrode in the variable resistance element in the OFF state, the switch element transitions from the OFF state to the ON state using a predetermined threshold voltage as a set voltage.

  A switch element that switches between the OFF state (high resistance state) and the ON state (low resistance state) according to the polarity of the applied voltage is referred to as a “bipolar switch element”.

  Next, the definition of the electrodes in the bipolar variable resistance element will be described. Here, the electrode to which a positive voltage is applied when the switch element transitions from the OFF state to the ON state is a first electrode (or active electrode), and the other electrode is a second electrode (or inactive electrode).

  In the present embodiment, the variable resistance element is a bipolar element including a first electrode, an insulating film whose resistance value is changed by application of voltage or current, and a second electrode.

  As a result of examining the programming method of the variable resistance element, the inventors have found the following method. That is, the inventors have found a programming method that enables a stable operation at a low voltage and a low current by utilizing the fact that the voltage polarity is different between writing and erasing of a bipolar element.

  FIG. 3 is a diagram illustrating an example of a programming method according to the present embodiment and a conventional programming method. Referring to FIG. 3, for example, in order to change (write) the resistance change element from the OFF state to the ON state, in the present embodiment, the negative pulse voltage is applied as the first pulse voltage immediately before the second pulse voltage is applied. A positive pulse voltage is applied as the pulse voltage. That is, in this embodiment, after applying the pulse voltage in the direction opposite to the programming direction, the pulse voltage in the programming direction is applied.

  At this time, the resistance variation in the OFF state is suppressed and reduced by the application of the first pulse voltage, so that the transition from the OFF state to the ON state is stabilized. The fact that the resistance state does not transition from OFF to ON even when a negative pulse voltage is applied as the first pulse voltage in the OFF state is based on the characteristics of the bipolar variable resistance element.

  On the other hand, to change the resistance change element from the ON state to the OFF state (that is, to erase), after applying a positive pulse voltage as the first pulse voltage, a negative pulse voltage is applied as the second pulse voltage.

  At this time, mass transfer is facilitated by an amount corresponding to the temperature rise by causing local heat generation due to the flowing current by applying the first pulse, so that the resistance change element is switched from the ON state to the OFF state with a low current. Transition can be made.

  Hereinafter, the control method of the resistance change element according to the embodiment will be described in more detail in accordance with a specific example.

<Writing method>
As a first embodiment, a writing method of a resistance change element will be described. The resistance change element in the present embodiment is a bipolar element including a first electrode, an insulating film whose resistance value is changed by application of voltage or current, and a second electrode.

  FIG. 4 is a diagram illustrating an example of the configuration of the variable resistance element according to the present embodiment. Referring to FIG. 4, the variable resistance element includes a first electrode 110, a titanium oxide film 112, an ion conductive layer 113, and a second electrode 114. The first electrode 110 is made of a metal whose main component is copper (Cu). The ion conductive layer 113 includes, for example, silicon (Si), oxygen (O), and carbon (C) as materials. The second electrode 114 includes ruthenium (Ru).

  The titanium oxide film 112 is a film for suppressing oxidation of the first electrode 110 during the formation of the ion conductive layer 113 and functions as a valve metal. The oxidation of the lower first electrode (copper) can be suppressed by the valve metal oxide film. The standard free energy of a valve metal made of an oxide such as titanium (Ti) has a larger value on the negative side than copper. Therefore, the valve metal functions to absorb oxygen generated during the formation of the ion conductive layer, and forms a valve metal oxide film. Thereby, the oxidation of the first electrode is suppressed.

  The valve metal is a metal for preventing oxidation of copper. Besides titanium (Ti), aluminum (Al), tantalum (Ta), niobium (Nb), hafnium (Hf), zirconium (Zr), zinc (Zn) ), Tungsten (W), bismuth (Bi), antimony (Sb), or the like can be used.

The electrical characteristics in this example are as follows: the material of the first electrode 110 is Cu, the film thickness is 200 nm, the material of the ion conductive layer 113 is C ₇ O ₁ Si ₁ , the film thickness is 6 nm, This is a result obtained when the material of the electrode 114 is Ru and the film thickness is 20 nm.

  FIG. 5 is a block diagram showing an example of the configuration of the semiconductor device in this embodiment. Referring to FIG. 5, the semiconductor device includes a variable resistance element having a first electrode (active electrode) 110, an ion conductive layer 113 and a second electrode (inactive electrode) 114, and a programming transistor 115. . The first electrode 110 is connected to the drain terminal of the programming transistor 115, the source terminal of the programming transistor 115 is connected to the V1 terminal, and the second electrode 114 is connected to the V2 terminal.

  When a positive pulse voltage is applied to the variable resistance element, a voltage is applied to V 1, V 2 is grounded, and a voltage having a predetermined pulse width is applied to the gate terminal (Vg) of the programming transistor 115. On the other hand, when a negative pulse voltage is applied to the variable resistance element, V1 is grounded, a voltage is applied to V2, and a voltage having a predetermined pulse width is applied to the gate terminal (Vg) of the programming transistor 115.

  The current (ON current) that flows when transitioning from the OFF state to the ON state can be controlled by the driving force (saturation current) of the programming transistor 115. In this embodiment, an NMOS transistor in which a saturation current of 500 μA flows when Vg = 1 V is applied is used as the programming transistor 115.

  FIG. 6 shows a method (write method) for transitioning the variable resistance element from the OFF state to the ON state in this embodiment. Referring to FIG. 6, in order to stabilize the resistance value in the OFF state, a first pulse voltage (a negative pulse voltage of 2 V, 1 microsecond (μsec)) is applied. Next, a 10 nsec interval is provided, and a second pulse voltage (3 V, 10 nanosecond (nsec) positive pulse voltage) is applied.

  Since the application of the first pulse voltage suppresses and reduces the resistance variation in the OFF state, the transition from the OFF state to the ON state is stabilized. In this state, when a 1 kilobit (kbit) element was measured, the ON resistance variation was 1σ = 30%. On the other hand, the ON resistance variation when programming was performed without applying the first pulse voltage was 1σ = 40%. Therefore, according to the writing method of the present embodiment, it is possible to greatly reduce the ON resistance variation.

  Note that the resistance state does not transition from the OFF state to the ON state even when the first pulse voltage (negative pulse voltage) is applied in the OFF state, based on the characteristics of the bipolar variable resistance element.

  In addition, compared with the conventional programming method in which the first pulse voltage is not applied, the programming method of the present embodiment in which the first pulse voltage is applied has less variation in threshold voltage that causes a change in resistance state. It was confirmed that

  Furthermore, when the first pulse voltage was applied twice, it was found that the variation in threshold voltage can be further reduced as compared with the case where the first pulse voltage is applied once. However, as the number of times of application of the first pulse voltage is increased, the time required for programming one bit (bit) increases, so an appropriate number of times of application is selected while balancing between programming time and threshold variation. It is preferable to do.

<Erase method>
As a second embodiment, a method for erasing a resistance change element will be described. The semiconductor device of this embodiment has the same configuration as that of the semiconductor device of the first embodiment (FIG. 5).

  FIG. 7 shows a method (erase method) for transitioning the resistance change element from the ON state to the OFF state in this embodiment. Referring to FIG. 7, the first pulse voltage (0.2 V, 1 μsec positive pulse voltage) is applied to the variable resistance element in the ON state. At this time, since the ON resistance value of the variable resistance element was 200Ω, a current of about 1 mA flows through the variable resistance element over a period of 1 μsec. Next, a 10 nsec interval is provided, and a second pulse voltage (10 nsec negative pulse voltage) is applied.

  Here, the threshold voltage was evaluated by gradually increasing the voltage value of the negative pulse voltage. The temperature of the resistance change element rises due to the Joule heat of the current flowing by applying the first pulse voltage, and the resistance value can be easily changed even with a small current. In the conventional programming method in which the first pulse voltage is not applied, a voltage of 4 V is required to erase all bits of the 1 kbit element. On the other hand, according to the method of the present embodiment in which the first pulse voltage is applied, all bits can be erased by applying a voltage of 3.5V.

  Further, according to the conventional programming method, the peak current value necessary for erasing was 1 mA. On the other hand, according to the programming method of the present example, the peak current value could be reduced to 500 μA. Therefore, according to the present embodiment, the driving force of the programming transistor can be reduced, and the chip size can be reduced.

Furthermore, it has been found that the resistance state variation after the transition to the OFF state is reduced according to the programming method of the present embodiment in which the first pulse is applied, compared to the conventional programming method in which the first pulse is not applied. . According to the conventional method, 2% of bits with an OFF resistance value of 10 ⁷ Ω existed. On the other hand, according to the programming method of the present embodiment, all the bits were 10 ⁸ Ω or more.

  In addition, when the interval between the application of the first pulse voltage and the application of the second pulse is 10 nsec or more, the effect of applying the first pulse voltage is lost as the interval increases. It was found that the characteristics approached when only the second pulse voltage was applied.

  In the above embodiments and examples, the case where the ion conductive layer is used as the bipolar variable resistance layer has been described. However, the present invention is not limited to such a case. The resistance change element control method according to the present invention can be applied to any element as long as the element exhibits bipolar resistance change characteristics. For example, even in a ReRAM element using an oxide such as Ti, W, and Ni, the method of the present invention can be applied by appropriately selecting an electrode to realize a bipolar resistance change operation.

  Further, as a background of the invention, a semiconductor device having a CMOS circuit has been described, but the present invention is not limited to such a semiconductor device. For example, a semiconductor product having a memory circuit such as a DRAM (Dynamic RAM), an SRAM (Static RAM), a flash memory, an FRAM (Ferroelectric RAM), an MRAM (Magnetic RAM), a resistance change memory, a bipolar transistor, or the like, a microprocessor The present invention can also be applied to a semiconductor product having a logic circuit such as the above and a copper wiring of a board or package on which these are simultaneously mounted.

  Furthermore, the present invention can be applied to an electronic circuit device, an optical circuit device, a quantum circuit device, a micro machine, a MEMS (Micro Electro Mechanical Systems), a display device, and the like. In the above-described embodiments and examples, the description has focused on the switching function. However, the method of the present invention can also be applied to programming of a memory element using both non-volatility and resistance change characteristics.

  It should be noted that the disclosures of prior art documents such as the above patent documents are incorporated herein by reference. Within the scope of the entire disclosure (including claims) of the present invention, the embodiments and examples can be changed and adjusted based on the basic technical concept. Various combinations and selections of various disclosed elements are possible within the scope of the claims of the present invention. That is, the present invention of course includes various variations and modifications that could be made by those skilled in the art according to the entire disclosure including the claims and the technical idea.

110 First electrode 112 Titanium oxide film 113 Ion conduction layer (resistance change layer)
114 Second electrode 115 Programming transistor

Claims (9)

A resistance change layer that transitions between a first state and a second state having different resistance values according to the polarity of the applied pulse voltage; a first electrode connected to one end of the resistance change layer; A control method of a resistance change element including a second electrode connected to the other end,
A first pulse voltage having a second polarity opposite to a first polarity for causing the resistance change layer to transition from the first state to the second state is applied to the resistance change layer in the first state. Maintaining between the first electrode and the second electrode,
After applying the first pulse voltage, a second pulse voltage having the first polarity is applied between the first electrode and the second electrode, and the resistance change layer is moved to the first electrode. a step of transitioning to the second state from the first state, only including,
The variable resistance layer is an ion conductive layer containing at least silicon (Si), oxygen (O), and carbon (C), the first electrode contains copper (Cu), and the second electrode is ruthenium ( including ru), and wherein the control method of the variable resistance element.   After the first pulse voltage is applied between the first electrode and the second electrode at least twice, the second pulse voltage is applied between the first electrode and the second electrode. The resistance change element control method according to claim 1, wherein the resistance change element is applied to the resistance change element.   3. The resistance change element control method according to claim 1, wherein a pulse width of the second pulse voltage is wider than a pulse width of the first pulse voltage. 4.   4. The resistance change element control method according to claim 1, wherein an interval between the first pulse voltage and the second pulse voltage is 10 nsec (nanoseconds) or less. 5. .   The first state is an on state, the second state is an off state, and the first pulse voltage is 0.2 V or less and 1 μsec or less. 5. The method of controlling a resistance change element according to any one of 4 above.   When the first state is an on state, the second state is an off state, and the first pulse voltage is applied, the value of the current flowing through the resistance change element applies the second pulse. 6. The resistance change element control method according to claim 1, wherein the resistance change element is equal to or less than a current value flowing through the resistance change element.   When the first state is an on state, the second state is an off state, and the first pulse voltage is applied, the value of the current flowing through the resistance change element applies the second pulse. The resistance change element control method according to claim 1, wherein the resistance change element is equal to a current value flowing through the resistance change element.   The first state is an off state (high resistance state), the second state is an on state (low resistance state), and the first pulse voltage is 3 V or less and 10 μsec (microseconds) or less. The method of controlling a resistance change element according to any one of claims 1 to 4, wherein: A resistance change layer that transitions between a first state and a second state having different resistance values according to the polarity of the applied pulse voltage;
A first electrode connected to one end of the variable resistance layer;
A second electrode connected to the other end of the variable resistance layer;
A first pulse voltage having a second polarity opposite to a first polarity for causing the resistance change layer to transition from the first state to the second state is applied to the resistance change layer in the first state. The second pulse voltage having the first polarity is applied between the first electrode and the second electrode after being applied between the first electrode and the second electrode. And a programming circuit that causes the resistance change layer to transition from the first state to the second state.
The variable resistance layer is an ion conductive layer containing at least silicon (Si), oxygen (O), and carbon (C), the first electrode contains copper (Cu), and the second electrode is ruthenium ( Ru) . A semiconductor device comprising:

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