JP2021019090A - Non-volatile memory element and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-volatile memory element which is thermally stable, does not require melting at the time of electrical resistance switching, and does not require a forming process or setting of a current limit. A non-volatile memory element is composed of a Cr nitride film having a NaCl-type crystal structure, and has a memory layer (4) and a memory layer whose electrical resistance can be changed to a plurality of states different from each other by applying an electric pulse. It is provided with first and second electrodes (2, 5) for energizing. [Selection diagram] Fig. 5

Description

The present invention relates to a non-volatile memory device and a method for manufacturing the same.

In recent years, with the development of the IoT society and the ICT society, the amount of data traffic on the Internet around the world has increased rapidly, and the innovation of non-volatile memory for storing such data is strongly desired. Therefore, research and development of next-generation non-volatile memory that surpasses the performance of flash memory, which is currently the mainstream, is being carried out all over the world. Next-generation non-volatile memory includes ferroelectric memory (FeRAM: Ferroelectric Random Access Memory), magnetic resistance memory (MRAM: Magnetoresistive Random Access Memory), phase change memory (PCRAM: Phase Change Random Access Memory), and resistance change memory. Memory (ReRAM: Resistive Random Access Memory) and the like can be mentioned. Of these, PCRAM and ReRAM record information by sandwiching a specific material (information recording layer) between electrodes and utilizing the change in electrical resistance caused by the application of electrical pulses. Due to its simple memory element structure, PCRAM and ReRAM have many industrial merits such as low manufacturing cost and high integration (that is, large capacity), and they are used all over the world. Research and development is flourishing.

A material called a phase change material is used for the information recording (memory) layer of the PCRAM, and the PCRAM utilizes the change in electrical resistance accompanying the phase change between the crystalline phase and the amorphous phase of the phase change material to provide information. To record. For the phase change between the crystalline phase and the amorphous phase of the phase change material, Joule heating by an electric pulse is used. For example, an electric pulse is applied to the crystal phase, Joule heating is performed to a melting point of Tm or higher to melt the material, and then quenching is performed to obtain an amorphous phase. On the other hand, an electric pulse is applied to the amorphous phase to obtain a crystallization temperature of Tc or higher. Joule heating is performed to a melting point of less than Tm to obtain a crystalline phase. In general, the crystalline phase exhibits low electrical resistance and the amorphous phase exhibits high electrical resistance, so information can be recorded by assigning bits to these layers.

Currently, a Ge-Sb-Te-based chalcogenide compound (GST) used in DVD-RAM is used as a phase change material for PCRAM (see, for example, Non-Patent Documents 1 and 2).

On the other hand, ReRAM is a memory that does not need to melt the material. A transition metal oxide or a perovskite-type oxide is generally used for the memory layer of the ReRAM. Various mechanisms have been proposed for the resistance change mechanism, but basically it is caused by an increase or decrease in the loss of oxygen or metal atoms in the metal oxide near the electrode interface caused by applying a voltage or passing an electric current. It is said (see, for example, Non-Patent Document 3).

For example, in a Pt / Cu oxide / W element in which a Cu oxide is sandwiched between Pt and W and a Pt / Ti oxide / Pt element in which a Ti oxide is sandwiched between Pt, electricity between high electric resistance and low electric resistance Resistance switching characteristics have been obtained, and in particular, Ti oxide has stable repetitive characteristics (see, for example, Non-Patent Document 4).

In general, when these oxides are used as a memory element, a step (forming process) of forming an electric conduction path by applying a high voltage is indispensable after manufacturing the memory element. However, Patent Document 1 is a method for manufacturing a resistance-changing memory element composed of three layers of metal / metal oxide (resistance changing layer) / metal, and a substance having electrical conductivity is added to the metal oxide. A conductive path is formed through a substance that causes a resistance change, and a conductive prefilament is formed at the start of operation of the element without going through a high-voltage forming process of the conductive path by an additive material. Has been done.

In Patent Document 2, there are two or more states having different electric resistance values, and a resistance change that changes from one state selected from the two or more states to another state by applying a predetermined voltage or current. Described are those comprising a layer and the resistance changing layer containing first and second elements capable of forming a nitride and nitrogen.

Japanese Patent No. 5874905 Japanese Patent No. 4857014

N. Yamada et al. "Rapid-phase transitions of GeTe-Sb2Te3 pseudobinary amorphous thin films for an optical disk memory" J. Apple. Phys. 69 (5) (1991) p2849 Motoyasu Terao, "Phase Change Memory- (PRAM)" Applied Physics Vol. 75, No. 9 (2006) p1098 Supervised by Mitsumasa Koyanagi, "Latest Technology of Next-Generation Semiconductor Memory" Chapter 5 Latest Technology of ReRAM, CMC Publishing, 2009 Hiroshi Nishioka et al. "Research and Development on Ultra-Large Capacity Non-Volatile Memory Using Transition Metal Oxides and Their Microfabrication Process" ULVAC TECHNICAL JOURNAL No. 67 (2007) p1

Since Te, which is a chalcogen element contained in GST, is active in PCRAM, it is easy to form a compound, and a chemical reaction occurs between the memory layer and the electrode layer due to Joule heating, so that the rewriting operation durability is limited by segregation of material composition. Has the problem of Further, the phase change material represented by GST has a problem that the power consumption during operation is high because the material needs to be melted in order to increase the electric resistance, that is, to make it amorphous.

In the case of ReRAM, there is a practical concern that other semiconductor elements will be destroyed in the process of forming an electric conduction path by applying a high voltage. Further, in general, the information recording layer used for ReRAM is prevented from being destroyed by an excessive current due to a sudden resistance change when operating from a high electric resistance state to a low electric resistance state. There is also a practical problem that the current limit (compliance) must be set.

As described above, both PCRAM and ReRAM using the electric resistance change type memory element have some problems, and it is expected to create a memory element that solves these problems.

The present invention has been made for the purpose of improving the above-mentioned problems of the conventional non-volatile memory element, and an object of the present invention is to provide a non-volatile memory element having excellent practicality. That is, it is an object of the present invention to provide a non-volatile memory element that is thermally stable, does not require melting during electrical resistance switching, and does not require a forming process or setting of a current limit. ..

A memory layer composed of a Cr nitride film having a NaCl-type crystal structure and whose electrical resistance can change to a plurality of states different from each other by applying an electric pulse, and first and second electrodes for energizing the memory layer. A non-volatile memory element comprising the above is provided.

The composition ratio of Cr atoms and nitrogen atoms in the Cr nitride film is preferably 1: 1. The electric resistance value of the memory layer in the state where the electric resistance is relatively high among the plurality of states is more than twice the electric resistance value of the memory layer in the state where the electric resistance is relatively low among the plurality of states. Is preferable. A part of Cr atoms in the Cr nitride film is selected from at least Al, Si, Sc, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Hf, Ta and W. It may be substituted with one element.

By introducing nitrogen gas with a flow rate of 2 sccm or more and 6 sccm or less and performing reactive sputtering using a Cr target, it has a NaCl-type crystal structure and changes to multiple states with different electrical resistances by applying electric pulses. Provided is a method for manufacturing a non-volatile memory element, which includes a step of forming a possible Cr nitrided memory layer on a substrate and a step of forming first and second electrodes for energizing the memory layer.

Since the memory element of the present invention is thermally stable, it is unlikely to cause a chemical reaction at the electrode interface, and since it does not require melting, it operates with low energy, and the forming process and current limit setting are added. It is highly practical because it does not require a special process.

It is a table which shows the physical characteristic and the crystal structure of the Cr nitride film of various Examples and Comparative Examples. It is a schematic diagram of the crystal structure of a Cr nitride film. FIG. 4 is a diagram showing an X-ray diffraction pattern of a thin film of Example 4 as it is formed and heated to 500 ° C. and then cooled to room temperature. FIG. 1 is a diagram showing an X-ray diffraction pattern of a thin film of Comparative Example 1 as it is formed and heated to 500 ° C. and then cooled to room temperature. It is a schematic cross-sectional view and top view which shows the example of a memory element. It is a graph which shows the electric resistance change at the time of applying the electric pulse of 100ns to the memory element of FIG. It is a graph which shows the electric resistance change when the electric pulse of 20ns is applied to the memory element of FIG. It is a graph of the current-voltage curve when the current is swept with respect to the memory element of FIG.

As a result of studying conventional memory layer materials other than chalcogenides and oxides, the present inventors have formed a memory element by sandwiching a thermally stable Cr (chromium) nitride film between electrodes. Reversible electrical resistance switching characteristics between low electrical resistance states and high electrical resistance states can be obtained by applying electrical pulses without the need for melting and without forming processes or current limiting settings, and the resistance ratio is We have found that it reaches more than a single digit. This indicates that this memory element can have sufficient reliability for reading data. In the following, the low electric resistance state and the high electric resistance state are simply referred to as "low resistance state" and "high resistance state", respectively.

FIG. 1 is a table showing the physical characteristics and crystal structure of Cr nitride films of various examples and comparative examples. R ₁ shows the measured value of the electric resistance of the thin film sample as it is formed at room temperature, and R ₂ shows the measured value of the electric resistance of the thin film sample heated to 500 ° C. and then cooled to room temperature. .. In Figure 1, further shows with their electrical resistance ratio R _{2 /} R _1, the crystal structure in a state of being cooled to the heating room temperature after the state and 500 ° C. remain deposited.

The memory layer material of the present invention is a Cr nitride film, and as shown in FIG. 1, the electric resistance of the film as it is is lower than the electric resistance after heating to about 500 ° C. and then cooling to room temperature. Therefore, by arranging the first and second electrodes for energizing the Cr nitride film to form a memory element, a large change in electrical resistance can be obtained. Since it is preferable that the electric resistance of the memory layer changes more than twice for use as a memory element, in FIG. 1, a material in which the electric resistance in the high resistance state is more than twice as high as the electric resistance in the low resistance state is used. It was used as the memory layer material of the present invention. In Examples 1 to 5 of FIG. 1, the state in which the film is formed corresponds to the low resistance state, and the state after heating corresponds to the high resistance state. In the memory layer material of the present invention, the process of heating to 500 ° C. is equivalent to changing the Cr nitride film from a low resistance state to a high resistance state by Joule heating by applying an electric pulse.

FIG. 2 is a schematic view of the crystal structure of the Cr nitride film. As shown in FIG. 2, the Cr nitride film of the present invention has a NaCl-type crystal structure (NaCl structure). The NaCl structure is a structure in which a Na atom in a NaCl crystal is replaced with a Cr atom and a Cl atom is replaced with an N atom. That is, the Cr nitride film of the present invention is a film represented by the chemical formula of Cr—N and having a NaCl structure, and the composition ratio of chromium and nitrogen is 1: 1. Since FIG. 2 is a schematic diagram, the diameter of each atom and the size of the distance between the atoms shown in the figure are not always accurate.

Furthermore, the crystal structure of the Cr nitride film of the present invention hardly changes before and after the change in electrical resistance, and within a macro range that can be identified by a normal X-ray diffraction experiment, it is in a high resistance state or a low resistance state, that is, The structure is basically NaCl, whether it is formed or after heat treatment. However, since the electrical resistance changes, it is considered that the crystal structure is different between the high resistance state and the low resistance state when viewed extremely locally (for example, at the level of several atoms). Therefore, the Cr nitride film of the present invention has a NaCl structure in a low resistance state to which an electric pulse is not applied, and has a NaCl structure even when an electric pulse is applied to change to a high resistance state, but the crystal at that time. The structure has changed locally compared to the low resistance state.

The composition ratio of chromium and nitrogen in the Cr nitride film does not have to be exactly 1: 1 and may deviate slightly from 1: 1 as long as it has a NaCl structure in the macro range in the above sense. Further, the Cr nitride film may be one in which a part of Cr is replaced with another element X and is represented by (Cr, X) N. In this case, the composition ratio of (Cr + X): N is 1. It should be close to 1. Examples of other element X include Al (aluminum), Si (silicon), Sc (scandium), Ti (tungsten), V (vanadium), Mn (manganese), Fe (iron), Co (cobalt), Ni. (Nickel), Cu (copper), Zn (zinc), Y (yttrium), Zr (zirconium), Nb (niobium), Mo (molybdenum), Hf (hafnium), Ta (tantal), W (tungsten), etc. Can be mentioned. The other element X may be one or more elements selected from these groups, and preferably forms a stable nitride.

Examples of the method for producing the memory layer material of the present invention include a physical vapor deposition method (such as sputtering) and a chemical vapor deposition method (such as chemical vapor deposition). In the case of sputtering, the film is formed using a Cr target or a CrN target whose components have been adjusted in advance. When a Cr target is used, the desired Cr nitride film can be formed by performing reactive physical vapor deposition while adjusting the N ₂ (nitrogen) gas flow rate. The substrate temperature at the time of film formation can be changed from room temperature to 500 ° C. as needed.

In the thin films of Examples 1 to 5 and Comparative Examples 1 and 2 shown in FIG. 1, pure element Cr was used as a target, and an RF sputtering apparatus was used to use nitrogen gas together with argon gas as a sputtering gas. It was formed on the substrate by reactive sputtering film formation. The film thickness was 100 nm, and the nitrogen concentration was controlled by changing the nitrogen gas flow rate. This also contains impurities that are inevitably contained in the film-forming raw material. Usually, such unavoidable impurities are on the order of several ppm to several tens of ppm, and therefore do not have a great influence on physical characteristics such as electric resistance value after film formation. The Cr nitride films of Examples and Comparative Examples were prepared by a sputtering vapor deposition apparatus (MUE-201C-HC1) manufactured by ULVAC, vacuum exhausted until the base pressure became 2 × 10 ^-5 Pa or less, and then argon gas. The flow rate was fixed at 15 sccm, and the nitrogen gas flow rate was changed from 0.5 to 6 sccm. The film forming pressure at this time was in the range of 0.35 to 0.45 Pa. Further, the output of the Cr target at the time of film formation was fixed at 50 W.

The electrical resistance value in FIG. 1 is a general two-terminal system in which two W electrode needles are simply pressed from above on a Cr nitride film as it is formed or heated to 500 ° C. and then cooled to room temperature. Measured by method. The two-terminal measurement was performed at room temperature. The sample shape was 15 mm long and 5 mm wide, and the distance between the two terminals was 10 mm. The crystal structure of each Cr nitride film shown in FIG. 1 was evaluated by X-ray diffraction using Cu Kα.

As shown in FIG. 1, in each of the Cr nitride films in which nitrogen gas was formed in the range of 2 to 6 sccm in Examples 1 to 5, they were heated to 500 ° C. and then at room temperature with respect to the electrical resistance as they were formed. The electrical resistance after cooling to is more than doubled. On the other hand, in the Cr nitride film formed with nitrogen gas of 1.0 sccm or less in Comparative Examples 1 and 2, only a small electric resistance ratio of about 0.5 to 0.9 was obtained.

Even if the flow rate of nitrogen gas exceeds 6 sccm, plasma is generated in the sputtering vapor deposition apparatus, and as long as the sputtering can be performed, the electric resistance ratio R ₂ / R ₁ is the same as in Examples 1 to 5. It is expected to more than double. The number of nitrogen atoms that can be bonded to chromium atoms is limited, and even if a large amount of nitrogen gas is supplied, the excess is exhausted, so there is no upper limit to the flow rate of nitrogen gas during film formation. .. However, if the amount of nitrogen gas is too large, plasma during sputtering is not generated and film formation cannot be performed. Therefore, the upper limit of the range in which plasma is generated becomes the upper limit of the flow rate of nitrogen gas. The film forming conditions may change depending on the capacity of the film forming (depositing) device and the size of the chamber in the device, but when the film forming pressure is 0.01 Pa or less, plasma is less likely to be generated, and when the film forming pressure is 10 Pa or more. Even if plasma is generated, it is considered that the film formation rate becomes extremely slow and film formation becomes difficult. Therefore, the flow rate of the nitrogen gas is set so that the film forming pressure is between 0.01 and 10 Pa.

FIG. 3 is a diagram showing an X-ray diffraction pattern of a thin film of Example 4 as it is formed and heated to 500 ° C. and then cooled to room temperature. It can be seen that the film shows almost the same X-ray diffraction pattern after heating at 500 ° C. as it is, and exhibits a NaCl structure. When the crystal structure of each Cr nitride film shown in FIG. 1 was examined by X-ray diffraction, it was found that all of Examples 1 to 5 exhibited a NaCl structure. This suggests that the change in electrical resistance after heating is caused by a slight change in the local structure in the crystal structure.

FIG. 4 is a diagram showing an X-ray diffraction pattern of a thin film of Comparative Example 1 as it was formed and heated to 500 ° C. and then cooled to room temperature. The Cr nitride film of Comparative Example 1 has an amorphous structure in which no reflection peak is observed as it is formed, but after heating, it exhibits a structure in which a NaCl structure, a hexagonal structure and a body-centered cubic (bcc) structure are mixed. Was there. NaCl structure CrN phase, hexagonal structure Cr ₂ N phase, body-centered cubic structure is Cr phase.

As described above, when a phase having a structure other than the NaCl structure appears, the electric resistance ratio is small, and when the memory element is used, the electric resistance switching characteristic showing a large resistance change of one digit or more cannot be obtained. Therefore, the crystal structure of the Cr nitride film needs to be a NaCl structure.

Subsequently, the characteristics of the memory device using the Cr nitride film of the present invention will be described. In the memory element of the present invention, a memory layer of a Cr nitride film is sandwiched between electrode layers, or electrodes are formed at both ends of the memory layer, and they are usually formed on or in an insulating layer. The electrode material may be any conductive material, and examples thereof include W, TiN, TiW, Al, Ni, Pt, and Cu. The electrode may be any electrode that can energize the memory layer, and is not limited to a layered electrode that sandwiches the memory layer, and may be arranged above or to the side of the memory layer.

Usually, in a resistance change type memory such as PCRAM or ReRAM, an electric pulse is applied through an electrode layer to change the electric resistance. Further, the larger the electric resistance ratio obtained at that time, the better the data reading accuracy. In particular, with the increasing integration of memory, the miniaturization of the memory cell structure has become important. However, with the miniaturization, the total electric resistance of the memory element is not the electric resistance value of the memory layer itself, but the electrode layer /. It will be dominated by the contact resistance value between the memory layers.

5 (a) and 5 (b) are a schematic cross-sectional view and a top view showing an example of a memory element. The memory element shown in FIG. 5 was manufactured using the Cr nitride film of Example 4, and the electric resistance switching operation when an electric pulse was applied was investigated. In FIG. 5, reference numeral 1 is a SiO ₂ / Si substrate, 2 is a lower electrode layer formed on the substrate 1, 3 is an insulating (SiO ₂ ) layer formed on the electrode layer 2, and 4 is a Cr nitride of Example 4. A memory layer 5 formed of a film indicates an upper electrode layer formed on the memory layer 4, and 6 indicates a measurement probe. The electrode layers 2 and 5 were formed of W in this experiment. The film thickness of the electrode layer 2 is 50 nm, and the film thickness of the insulating layer 3 is 100 nm. In order to reduce the contact area between the electrode layer 2 and the memory layer 4 and reduce the electric power required for Joule heating, a hole having a diameter d = 150 nm was formed in the electrode layer 2 and the insulating layer 3 by using a focus ion beam. Then, a Cr nitride film was formed by a photolithography method and sputtering to form a memory layer 4 having a film thickness of 150 nm, and an electrode layer 5 (film thickness: 200 nm) was laminated on the memory layer 4.

FIG. 6 is a graph showing a change in electrical resistance when an electric pulse of 100 ns is applied to the memory element of FIG. The electric resistance after the application of the electric pulse was read at 0.1 V. The initial state was a state in which the Cr nitride film was formed, that is, a low resistance state, and the resistance value was 5.6 × 10 ³ Ω. There, where the pulse width is applied a voltage of 1.1V at 100 ns, the electric resistance increased rapidly to 1.2 × 10 ⁵ Ω. Thereafter, the maximum increasing the voltage, the electric resistance was increased to 5.2 × 10 ⁶ Ω. On the other hand, when an electric pulse of 2.4 V was applied, it was found that the electric resistance sharply decreased to 9.2 × 10 ³ Ω. This value is about the same as the initial state. In this way, by applying the electric pulse, a reversible and large change in electric resistance can be obtained. This large electrical resistance is due to the change in electrical resistance due to the change in the local structure of the memory layer and the accompanying change in contact resistance between the memory layer / electrode layer.

FIG. 7 is a graph showing a change in electrical resistance when an electric pulse of 20 ns is applied to the memory element of FIG. The electric resistance after the application of the electric pulse was read at 0.1 V. The initial state is a high resistance state obtained by applying a voltage of 1.5 V with a pulse width of 100 ns to the Cr nitride film (low resistance state) as it is formed, and the resistance value of the high resistance state is 3. It was 9 × 10 ⁶ Ω. When a voltage of 3.9 V was applied to the pulse width of 20 ns, the electrical resistance dropped sharply to 3.6 × 10 ³ Ω. Thereafter, by applying the electric pulse of 5.3V, the electric resistance increases rapidly to 8.0 × 10 ⁶ Ω, returned to the electric resistance and comparable values of approximately the initial state.

As described above, in the memory element of the present invention, unlike PCRAM, it is not necessary to melt the material of the memory layer, and information is written by applying an electric pulse without the forming process generally required for ReRAM. -It was confirmed that erasure is possible.

For example, in the example of FIG. 6 in which an electric pulse of 100 ns is applied, the memory layer changes to a high resistance state when a voltage (set voltage) of 1.1 V or more and less than 2.4 V is applied in the low resistance state. However, when a voltage of 2.4 V or higher (reset voltage) is applied in the high resistance state, the resistance changes to the low resistance state, and these states continue even if the application is stopped. Therefore, in order to write information to the memory element or erase it, a voltage of 1.1 to 2.4 V or 2.4 V or more may be applied to change the resistance state of the memory layer. In order to read the information recorded in the memory element, a voltage of 0.1 V or more and less than 1.1 V may be applied to detect the high or low resistance value of the memory layer. The above voltage value range is an example, and changes depending on the contact area between the memory layer and the electrode, the thickness of the memory layer, the composition, and the like.

When the voltage is increased, the resistance state changes in the order of low, high, and low in the case of FIG. 6, and the resistance state changes in the order of high, low, and high in the case of FIG. This is because the states are opposite to each other. As shown in FIGS. 6 and 7, the voltage range in which the resistance state changes also changes depending on the pulse width (frequency) of the applied voltage. Therefore, the memory element and the electric pulse used for recording and reading information are used. The voltage range may be adjusted as appropriate according to the above.

FIG. 8 is a graph of a current-voltage curve when a current is swept from the memory element of FIG. By sweeping a pulse current of 500 μs from 0 to 45 μA and then removing the current to 0 A again, the electrical resistance switching behavior from the high resistance state to the low resistance state was confirmed. When the current is swept, it can be seen that when the threshold voltage reaches 2.5 V, the high resistance state is switched to the low resistance state. As described above, it can be seen that the change from the high resistance state to the low resistance state is possible without setting the current limit generally required in the ReRAM.

In the Cr nitride film of the present invention, the electrical resistance after heating to about 500 ° C. and then cooling to room temperature becomes higher than the original electrical resistance before heating and cooling, and the change in electrical resistance is in the NaCl type crystal state. Occurs. Further, by joining an electrode layer for energizing the Cr nitride film, a large electric resistance switching characteristic of one digit or more can be obtained by applying an electric pulse. Further, the memory element of the present invention has high thermal stability, does not require melting of the material, can obtain a reversible and large electric resistance ratio, and further performs additional processes such as forming process and setting of current limit. It has the advantage of not needing it.

It should be noted that the present invention is not limited to the above examples, and naturally includes other examples, embodiments, etc. within the scope of the technical idea of the present invention.

The memory element of the present invention can be used for a non-volatile semiconductor memory having excellent long-term repeatability and low power consumption.

1 SiO ₂ / Si substrate 2 Lower electrode layer 3 Insulation layer 4 Memory layer 5 Upper electrode layer

Claims (5)

A memory layer composed of a Cr nitride film having a NaCl-type crystal structure and whose electrical resistance can change to a plurality of states different from each other by applying an electric pulse.
The first and second electrodes for energizing the memory layer,
A non-volatile memory element comprising. The non-volatile memory device according to claim 1, wherein the composition ratio of Cr atoms and nitrogen atoms in the Cr nitride film is 1: 1. The electric resistance value of the memory layer in the state where the electric resistance is relatively high among the plurality of states is 2 of the electric resistance value of the memory layer in the state where the electric resistance is relatively low among the plurality of states. The non-volatile memory element according to claim 1 or 2, which is more than double. Some of the Cr atoms in the Cr nitride film are selected from Al, Si, Sc, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Hf, Ta and W. The non-volatile memory element according to claim 1, wherein the non-volatile memory element is substituted with at least one element. By introducing nitrogen gas with a flow rate of 2 sccm or more and 6 sccm or less and performing reactive sputtering using a Cr target, it has a NaCl-type crystal structure and changes to multiple states with different electrical resistances by applying electric pulses. The process of forming a possible Cr nitrided memory layer on the substrate,
A step of forming the first and second electrodes for energizing the memory layer, and
A method for manufacturing a non-volatile memory element, which comprises.

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