JP2022107072A - Variable resistance device and manufacturing method for the same - Google Patents

Abstract

To provide a new variable resistance device with a variable resistance state.SOLUTION: One typical variable resistance device of the present invention includes an organic film and first and second electrodes at least portions of which are opposing each other with both sides of the organic film interposed therebetween. The organic film is characterized by the following: (1) the organic film includes π-type organic molecules having redox activity; (2) the π-type organic molecules exhibit π-π stacking in the stacking direction of the organic film; and (3) the π-type organic molecules exhibit anisotropic orientation. For example, a suitable example of such a π-type organic molecule is 2,5,8-tri(4-pyridyl)1,3-diazaphenalene ("aniso-TPDAP"), which exhibits anisotropic orientation.SELECTED DRAWING: Figure 1

Description

The present invention relates to a variable resistance device and a method for manufacturing the same.

As a next-generation memory, a non-volatile variable resistance memory is known.
As such a variable resistance memory, a device that utilizes the formation and erasure of a filament of a metal oxide is known.

Further, as a variable resistance memory, an organic ferroelectric memory using a ferroelectric organic substance is also known.

Further, as a variable resistance type memory, an organic memory having a floating gate structure is also known.

Further, in Patent Document 1, "a non-volatile storage device having a storage layer of a polyimide film in which chargeable fine particles are dispersed between a first conductive portion and a second conductive portion" is provided as a variable resistance memory. Will be disclosed.

Japanese Unexamined Patent Publication No. 2014-027185

In such a variable resistance memory, further improvement is desired from the viewpoint of high integration, durability, or atmospheric stability.

Therefore, an object of the present invention is to provide a new variable resistance device in which the resistance state is variable.

In order to solve the above problems, one of the representative variable resistance devices of the present invention includes an organic film and a first electrode and a second electrode at least partially facing each other with both sides of the organic film interposed therebetween. This organic film contains (1) π-type organic molecules having redox activity, (2) π-type organic molecules are in a state of π-π stacking in the stacking direction of the organic film, and (3) π-type organic molecules. Is an anisotropic orientation.

INDUSTRIAL APPLICABILITY The present invention provides a resistance variable device including an organic film having a variable resistance state.
Other issues, configurations and effects will be clarified by the description of the following embodiments.

FIG. 1 is a schematic view showing the structure of the variable resistance device 10 of the first embodiment. FIG. 2 is a diagram showing a general formula of a π-type organic molecule contained in the organic film 13. FIG. 3 is a schematic diagram illustrating the redox activity of 1,3-diazaphenalenyl. FIG. 4 is a diagram showing the molecular structure of 2,5,8-tri (4-pyridyl) 1,3-diazaphenalene, which is TPDAP. FIG. 5 is a diagram showing an intramolecular network of TPDAP in the plane direction of the organic film 13. FIG. 6 is a diagram showing a state of TPDAP in the stacking direction of the organic film 13. FIG. 7 is a diagram illustrating a method of forming an organic film 13 using TPDAP as a film material. FIG. 8 is a diagram showing the characteristics of the organic film 13 formed at the formation temperature Ts = 80 ° C. FIG. 9 is a diagram showing the characteristics of the organic film 13 formed at the formation temperature Ts = 25 ° C. FIG. 10 is a diagram showing a difference in electrical characteristics depending on the orientation state of the organic film 13. FIG. 11 is a diagram illustrating the basic operation of the variable resistance device 10. FIG. 12 is a diagram showing the insulation characteristics of the anisotropic organic film 13 (aniso-TPDAP) in the plane direction. FIG. 13 is a diagram showing the change over time in the non-volatility of the anisotropic organic film 13 (aniso-TPDAP). FIG. 14 is a diagram showing the durability of rewriting of the anisotropic organic film 13 (aniso-TPDAP). FIG. 15 is a diagram showing the atmospheric stability of the anisotropic organic membrane 13 (aniso-TPDAP). FIG. 16 is a diagram showing an example of voltage distribution when the variable resistance device 10 is used as a memory integrated device. FIG. 17 is a diagram illustrating the organic field effect transistor 300 of the second embodiment.

Hereinafter, examples will be described with reference to the drawings.

<< Structure of variable resistance device 10 >>
FIG. 1 is a schematic view showing the structure of the variable resistance device 10 of the first embodiment.

In the figure, the variable resistance device 10 includes a substrate 11, a first electrode 12, an organic film 13, and a plurality of second electrodes 14.

The substrate 11 is composed of, for example, a silicon substrate Si and an insulating layer SiO ₂ formed by oxidizing the surface thereof.

The first electrode 12 is formed on the surface of the insulating layer SiO ₂ using, for example, gold Au as an electrode material.

In the following, with respect to the organic film 13, the two-dimensional direction in which the film spreads is referred to as the "plane direction", and the direction of the film thickness of the organic film 13 is referred to as the "lamination direction".

The organic film 13 is formed on the surface of the first electrode 12 and has the following characteristics.
(1) The organic film 13 contains a π-type organic molecule having redox activity.
(2) The π-type organic molecule is in a π-π stacking state in the stacking direction of the organic film 13.
(3) The π-type organic molecule contained in the organic film 13 exhibits an anisotropic orientation.

Here, the state of π-π stacking means a state in which π-type organic molecules are self-aligned along the stacking direction due to intramolecular interaction due to π-π stacking. For example, it means both a state in which at least two aromatic rings of aromatic organic molecules are arranged so as to overlap each other, or a state in which at least two aromatic rings are arranged so as to be slightly offset from each other.

The anisotropic orientation means a state in which the π-type organic molecules contained in the organic film 13 or their crystals are aligned.

The plurality of second electrodes 14 are formed on the surface of the organic film 13 according to the arrangement pattern of predetermined variable resistance cells (memory cells) using, for example, gold Au as an electrode material.

In the variable resistance device 10 having such a configuration, a common voltage Vo is applied to the first electrode 12 individually by a circuit (not shown) and a wiring pattern (not shown) for data recording, data erasing, and data reading. A controlled control voltage Vx is applied to each of the plurality of second electrodes 14.

By satisfying the above conditions of redox activity, anisotropic orientation, and π-π stacking, π-type organic molecules are self-aligned in atomic units in the stacking direction of the organic film 13 to generate a current (carrier). A propagation path is formed. It is considered that resistance changes (high conduction state / low conduction state) occur in the stacking direction of the organic film 13 by introducing carriers or discharging carriers by oxidizing and reducing the inside of the propagation path.

<< Explanation of π-type organic molecules >>
Next, the π-type organic molecule will be described.

FIG. 2 is a diagram showing a general formula of a π-type organic molecule contained in the organic film 13.
At the center of the general formula of this π-type organic molecule is 1,3-diazaphenalenyl, which is composed of three rings and has a π-electron conjugated system.

FIG. 3 is a schematic diagram illustrating the redox activity of 1,3-diazaphenalenyl.
As shown in the figure, the π-type organic molecule based on 1,3-diazaphenalenyl has redox activity.

Furthermore, this 1,3-diazaphenalenyl has a functional group that becomes an acceptor (N) and a proton donor (NH) at the 1,3 position.

Due to this structure, the π-type organic molecule has proton transfer ability and electron donor property in addition to redox activity.

In addition, 1,3-diazaphenalenyl is characterized by forming hydrogen bonds between molecules, which makes it possible to construct an integrated intermolecular network.

Y1, Y2, and Y3 are arranged at the 2, 5, and 8 positions of the 1,3-diazaphenalenyl, respectively.

Each of Y1 to Y3 is a saturated or unsaturated hydrocarbon group having 1 to 60 carbon atoms, and these hydrocarbon groups may have one or more substituents. Further, one or more carbon atoms among these hydrocarbon groups are an oxygen atom, a sulfur atom, a silicon atom, and -NR- (where R is a hydrogen atom and an alkyl group having 1 to 10 carbon atoms. , Or an aryl group having 6 to 30 carbon atoms), −NR2, an aromatic group, a hydroxyl group, or a carboxylic acid. In addition, these Y1 to Y3 may be the same or different.

<< Explanation of TPDAP >>
Subsequently, TPDAP will be described as a representative example of the π-type organic molecule.

FIG. 4 is a diagram showing the molecular structure of 2,5,8-tri (4-pyridyl) 1,3-diazaphenalene called TPDAP.
In the figure, 4-pyridyl is arranged as Y1 to Y3 at the 2, 5 and 8 positions of 1,3-diazaphenalenyl, respectively.

FIG. 5 is a diagram showing an intramolecular network of TPDAP in the plane direction of the organic film 13.

As shown in the figure, hydrogen bonds of H ... N due to NH ... N type and CH ... N type act in the plane direction of the molecule of TPDAP to form a densely integrated network.

FIG. 6 is a diagram showing a state of TPDAP in the stacking direction of the organic film 13.
As shown in the figure, in the crystal of TPDAP, the atoms constituting the molecule are self-aligned in the stacking direction by the action of π-π stacking, so that they are densely stacked. By self-aligning in the stacking direction and densely stacking in this way, a current (carrier) propagation path can be formed in the stacking direction.

An example of such a method for generating TPDAP is given in the following document.

Jin Young Koo et al., "Redox-active Diazaphenalenyl-based Molecule and Neutral Radical Formation", The Chemical Society of Japan, Chem. Lett. 2015, 44, pp. 1131-1133

<< Method of forming the organic film 13 >>
Next, the film formation of the organic film 13 in Example 1 will be described.

FIG. 7 is a diagram illustrating a method of forming an organic film 13 using TPDAP as a film material.
In the figure, the vapor deposition apparatus 201 includes a high vacuum pump 202, a filament boat 204 on which a sample 203 of TPDAP is arranged, and a holder 205 on which a substrate 11 is arranged.

The high vacuum pump 202 transitions the inside of the vapor deposition apparatus 201 to a vacuum level of, for example, about 1E-6 Torr.

In this state, the filament boat 204 heats the sample 203 of TPDAP to, for example, about 230 ° C. and evaporates it.

The vaporized TPDAP crystals are vapor-deposited on the surface of the substrate 11 to form an organic film 13.

In this case, the film thickness of the organic film 13 is set by adjusting the evaporation density and the vapor deposition time.

Further, by setting the temperature of the substrate 11 via the holder 205 and adjusting the formation temperature Ts of the organic film 13, the orientation of the crystals and molecules of the organic film 13 can be controlled.
Here, two examples of the formation temperature Ts = 80 ° C and the formation temperature Ts = 25 ° C will be described.

The upper part [A] of FIG. 8 shows a two-dimensional pattern obtained by actually measuring micro-angle incident wide-angle X-ray scattering (hereinafter, also referred to as “GIWAXS”) for the organic film 13 formed under the condition of formation temperature Ts = 80 ° C. It is a figure.

Under the condition of the formation temperature Ts = 80 ° C, X-rays are scattered at a wide angle in the two-dimensional pattern of GIWAXS. Therefore, as schematically shown in the lower part [B] of FIG. 8, the orientation of the organic film 13 is , It is recognized that it shows isotropicity that is not aligned in the stacking direction.

On the other hand, the upper part [A] of FIG. 9 is a diagram showing a two-dimensional pattern in which micro-angle incident wide-angle X-ray scattering is actually measured for the organic film 13 formed under the condition of formation temperature Ts = 25 ° C.

Under the condition of the formation temperature Ts = 25 ° C, the scattering of X-rays is small in the two-dimensional pattern of GIWAXS. Therefore, as schematically shown in the lower part [B] of FIG. 9, the orientation of the organic film 13 is the stacking direction. It is recognized that it shows anisotropy aligned with. Inside the organic film 13 exhibiting this anisotropic orientation, the action of π-π stacking in the stacking direction is synergistic, and the atoms constituting the TPDAP molecule are self-aligned in the stacking direction.

In this way, the anisotropic orientation can be controlled by the formation temperature of the organic film 13.

<< Difference in electrical characteristics of organic film 13 depending on orientation state >>
Subsequently, the difference in the electrical characteristics of the organic film 13 depending on the orientation state will be described.

The upper part [A] of FIG. 10 shows the results of measuring the voltage-current characteristics in the stacking direction of the organic film 13 showing an isotropic orientation. As shown in the figure, in the isotropic organic film 13, a discontinuous critical change does not occur in the voltage-current characteristics in the stacking direction.

On the other hand, the upper part [B] of FIG. 10 shows the results of measuring the voltage-current characteristics in the stacking direction of the organic film 13 showing an anisotropic orientation. The horizontal axis of the figure shows the voltage value applied in the stacking direction of the organic film 13, and the vertical axis of the figure shows the magnitude (absolute value) of the current flowing in the stacking direction of the organic film 13. As shown in the figure, a discontinuous critical change occurs in the voltage-current characteristics in the stacking direction only in the anisotropic organic film 13.

<< Basic operation of variable resistance device 10 >>
Since the variable resistance device 10 applies a voltage to the anisotropic organic film 13 in the stacking direction by the first electrode 12 and the second electrode 14, the variable resistance device 10 operates according to the voltage-current characteristics shown in FIG. 10 [B].

FIG. 11 is a diagram illustrating the basic operation of the variable resistance device 10.

In the figure, the horizontal axis indicates the voltage difference (Vx-Vo) between the second electrode 14 and the first electrode 12. The vertical axis indicates the magnitude (absolute value) of the current flowing between the second electrode 14 and the first electrode 12 via the stacking direction of the organic film 13.

In the initial electrical state of the variable resistance device 10, only a weak leakage current of about 1 nanoampere flows with respect to the application of a voltage difference (Vx-Vo) = 0.5 [V], indicating a low conduction state. ..

This low conduction state has a non-volatile property because it can be reproduced regardless of whether the first electrode 12 and the second electrode 14 are electrically short-circuited or opened.

In this low conduction state, when a turn-on voltage (about 3V in FIG. 11) is applied between the second electrode 14 and the first electrode 12, a discontinuous critical change occurs in the voltage-current characteristics, and the state shifts to the high conduction state. do.

In this high conduction state, a current of about 1 milliamperes flows with respect to the application of a voltage difference (Vx-Vo) = 0.5 [V].

This high conduction state also has a non-volatile property because it can be reproduced regardless of whether the first electrode 12 and the second electrode 14 are electrically short-circuited or opened.

In this high conduction state, when a turn-off voltage (about -1.5V in FIG. 11) is applied between the second electrode 14 and the first electrode 12, a discontinuous critical change occurs in the voltage-current characteristics, resulting in low conduction. Return to the state.

In this case, the resistance ratio between the low conduction state and the high conduction state shows a large on-off resistance ratio of about "10 to the 6th power".

In this way, the variable resistance device 10 repeats the state transition through the cycle orbits of the low conduction state and the high conduction state along the direction of the arrow shown in FIG.

The above-mentioned turn-on voltage and turn-off voltage change depending on the film thickness of the organic film 13. Therefore, by thinning the organic film 13, the drive voltage of the variable resistance device 10 can be reduced. Further, by thickening the organic film 13, it becomes possible to expand the voltage range in which the variable resistance device 10 can be used as a resistor, a switch, or a recording medium.

<< Insulation characteristics of the organic film 13 in the plane direction >>
Subsequently, the insulating characteristics in the plane direction of the anisotropic organic film 13 will be described.

FIG. 12 is a diagram showing the results of measuring the voltage-current characteristics of the anisotropic organic film 13 (aniso-TPDAP) in the plane direction. The anisotropic organic film 13 causes only a very weak leakage current to flow in the plane direction, and exhibits excellent insulation characteristics.

As described above, since the organic film 13 itself has the insulating property in the plane direction, it is located in the adjacent boundary region (gap in the arrangement of the second electrode 14 shown in FIG. 1) of the variable resistance cell (memory cell) of the variable resistance device 10. Does not need to be separately provided with an insulating structure for electrically isolating it from the surroundings. Therefore, the variable resistance device 10 can be configured with a simple basic structure as shown in FIG.

As a result, the variable resistance cell (memory cell) can be easily miniaturized and highly integrated. In particular, considering that aniso-TPDP can function independently for each row of molecules aligned in the stacking direction, in principle, the area of the second electrode 14 of the variable resistance cell (memory cell) is on the order of the molecular size. It becomes possible to make it finer and highly integrated.

<< Non-volatile stability over time >>
FIG. 13 is a diagram showing the results of measuring the non-volatile stability over time of the anisotropic organic film 13 (aniso-TPDAP).

As shown in the figure, no noticeable change in the amount of current was observed in the measured time range in both the low conduction state and the high conduction state, and the non-volatility of the variable resistance device 10 was well maintained. There is.

<< Durability of rewriting >>
FIG. 14 is a diagram showing the results of measuring the rewriting durability of the anisotropic organic film 13 (aniso-TPDAP).

As shown in the figure, in both the low conduction state and the high conduction state, no noticeable change was observed in the amount of current within the measured number of times of rewriting, and even if rewriting (turn-on and turn-off) was repeated, even if rewriting (turn-on and turn-off) was repeated, The durability of the variable resistance device 10 is well maintained.

<< Atmospheric stability of variable resistance device 10 >>
FIG. 15 is a diagram showing the results of measuring the atmospheric stability under water vapor by repeatedly exposing the organic film 13 (aniso-TPDAP) to nitrogen gas containing water vapor.

As shown in the figure, there is no noticeable change in the amount of current flowing through the organic film 13 regardless of the presence or absence of nitrogen gas containing water vapor. Therefore, the variable resistance device 10 exhibits high atmospheric stability under water vapor.

Such a result is because the intermolecular network of the organic membrane 13 (aniso-TPDP) has a highly packed structure, so that the space for the external molecules to enter is small, and the molecules in the air do not easily penetrate the inside of the organic membrane 13. Conceivable.

Further, it is also considered that each region forming the variable resistance cell (memory cell) in the organic film 13 is substantially covered with the second electrode 14. Even if molecules in the air enter the inside of the organic film 13 (aniso-TPDAP) through the gaps in the arrangement of the second electrodes 14, they are variable due to the insulation characteristics of the organic film 13 (aniso-TPDAP) itself in the plane direction. It is also considered that this is because it does not easily affect the electrical characteristics of the resistance cell (memory cell).

Due to such atmospheric stability, the organic membrane 13 (aniso-TPDAP) is less likely to be contaminated by molecules in the air during the manufacturing process of the device, so that the air cleaning level at the time of manufacturing the variable resistance device 10 can be lowered. There are practical advantages such as high yield.

<< Use of variable resistance device 10 as a memory integrated device >>
FIG. 16 is a diagram showing an example of voltage distribution when the variable resistance device 10 is used as a memory integrated device.

As shown in the figure, a common voltage Vo = 1.75 [V] is applied to the first electrode 12.

At the time of reading the memory, the control voltage Vx = 2.25 [V] is applied to the second electrode 14. In this state, a read voltage of Vx—Vo = 0.5 [V] is applied in the stacking direction of the organic film 13. At this time, the storage data (high conduction state / low conduction state) of the memory cell is read out by detecting the current flowing through the memory cell covered by the second electrode 14 and making a binary determination.

Further, when the memory is set (written), the control voltage Vx = 4.75 [V] is applied to the second electrode 14. In this state, a turn-on voltage of Vx—Vo = 3.0 [V] is applied in the stacking direction of the organic film 13. At this time, the memory cell covered by the second electrode 14 non-volatilely shifts to the high conduction state, and the storage data of the memory cell is set.

On the other hand, when the memory is reset (erased), the control voltage Vx = 0.25 [V] is applied to the second electrode 14. In this state, a turn-off voltage of Vx−Vo = −1.5 [V] is applied in the stacking direction of the organic film 13. At this time, the memory cell covered by the second electrode 14 non-volatilely shifts to the low conduction state, and the stored data of the memory cell is reset.

<< Use of variable resistance device 10 as a switching device >>
The variable resistance device 10 shown in FIG. 1 can also be used as a switching device. In this case, by applying a voltage or current between the first electrode 12 and the second electrode 14 within a range not exceeding the turn-on voltage and the turn-off voltage, the high conduction state of the organic film 13 is utilized as the switch ON state, and the organic film 13 is organic. The low conduction state of the film 13 is used as the switch OFF state.

By the way, if you want to lower the ON resistance in the switch ON state or increase the absolute rated value of the ON current, adjust by connecting a plurality of second electrodes 14 in parallel or expanding the electrode area of the second electrode 14. Is possible.

In the second embodiment, an embodiment in which the variable resistance device is applied to a transistor will be described.
The upper part [A] of FIG. 17 is a schematic view showing the configuration of the organic field effect transistor 300.

In the figure, the organic field effect transistor 300 includes a gate G made of an N-type Si layer, an insulating layer 302 made of SiO ₂ , a graphene 303 capable of forming a channel path as a first electrode, and aniso-TPDAP. A film 304 and a drain D and a source S as a second electrode made of a gold Au pattern are provided on the upper surface of the organic film 304.

Since the organic film 304 is the same as the organic film 13 of Example 1, the duplicate description here will be omitted.

The gate G and the insulating layer 302 function as a gate mechanism for controlling the channel path of the graphene 303.

On the other hand, a voltage Vds is applied between the drain D and the source S.
In this state, when a voltage is applied to the gate G to change the channel path of the graphene 303 in the open direction, the equivalent resistance in the plane direction of the graphene 303 decreases.

Therefore, within the voltage Vds applied between the drain D and the source S, the voltage divided by the graphene 303 decreases.

Due to this action, in the series path to which the voltage Vds is applied, the voltage divided in the stacking direction of the organic film 304 rises and exceeds the turn-on voltage of the organic film 304. As a result, the stacking direction of the organic film 304 in contact with either the drain D or the source S turns on.

Then, the voltage Vds is intensively applied in the stacking direction of the organic film 304 in contact with the drain D or the other of the source S, and exceeds the turn-on voltage of the organic film 304. As a result, the stacking direction of the organic film 304 in contact with the drain D or the other of the source S is also turned on.

In this way, the stacking directions of the organic films 304 in contact with both the drain D and the source S are both turned on. In this state, the channel of graphene 303 can be controlled by the applied voltage of the gate G to control the drain current flowing through the drain D.

The middle stage [B] of FIG. 17 is a diagram showing the characteristics of the gate voltage-drain current of the organic field effect transistor 300.

Due to the organic film 304 in the turn-off state, almost no drain current flows immediately before the threshold voltage (about 12 V) of the gate voltage. However, when the gate voltage exceeds the threshold voltage and the organic film 304 is turned on, the drain current rapidly increases by about (10 to the 6th power) times.

In general, organic field effect transistors that use graphene in the channel path have a low on-off current ratio. However, by adding the organic film 304 containing aniso-TPDAP as the current barrier layer in the stacking direction, the on-off current ratio can be increased to about (10 to the 6th power) times.

The device configuration in the lower part [C] of FIG. 17 will be described later.

<< Supplementary matters of the embodiment >>
In Examples 1 and 2, the organic film 13 is formed by a vapor deposition method. However, the present invention is not limited to this. For example, the π-type organic molecule may be dissolved in a solvent and dropped or applied to the substrate 11 as a solution, and the film thickness of the organic film 13 may be controlled by the solution concentration, centrifugal force, or the like. Here, the solvent refers to, for example, a general organic solvent, and is not limited as long as it dissolves a π-type organic molecule.

Further, in Examples 1 and 2, the high conduction state or the low conduction state is stored as data by applying a read voltage between the first electrode 12 and the second electrode 14 within a range not exceeding the turn-on voltage and the turn-off voltage. Is read as. However, the present invention is not limited to this. For example, the high conduction state or the low conduction state may be read out as stored data by passing a read current between the first electrode 12 and the second electrode 14 within a range not exceeding the turn-on voltage and the turn-off voltage.

Further, in Examples 1 and 2, the variable resistance device is used as an integrated element by providing a plurality of second electrodes 14. However, the present invention is not limited to this. By providing only one pair of the first electrode and the second electrode, the variable resistance device may be a single element.

In Example 2, the organic film 304 is provided under the drain D and the source S. However, the present invention is not limited to this. For example, the organic film 304 under one of the drain D and the source S may be omitted (see the lower part [C] of FIG. 17). Even in such a configuration, since the organic film 304 under the other of the drain D and the source S functions as a current barrier, it is possible to obtain an organic field effect transistor having a high on / off current ratio.

10 ... variable resistance device, 11 ... substrate, 12 ... first electrode, 13 ... organic film, 14 ... second electrode, 201 ... vapor deposition equipment, 202 ... high vacuum pump, 203 ... sample, 204 ... filament boat, 205 ... holding Ingredients, 300 ... Organic field effect transistor, 302 ... Insulation layer, 303 ... Graphene, 304 ... Organic film, D ... Drain, G ... Gate, S ... Source

Claims (10)

It is provided with an organic film and a first electrode and a second electrode that at least partially face each other with both sides of the organic film interposed therebetween.
The organic film is
(1) Contains π-type organic molecules having redox activity
(2) The π-type organic molecule is in a state of π-π stacking in the stacking direction of the organic film.
(3) The π-type organic molecule inside the organic film has an anisotropic orientation.
A variable resistance device characterized by that. In the variable resistance device according to claim 1,
The π-type organic molecule is represented by the following general formula.

However, Y1 to Y3 in the formula may be the same or different, and independently represent saturated or unsaturated hydrocarbon groups having 1 to 60 carbon atoms, and the number of the hydrocarbon groups is one or two. It may have the above substituents, and one or more carbon atoms in the hydrocarbon group are oxygen atom, sulfur atom, silicon atom, -NR- (where R is hydrogen). It may be substituted with an atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 30 carbon atoms), -NR2, an aromatic group, a hydroxyl group, or a carboxylic acid.
A variable resistance device characterized by that. In the variable resistance device according to any one of claims 1 or 2.
A variable resistance device characterized in that H ... N hydrogen bonds are provided between the molecules of the π-type organic molecules arranged in the plane direction of the organic film. The variable resistance device according to any one of claims 1 to 3.
By temporarily applying a turn-on voltage between the first electrode and the second electrode, the stacking direction of the organic film is changed from a low conduction state to a high conduction state.
By once applying a turn-off voltage in the direction opposite to the turn-on voltage between the first electrode and the second electrode, the stacking direction of the organic film is changed from the high conduction state to the low conduction state. Characterized variable resistance device. In the variable resistance device according to claim 4,
A memory device that reads out the high conduction state or the low conduction state as storage data by applying a voltage or current between the first electrode and the second electrode within a range not exceeding the turn-on voltage and the turn-off voltage. A variable resistance device characterized by the fact that In the variable resistance device according to claim 5,
The first electrode is arranged as a common electrode that gives a common potential to one surface side of the organic film.
By arranging the second electrode as a plurality of electrodes that give individual potentials to the other surface side of the organic film,
A variable resistance device characterized by being a memory integrated device. In the variable resistance device according to claim 4,
By applying a voltage or current between the first electrode and the second electrode within a range not exceeding the turn-on voltage and the turn-off voltage, the high conduction state is used as the switch ON state, and the low conduction state is used. A variable resistance device characterized by being a switching device that uses the switch off state. The variable resistance device according to any one of claims 1 to 3.
The first electrode is used as a material capable of forming a channel path.
A gate mechanism for controlling the channel path of the first electrode is provided.
The channel path is controlled in the open direction via the gate mechanism, and a turn-on voltage is applied to the channel path of the first electrode, the stacking direction of the organic film, and the second electrode to form a transistor. A variable resistance device characterized by that. In the method for manufacturing a variable resistance device according to any one of claims 1 to 8.
A forming step for forming the first electrode, the organic film, and the second electrode is provided.
A method for manufacturing a variable resistance device, which comprises controlling the anisotropic orientation by the formation temperature of the organic film in the process of forming the organic film. In the method for manufacturing a variable resistance device according to claim 9.
In the process of forming the organic film, by setting the film thickness of the organic film,
A method for manufacturing a variable resistance device, which comprises controlling a turn-on voltage at which the variable resistance device turns on and a turn-off voltage at which the variable resistance device turns off.

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