JPH01300227A - Display element - Google Patents

Abstract

PURPOSE:To prevent display information from being lost owing to an unexpected power failure without requiring any external electric power by arranging an MIM and a heat generating resistance body electrically in series and providing memory performance for the switching characteristics of the MIM. CONSTITUTION:A couple of electrodes 15 and 17 are arranged on a substrate 11 and there is an organic insulating layer(MIM) 16 which has periodic layer structure of an organic insulator between the electrodes 15 and 17; and the heat generating resistance body 14 is arranged in contact with one end of an upper electrode 15, an optical modulation body 13 is provided on this heat generating resistance body 14, and an optical modulation body protection plate 12 is provided on the optical modulation body 13. Further, the MIM 16 and heat generating resistance body 14 are arranged electrically in series, and the MIM 16 has the memory performance for the switching characteristics. Consequently, memory requires no electric power, so no external electric power is required to store the display information and the states of the display information and switching characteristics of the MIM 16 are invariably united, so the display information is not lost owing to the unexpected power failure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a display element characterized by having an organic insulating layer and having a memory property using a memory property in switching characteristics.

[Conventional technology] In recent years, advances in office automation (OA) include
There are many amazing things, and the development of office equipment with advanced functions is desired. A typical office device is a word processor (WP), but the current WP requires a display element and a portion of memory independently, resulting in a complicated structure, which poses a problem when attempting to miniaturize. Also the current WP
When using an AC power source, there was a serious problem in that created documents would be lost in the event of a power outage. For this reason, there has been a demand for display elements that can store display information within themselves without applying external power. Some of these display elements use ferroelectric liquid crystals, but liquid crystal display elements have the disadvantage of a narrow viewing angle.

[Problems to be Solved by the Invention] That is, the present invention provides a display element in which the display element itself has a memory property by utilizing the memory property of switching characteristics in MIM.

FIG. 1 is a schematic diagram of a display element of the present invention.

The display element shown in FIG. 1 has a pair of electrodes on -L of the substrate 11 and an organic insulating layer 16 having a periodic layer structure of an organic insulator between the electrodes 15 and 17. A heating resistor 14 is disposed so as to be in contact with one end of the heating resistor 14.
A light modulator protection plate 12 is provided on top of the light modulator 3.

The light modulator protection plate constituting the display element of the present invention includes:
Any conventionally known transparent materials such as glasses, plastics, dielectrics, etc. can be used, and these transparent protective plates have a thickness of about 10
It is preferred to use materials with a thickness of 0μ- to 2+a+w.

The light modulator in the present invention is made of a polymer solution or a liquid containing a surfactant, and exhibits light scattering properties when heated, and exhibits translucency when cooled.

The poly used here includes polypropylene,
Polyalkenes such as polyisobuty7, polybutadiene,
Polydienes such as polyisoprene, polyvinyls such as polyvinyl acetate, poly(meth)acrylate, poly(meth)acrylamide, polyethers such as polyethylene oxy-F, polyimines such as polyethyleneimine, polyoxyethylene azide, etc. Polyesters such as voile,
Polyamides such as polyglycine, copolymers made of these and other copolymerizable monomers, other conventionally known chain polymers, or polymers with a three-dimensional network structure in which the polymer chains are moderately crosslinked. can be mentioned.

On the other hand, as a solvent for the polymer, water, various organic solvents, or mixtures thereof can be used, such as water; alcohols such as methanol and ethanol; ketones such as acetone and methyl ethyl ketone; pentane, cyclohexane,
Hydrocarbons in the benzene list; halogenated hydrocarbons such as tetrachloroethane and dichlorobenzene; ethyl formate, ethyl acetate, and isoamyl acetate; ethers such as dioxane and cyclisime; amides such as dimethylformamide and dimethylacetamide Sulfur-containing solvents such as dimethyl sulfoxide; or mixed solvents thereof; and solutions in which various solutes such as lithium perchlorate, ammonium propionate, urea, and cricose are dissolved in these solvents.

The polymer solution used as a light modulator in the present invention is formed from the above-mentioned polymer and solvent, but a particularly important point is the combination of the polymer and the solvent, and the temperature is preferably not too high. It is preferable to select and use a material so that it becomes cloudy due to heat absorption in a temperature range of about 10 to 100° C. and exhibits light scattering properties.

In addition, examples of the cloud point-containing surfactant, which is another material constituting the light modulator of the present invention, include polyoxyethylene-based nonionic surfactants, esters such as polyoxyethylene laurate, and polyoxyethylene-based nonionic surfactants. Ethers such as oxyethylene octylphenol ether, amines such as polyoxyethylene stearylamine, and amides such as polyoxyethylene laurylamide are suitable.

On the other hand, solvents constituting this surfactant include water, or water and alcohols such as methanol, ethanol, and ethylene glycol, ethers such as tetrahydrofuran and dioxane, ketones such as acetone and methyl ethyl ketone, and pyridine and triethylamine. Mixed solvents with organic solvents such as amines and amides such as dimethylformamide, or solutions in which salts such as potassium chloride, lithium perchlorate, organic solutes such as urine J, etc. are added to these solvents are suitable. .

The suitable thickness of the polymer solution used as the light modulator of the present invention or the liquid layer containing the surfactant having a cloud point is 1 IL+a -1000 ILs,
Preferably, lμra - 100μJ is the optimal range.

The material of the heating resistor 14 used in the present invention includes metal compounds such as hafnium boride and tantalum nitride, alloys such as nichrome, or ITO (Indium TinOxi).
A transparent oxide such as de) is used, and the film thickness is 50
A range of 0-5000A is optimal. Further, an insulating layer (protective film) is formed on the surface of the heating resistor 14 and between it and the light modulator 13.

Regarding the formation of the organic insulating layer, it is possible to specifically apply the vapor deposition method and the cluster ion beam method, but among the known conventional techniques, LB is preferred due to its controllability, ease, and reproducibility
The method is highly preferred.

According to this LB method, it is possible to easily form a monomolecular film of an organic compound having a hydrophobic site and a lignophilic site in one molecule or a cumulative film thereof on a substrate, and the thickness is on the order of a molecule. Moreover, it is possible to stably supply a uniform and homogeneous ultra-thin organic film over a large area.

The LB method is based on the LB method, in which a molecule has a structure that has a lymophilic site and a hydrophobic site within one molecule, and when the balance between the two (balance of amphiphilicity) is maintained appropriately, the molecule has a lignophilic site on the water surface. This is a method of creating a monomolecular film or a cumulative film thereof by utilizing the fact that the monomolecular layer is formed with the group facing downward.

Examples of the group constituting the hydrophobic moiety include various hydrophobic groups such as generally widely known saturated and unsaturated hydrocarbon groups, fused polycyclic aromatic groups, and chain polycyclic phenyl groups. Each of these constitutes a hydrophobic portion singly or in combination. On the other hand, the most typical constituent elements of the wood-philic moiety are, for example, carboxyl groups, ester groups, acid amide groups, imide groups, hydroxyl groups, sulfonyl groups, phosphoric acid groups, and amino groups (1, 2, 3, and 4 Examples include parent tree groups such as class).

If the molecule has a balance of these hydrophobic groups and hydrophilic groups, migration is the formation of a monomolecular film on the water surface. Generally, these molecules form an insulating monomolecular film, and the monomolecular cumulative film also exhibits insulating properties, so it can be said to be an extremely suitable material for the present invention. - By way of example, the following molecules may be mentioned:

Molecules with a (+)π electron level; Dyes with a porphyrin skeleton such as phthalocyanine and tetraphenylporphyrin, azulene dyes with a squarylium group and croconic methine group as bonding chains, and 2 such as quinoline, benzothiazole, benzoxazole, etc. Cyanine-based similar dyes bonded by nitrogen-containing heterocycles, squarylium groups, and croconic methine groups, or chain compounds in which cyanine dyes, condensed polycyclic aromatics such as anthracene, pyrene, and aromatic rings to heterocyclic compounds are condensed. Such.

(2) High molecular compounds polyimide derivatives, polyamic acid derivatives, polyamide derivatives, various fumaric acid copolymers, various maleic acid copolymers, polyacrylic acid derivatives, various acrylic acid copolymers,
Polydiacetylene derivatives, various vinyl compounds, synthetic polypeptides, biopolymer compounds such as bacteriorhodopsin and cytochrome C, etc.

(3) Fatty acids Carboxylic acids and carboxylic acid salts having long-chain alkyl groups, or fluorine-substituted products thereof, esters having at least one long-chain alkyl group, sulfonic acids and salts thereof, phosphoric acids and salts thereof or fluorine-substituted products of these.

Among these compounds, from the viewpoint of heat resistance, it is desirable to use polymeric compounds or Ota-like compounds such as phthalocyanine, and in particular polyimides, polyacrylic acids, various fumaric acid copolymers, or various If a polymeric material such as a maleic acid copolymer is used, not only the heat resistance is excellent, but also the film thickness per layer can be about 5A.

In the present invention, it goes without saying that materials other than those mentioned above are also suitable as long as they are suitable for the LB method.

Such amphiphilic molecules form a monomolecular layer on the water surface with the parent group facing downward. At this time, the monomolecular layer on the water surface has the characteristics of a two-dimensional system, and when the molecules are sparsely dispersed, the two-dimensional ideal gas equation, πA, is expressed between the area per molecule A and the surface pressure π. =kT holds true, resulting in a ``gas film''. Here, k is Portzmann's constant and T is absolute temperature. If A is made sufficiently small, the intermolecular interaction becomes strong, resulting in a two-dimensional solid condensation film (or solid film).A condensation film can be formed on the surface of any object with various materials and shapes, such as glass or resin. This method can be used to form a monomolecular film or a cumulative film thereof, which can be used as an organic insulating layer in the MIM portion of the present invention.

As a specific manufacturing method, for example, the method shown below can be mentioned.

Chloroform and benzene for the desired organic compound.

The solution is dissolved in a solvent such as acetonitrile, and then the solution is spread on the aqueous phase 21 using a suitable apparatus as shown in FIG. 2 of the attached drawings to form a spread layer 22 of the organic compound in the form of a film.

Next, a partition plate (or float) 23 is provided to prevent this spread layer 22 from spreading freely on the aqueous phase 21 and spreading too much, and by restricting the surface edges of the spread layer 22, the state of aggregation of the film substance is controlled. ,
Obtain the surface pressure π proportional to the collective state. This partition plate 2
3, the area of the spreading layer 22 can be reduced to control the aggregation state of the film material, and the surface pressure can be gradually increased to set the surface pressure π suitable for film production. By gently raising or lowering the clean substrate 24 vertically while maintaining this surface pressure, a monomolecular film of an organic compound is formed on the substrate 24.
transferred to the top. Such a monomolecular film is shown in Figure 3(a).
Alternatively, it is a film in which molecules are arranged in an orderly manner, as schematically shown in FIG. 3(b).

The monomolecular film 31 is manufactured as described above, and by repeating the above operations, a desired number of cumulative films can be formed. To transfer the monolayer onto the substrate, in addition to the vertical dipping method described above,
Methods such as the horizontal adhesion method and the one-turn cylinder method are also possible.

In the above-mentioned vertical immersion method, when a substrate with a wood-loving surface is lifted out of water in a direction across the water surface, a monomolecular film 31 of an organic compound with the wood-loving parts 32 of the organic compound facing the substrate 24 is formed on the substrate 24. When the substrate 24 is moved up and down as described above (FIG. 3(b)), the monomolecular films 31 are stacked one by one in each step, forming a cumulative film 41. Since the direction of the film-forming molecules is reversed between the pulling process and the dipping process, this method forms a Y-shaped film in which the hydrophobic parts 33a and 33b of the organic compound face each other between each layer of the monomolecular film (the fourth Figure (a)). On the other hand, in the horizontal deposition method, a monomolecular film 31 is formed on the substrate 24 in which the hydrophobic sites 33 of the organic compound are oriented toward the substrate 24 (FIG. 3(a)). Even if the films 31 are accumulated, there is no change in the orientation of the film-forming molecules, and an X-shaped film is formed in which the hydrophobic parts 33a and 33b face the substrate 24 in all layers (the fourth
Figure (b)). On the contrary, in all layers, the woody part 32a
, 32b facing the substrate 24 side is called a Z-type film (FIG. 4(c)).

The method of transferring the single molecules 1931 onto the substrate 24 is not limited to the above method, and when a large-area substrate is used, a method of extruding the substrate from a roll into an aqueous phase may also be adopted. Further, the directions of the hydrophilic groups and hydrophobic groups described above toward the substrate are in principle, and can be changed by surface treatment of the substrate, etc.

As described above, the monomolecular film 31 of the organic compound or its ggat is formed on the substrate 24.

The substrate 24 for supporting the thin film on which organic materials are laminated as described above may be made of any material such as metal, glass, ceramics, or plastic materials, and biomaterials with extremely low heat resistance may also be used.

The substrate 24 as described above may have any shape and is preferably flat, but is not limited to a flat plate.

That is, the above film forming method has the advantage that a film can be formed in accordance with the shape of the surface of the substrate, no matter what shape it is.

As described above, the organic insulating layer of the MIM in the present invention is made by periodically stacking molecules having a group with a relatively large π (pi) level and a group with a σ (sigma) electronic level. It is an organic insulator with a periodic potential structure, and by passing a current in a direction parallel to the periodic direction, it has achieved a switching memory function not found in conventional MIM elements.

The switching memory characteristics are fi fullll in the current characteristics (Vl characteristics) when a voltage is applied between the upper and lower electrodes of the MIM part (Fig. 5), and the stable ON state as shown in Fig. 6 ( It is possible to create a resistance value of several tens of Ω) and an OFF state (resistance value of more than MΩ), and the ON→OFF state
Switching to F shows a certain threshold voltage (about 1 to 2 V/20 layers) L, switching from OFF to ON occurs at about -2 to -5 V, and the switching speed is 0N10FF below i p, sec. Ratio (ON state and OF
The ratio of resistance values in the F state) was 5 digits or more.

The present invention realizes a display element with memory properties by using the switching memory characteristics of MIM including such an organic insulating layer.

On the other hand, the electrode material for sandwiching the LBH'U may be any material as long as it has high conductivity, such as Au, P
t, Ag, Pd, A+? , In, Sn, P
There are many materials including metals such as B, alloys thereof, graphite, silicide, and even conductive oxides such as ITO, and these materials can be considered to be applied to the present invention. As a method for forming electrodes using such materials, conventionally known thin film techniques are sufficient.

However, care must be taken here to avoid damaging the LB layer when forming electrodes on the LB film in the production of the MIM of the present invention.
Avoid processing steps in manufacturing processes that require temperatures (°C). Further, as for the electrode material directly formed on the substrate, it is preferable to use a conductive material such as a noble metal or an oxide conductor such as ITO that does not form an insulating oxide film on the electrode surface when forming the LE film.

[Function] Next, the principle of operation of this display element will be explained using FIG. 1. It is assumed that Ml and M are initially in the OFF state.

(1) Set the operation switch 19 for making the light modulator opaque to M, and apply voltage to the MIM from the power source 18 to turn the MIX ON. Next, turn switch 19 to H.
A voltage is applied to the heat generating resistor 14 and the MIM to cause the heat generating resistor layer to generate heat, thereby heating the light modulator 13 and making the light modulator opaque. At this time, the applied voltage and the resistance value of the heating resistor are set so that the light modulator can be appropriately heated and the MIX can be kept ON.

(2) Operation to make the light modulator transparent From the state of (1) above, set the switch 19 to M and
Apply voltage to MIM from 8 and turn IN to OFF state.

Here, even if the switch 19 is set to H and the same voltage applied in series to the MIM heating resistor 14 is applied in the operation of making the light modulator 13 opaque, the IM is in the OFF state where the resistance is high. Almost no current flows through the heating resistor 14, and the heating resistor 4 does not generate heat, so the light modulator 1
3 becomes a transparent state.

(3) Reading the memory Even if you set the switch to neutral or turn off the power supply 18 from either state (1) or (2) above, the OFF and ON states in the MIM are stored in memory, so you cannot switch it again. If you return it to H or turn on the power, the original state will be restored.

As described above, the present invention focuses on the memory-like switching characteristics of HIH containing organic materials, and
The invention was completed based on the knowledge that if incorporated into a display element as a memory, a display element could be obtained that solved the various drawbacks of the prior art.

[Examples] Hereinafter, the present invention will be described in more detail according to more specific examples.

Example 1 The device shown in FIG. 1 was manufactured by the procedure shown below.

Cr was deposited to a thickness of 500A as an undercoat layer on a glass substrate (0059 manufactured by Corning) by vacuum evaporation method, and Au was further deposited by the same method (film thickness 1000A) L, width l
A striped base electrode was formed. The electrode substrate made in this way is hexamethyldisilane (HMDS).
After hydrophobic treatment by leaving it in saturated steam for a day and night, L
A 10-layer cumulative film (4OA in film thickness) of a polyimide monomolecular film was formed using method B, and an insulating thin film 16 was formed.

The details of the method for producing the polyimide monomolecular cumulative film are described below.

After dissolving the polyamic acid shown in formula (1) in a mixed solvent of N,N'-dimethylacetamide-benzene (1:IV/'V) (concentration in terms of monomer IXIO-3M), separately prepared N,N - 1:2 (V/V) of a 10-3M solution of dimethyloctadecylamine
4. : By mixing, a polyamic acid octadecylamine salt solution shown in formula (2) was prepared.

'11HN(CH3)2 (CH2)+ 7 CH3 The solution was added to the aqueous phase 21 (second phase) consisting of pure water at a water temperature of 20°C.
(Figure), and a monomolecular film was formed on the water surface. After evaporating and removing the solvent, a float was moved as a partition plate 23 to reduce the developed area and the surface pressure was increased to 25 mN/a. While keeping the surface pressure constant, the substrate with the lower electrode was gently immersed in a direction across the water surface at a speed of 5 am/l1in, and then gently pulled up at a rate of 5 am/win to form two layers of Y.
A type monomolecular cumulative film was created. Repeat this operation 10 times
The zero-order substrate on which a monomolecular cumulative film of polyimide acid octadecylamine salt was formed was immersed in a mixed solution of acetic anhydride, pyridine, and benzene (1:1:3) for 12 hours, and the polyimide acid octadecylamine salt was added to the imide layer. 3)
, @HN(CH3)2 (CH2)170H3 A single-layer polyimide monomolecular cumulative film was obtained.

Next, on the surface of the polyimide monomolecular cumulative film, an upper electrode 15 was formed by vacuum evaporation (film thickness 1000 Å) of AI) in a stripe shape with a width of 1 snow layer so as to be perpendicular to the lower electrode 17.

Next, as shown in FIG. 1, a tantalum nitride film having a thickness of 100 OA was deposited on a stripe having a width of 0.9I1m by sputtering so as to cover one end of the AR main electrode, thereby forming a heating resistor 14. Furthermore, an insulating layer with a thickness of 2p,
TS 5102M was laminated by sputtering method (
However, in order to attach a lead wire later, the end of the heat generating resistor layer not in contact with Ai) was shielded so as not to be covered with the Si02 film. This heating resistor layer and a transparent protection plate were bonded to each other with a Mylar film as a spacer, facing each other with a gap of 10 layers.

The light modulator was created as follows. First, the following solutions A and B were prepared in advance.

A light modulator was produced by mixing liquids A and B in a nitrogen atmosphere and filling and sealing the mixture into the gap between the heat generating resistor and the transparent protective plate to form a gel layer.

When the above-described operation 1 was carried out on the thus obtained light modulation element with memory properties, memory properties in display were confirmed with good reproducibility, and it was found that the light modulation element had sufficient practicality.

Example 2 In the device configuration described in Example 1, the lower electrode was formed of BiO, lutetium diphthalocyanine [LuH(Pc) 2] was formed as the LB layer by the following method, and the substrate was subjected to hydrophobic treatment. A display element having the same element configuration as in Example 1 was manufactured except that .

To form the LB layer, first, LuH(Pc)z is added at a concentration of 0.5+.
Solution dissolved in wg/mJll (solvent: chloroform/
The substrate was previously immersed in a mixture of trimethylbenzene/acetone (1/l/2 i) at a water temperature of 20° C., and then spread on pure water to form a monomolecular film on the water surface. After waiting for the solvent to evaporate and be removed, the surface pressure of the monomolecular film was increased to 20+sN/cm, and while keeping this pressure constant, the previously immersed substrate was moved at a speed of 3 mt in the direction across the water surface.
It was gently pulled up after 1 minute, and one monolayer of monolayer was accumulated on the electrode substrate. Subsequently, 11 layers were deposited on the ITO by repeatedly dipping and pulling the material gently across the water surface at the same vertical speed of 3/min.

A cumulative film of 21 and 31 layers was formed.

The display element produced as described above was prepared in the same manner as in Example 1.
When the operation described in [Effect] was performed, the memorability of the display was confirmed with good reproducibility.

Example 3 In the element configuration described in Example 1, the lower electrode was A11 (
A display element was fabricated with the same element configuration as in Example 1, except that a monomolecular film of squarylum bis-6-octyl azulene (SOAZ) was formed as LBi in the following manner. .

To form the LB layer, first 5OAZ was added at a concentration of 0.2 mg/mj.
) to pH 8 with KHC (h).
, 7 CdC1)2 concentration 5 × 10−'mo
j)/j' was developed on an aqueous phase at a water temperature of 20°C to form a monomolecular film on the water surface. After waiting for the solvent to evaporate, the surface pressure of the monomolecular film was increased to 20 mN/m, and while keeping this pressure constant, the substrate was moved at a speed of 10 mN/m in the direction across the water surface.
After gentle immersion at m+s/min, the film was then gently pulled up at 5111 Z min to accumulate two layers of Y-type monomolecular film.

By repeating this operation an appropriate number of times, 2°4, 8, 12.20.30.40. EiO
On the film surface of the 0th-order film on which 8 types of cumulative films of layers were formed, a stripe shape Aj) with a width of 1 layer is perpendicular to the base electrode.
An electrode (thickness: 150 OA) was vacuum deposited while keeping the substrate temperature below room temperature to form the upper electrode.

The display element produced as described above was prepared in the same manner as in Example 1.
When the operation described in [Effect] was performed, the memorability of the display was confirmed with good reproducibility.

Examples 4 to 11 Samples having the same element structure as Example 1 were prepared using the electrode materials and insulating materials shown in Table 1, and their calendar numbers. The metal electrode was formed by vacuum deposition using a resistance heating method.

All of these samples were confirmed to have memory properties in display as in Example 1.

(Left below) R= OC:H(COOH)C2oH4+(CH2)2COOH In the examples described above, the LB method was used to form the insulating layer, but it is difficult to form an extremely thin and uniform insulating organic thin film. Any film forming method that can be used is not limited to the LH method. Specifically, vacuum evaporation methods, electrolytic polymerization methods, CVD methods, etc. can be mentioned, and the range of usable organic materials is expanded.

Regarding the formation of the electrode, as already mentioned, any film forming method that can form a uniform thin film on the organic thin film layer can be used, and is not limited to vacuum evaporation or sputtering.

Further, the material used for the light modulator can be any material that becomes reversibly transparent or opaque depending on the temperature, and is not limited to polymer solutions and surfactants.

Furthermore, the present invention does not limit the substrate material or its shape in any way.

[Effects of the Invention] As explained above, the display element according to the present invention has MIM
Since the memory of the switching characteristics of the MIM does not require power, no external power is required to save the display information, and since the display information and the state of the switching characteristics of the MIM are always integrated, it will not be affected by an unexpected power outage. No display information is lost.

Furthermore, since the light modulator used in the present invention has excellent scattering properties, it is possible to obtain clear and high-resolution images with high contrast, and there is no restriction on viewing angle.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a specific example of a display element of the present invention. FIG. 2 is an explanatory view schematically showing a method of forming an organic dye insulating layer according to the present invention by the LH method. Figures 3a and 3b are schematic diagrams of monomolecular films, and Figures 4a and 4
Figure b and Figure 4C are schematic diagrams of the cumulative film. Fig. 5 is a characteristic diagram showing the electrical characteristics (Vl characteristics) obtained in the device, and Fig. 6 is a diagram showing the electrical characteristics in the ON state and OFF state confirmed in the device. It is. 11... Substrate 12... Light modulator protection plate 13... Light modulator 14... Heat generating resistor 15
...Top electrode 16...Organic insulating layer 17...
・Lower electrode 18...Electrode 19...Switch 21...Aqueous phase 22...Development layer 2
3... Partition plate 24... Board 31...
Monomolecular film 32, 32a, 32b--woodophilic site 33
, 33a, 33b... Hydrophobic site 41... Monomolecular cumulative film

Claims (3)

[Claims] (1) Consisting of a part (MIM) consisting of a pair of electrodes and an organic insulating layer sandwiched between the electrodes, a heating resistor and a light modulator arranged on the heating resistor,
A display element having a configuration in which one end of an upper electrode of a pair of electrodes is in contact with one end of a heating resistor, and the MIM and the heating resistor are arranged so as to be electrically in series, and the MIM has switching characteristics. A display element characterized by having a memory property. (2) The organic insulating layer has a group having only π electron level and σ
2. The display element according to claim 1, further comprising a group having only electronic levels. (3) The display element according to claim 1, wherein the light modulator is a polymer solution or a surfactant solution.