Pressure-sensitive display device

Abstract

Pressure-sensitive display device, including: a sampling substrate (100); a reaction substrate (200) provided on the detection substrate; and Spacers (300) provided between the detection substrate and the reaction substrate to keep the detection substrate apart from the reaction substrate, the recording substrate includes: a flexible substrate (120); and a touch electrode (140) provided on a surface of the flexible substrate facing the reaction substrate, and the reaction substrate comprises: a transparent substrate (220); a transparent electrode (240) provided on a surface of the transparent substrate facing the detection substrate; and a light-emitting layer (262) arranged on the transparent electrode; and wherein each of the spacers has a column shape extending from an upper surface of the reaction substrate to a lower surface of the detection substrate, and wherein the spacers are arranged in rows and columns on the upper surface of the reaction substrate with respect to a plane.

Description

STATE OF THE ART

[0001] The present disclosure relates to a pressure-sensitive display device, and more particularly to a pressure-sensitive display device that detects pressure to generate light at a corresponding position.

[0002] Various pressure sensors have been developed to be applied to electronic skins and robotics using wearable element technology or various electronic element technologies. Matrix-type pressure sensors have been developed in such a way that the pressure sensors are integrated to measure a single pressure or multiple pressures applied within a predetermined range. Applied pressure can be measured using resistance variation type, capacitance variation type, and other pressure-sensitive elements (TFT) in such a way that scanning is performed in a pixel or line unit, a signal of applied pressure is analyzed by scanning, and then position, magnitude, and movement information of the pressure is displayed on a separate display for a user.Currently, an expensive pixelated pressure sensor is manufactured, which scans and analyzes an input signal using the pressure sensor, and then displays the results so that the user can recognize a pressure signal. This makes it difficult to realize an element that simultaneously fulfills functions such as high performance, miniaturization, and intuitive recognition. KR 101077385 B1 describes a resistive touch panel that provides light-emitting feedback. The resistive touch panel is a P-type electrode layer on a surface of the first transparent substrate, and the N-type electrode layer, the N-type semiconductor layer, and the active layer are formed on a surface of the first transparent electrode and the second transparent substrate by stacking them in order with the P-type semiconductor layer. SUMMARY

[0003] The present disclosure provides a pressure sensitive display device with a simple structure and a manufacturing method.

[0004] The present disclosure also provides a pressure sensitive display device having improved electrical characteristics and a method of manufacturing the same.

[0005] The present disclosure also provides a pressure-sensitive display device having high sensitivity and a manufacturing method thereof.

[0006] The subject matter of the present invention is not limited to the foregoing, but other subject matters not described herein will be clearly understood by those skilled in the art from the following descriptions.

[0007] An embodiment of the inventive concept provides a pressure-sensitive display device comprising: a sensing substrate; a reaction substrate provided on the sensing substrate; and spacers provided between the sensing substrate and the reaction substrate to space the sensing substrate from the reaction substrate. Here, the sensing substrate includes: a flexible substrate; and a touch electrode provided on an upper surface of the flexible substrate facing the reaction substrate, and wherein the reaction substrate includes: a transparent substrate; a transparent electrode provided on an upper surface of the transparent substrate facing the sensing substrate; and a light-emitting layer disposed on the transparent electrode.

[0008] In one embodiment, the sensing substrate may be deformed by external pressure so that the touch electrode contacts the light-emitting layer, wherein the light-emitting layer may emit light through contact with the touch electrode.

[0009] In one embodiment, a contact area between the touch electrode and the light-emitting layer may be substantially the same as a light-emitting area of ​​the light-emitting layer.

[0010] In one embodiment, the touch electrode may be flexible.

[0011] In one embodiment, the pressure-sensitive display device may further include an intermediate electrode provided between the flexible substrate and the touch electrode.

[0012] In one embodiment, the intermediate electrode may have a greater resistance than the touch electrode.

[0013] In one embodiment, the touch electrode may have an electrical conductivity that gradually decreases in a direction away from the flexible substrate.

[0014] In one embodiment, each of the spacers may have a line shape extending in a direction parallel to a top surface of the reaction substrate, and the spacers may be arranged in a strip shape or an open ring shape provided on an outer portion of the reaction substrate on a plane.

[0015] In one embodiment, each of the spacers may have a columnar shape extending from an upper surface of the reaction substrate to a lower surface of the sensor substrate, and wherein the spacers may be arranged in rows and columns on the upper surface of the reaction substrate with respect to a plane.

[0016] In one embodiment, the sensing substrate may have a thickness of about 1 µm to about 20 µm.

[0017] In one embodiment, the touch electrode may include a nanowire, a nanofiber, a nanoparticle, a graphene, or a nanotube.

[0018] In one embodiment, the touch electrode may contain a complex in which a nanostructure of a conductive material and a nanostructure of a non-conductive material are mixed.

[0019] In one embodiment, the light-emitting layer may contain a quantum dot material or a perovskite material.

[0020] In one embodiment, the pressure-sensitive display device may further include an electron injection layer provided on a first surface of the light-emitting layer facing the touch electrode or a hole injection layer provided on a second surface of the light-emitting layer facing the transparent electrode.

[0021] In one embodiment, the pressure-sensitive display device may further include a photodiode or a transistor provided under the sensing substrate.

[0022] In one embodiment, the spacer may include a non-conductive adhesive material, and the touch electrode may be fixed by the spacer while being spaced from the light-emitting layer.

[0023] In one embodiment of the inventive concept, a pressure-sensitive display device includes: a transparent first substrate; a first electrode disposed on the first substrate; a light-emitting layer disposed on the first electrode; and a second electrode disposed on the light-emitting layer while being spaced apart from the light-emitting layer. Here, the second electrode includes a flexible conductive material, and the second electrode is deformed by external pressure to contact the light-emitting layer, and a portion of the light-emitting layer that contacts the touch electrode emits light.

[0024] In one embodiment, the pressure-sensitive display device may further include spacers defining a distance between the light-emitting layer and the second electrode.

[0025] In one embodiment, each of the spacers may have a line shape extending in a direction parallel to a top surface of the first substrate, and the spacers may be arranged in a strip shape or an open ring shape provided on an outer portion of the first substrate in a plane.

[0026] In one embodiment, each of the spacers may have a column shape extending from an upper surface of the first substrate to a lower surface of the second substrate, and wherein the spacers may be arranged in row and column on the upper surface of the first substrate with respect to a plane.

[0027] In one embodiment, the pressure-sensitive display device may further include a third electrode provided on the second substrate, and wherein the third electrode may have a greater resistance than the second electrode.

[0028] In one embodiment, the second electrode may have an electrical conductivity that gradually decreases in a direction toward the light-emitting layer.

[0029] In one embodiment, the pressure-sensitive display device may further include a second substrate disposed on the second electrode. Here, the second substrate may include a flexible substrate, and the second substrate may be deformed in conjunction with the second electrode when the external pressure is applied.

[0030] In one embodiment, the pressure-sensitive display device may further include an electron injection layer provided on a first surface of the light-emitting layer facing the second electrode, or a hole injection layer provided on a second surface of the light-emitting layer facing the first electrode. SHORT DESCRIPTION OF THE CHARACTERS

[0031] The accompanying drawings serve to further understand the inventive concept and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the inventive concept and, together with the description, serve to explain principles of the inventive concept. In the drawings: Fig. 1 to 2 are cross-sectional views for explaining a pressure-sensitive display device according to embodiments of the inventive concept; Fig. 3 is an enlarged view for explaining a configuration of a reaction substrate; Fig. 4 to 8 are plan views for explaining the shape of a spacer; Fig. 9 is a band diagram of the pressure-sensitive display device according to the embodiments of the inventive concept; Fig. 10 is a cross-sectional view for explaining an operation of the pressure-sensitive display device according to the embodiments of the inventive concept; Fig. 11 is a band diagram for explaining the operation of the pressure sensitive display device according to the embodiments of the inventive concept; Fig. 12 to 14 are cross-sectional views for explaining an operating range of the pressure-sensitive display device according to the embodiments of the inventive concept; Fig. 15 to 16 are cross-sectional views for explaining the pressure-sensitive display device according to the embodiments of the inventive concept; and Fig. 17 to 20 are cross-sectional views for explaining a method of manufacturing the pressure-sensitive display device according to the embodiments of the inventive concept. DETAILED DESCRIPTION

[0032] Exemplary embodiments of the present invention will be described with reference to the accompanying drawings in order to sufficiently understand constitutions and effects of the present invention. However, the present invention may be embodied in various embodiments and should not be construed as being limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. Furthermore, the present invention is defined only by the scope of the claims. One of ordinary skill in the art to which the present invention relates will understand that the present invention may be practiced in any suitable environment.

[0033] In the following description, technical terms are used only to explain a particular exemplary embodiment without limiting the present disclosure. Terms in a singular form may also include plural forms unless otherwise indicated. The meaning of "comprises" and / or "comprising" refers to a component, step, operation, and / or element and does not exclude other components, steps, operations, and / or elements.

[0034] Throughout the specification, it is understood that when a layer (or coating) is referred to as being "on" another layer or substrate, it may be directly on top of the other layer or substrate, or there may be intervening layers.

[0035] Although terms such as first, second, and third are used to describe various regions and layers (or fine layers) in various embodiments of the present invention, the regions and layers are not limited to these terms. These terms are used only to distinguish one region or layer (or fine layer) from another region or layer (or fine layer). Therefore, a layer referred to as a first layer in one embodiment may be referred to as a second layer in another embodiment. An embodiment described and exemplified herein includes a complementary embodiment. Like reference numerals refer to like elements throughout.

[0036] Unless otherwise defined, the terms used in embodiments of the present invention may be interpreted as having meanings commonly known to a person skilled in the art.

[0037] Hereinafter, a pressure-sensitive display device according to an embodiment of the inventive concept will be described with reference to drawings. Fig. 1 and Fig. 2 are cross-sectional views for explaining the pressure-sensitive display device according to an embodiment of the inventive concept. Fig. Figure 3 is an enlarged view for explaining a configuration of a reaction substrate. Fig. 4 to 8 are plan views to explain the shape of a spacer.

[0038] In relation to Fig. 1, the pressure-sensitive display device may include a first substrate 100, a second substrate 200, and a spacer 300.

[0039] The first substrate 100 may be provided. The first substrate 100 may be a sensing substrate of the pressure-sensitive display device. For example, the first substrate 100 may detect externally applied pressure. The first substrate 100 may include a first sub-substrate 120 and a first electrode 140.

[0040] The first sub-substrate 120 may be provided. The first sub-substrate 120 may be a flexible substrate. For example, the first substrate 120 may include polyimide (PI), polyethylene naphthalate (PEN), polycarbonate (PC), poly(ethersulfone) (PES), poly(ethylene terephthalate) (PET), poly(dimethyl sulfate) (PDMS), or Ecoflex. Although not shown, the first sub-substrate 120 may include a protective layer on a top surface. For example, the protective layer may consist of a single layer or a multilayer thin film containing a silicon oxide (SiOx), a silicon nitride (SiNx), an aluminum oxide (AlOx), parylene, or an organic-inorganic hybrid layer.

[0041] The first electrode 140 may be arranged on a lower surface of the first substrate 120. The first electrode 140 may be a pressure-sensitive electrode. For example, the first electrode 140 may have an electrical conductivity that is changed by external pressure. The first electrode 140 may include a nanostructure made of a conductive material. The nanostructure may be made of, for example, a nanowire, a nanofiber, a nanoparticle, graphene, or a nanotube. For example, the conductive material may include a metal such as silver (Ag), a conductive material such as carbon (C), and a conductive polymer such as poly3,4-ethylenedioxythiophene:polystyrenesulfonate (PEDOT:PSS). Alternatively, the first electrode 140 may include a complex in which a nanostructure made of a conductive material and a nanostructure made of a non-conductive material are mixed.For example, the non-conductive material may include zinc oxide (ZnO), titanium oxide (TiO2), or an organic material. Alternatively, the first electrode layer 140 may include a conductive polymer. The conductive polymer may include, for example, pressure-sensitive rubber (PSR). According to other embodiments, the first electrode 140 may have a different electrical conductivity depending on its position. For example, the electrical conductivity of the first electrode 140 may decrease in a direction away from the first sub-substrate 120.

[0042] Although a first electrode 140 is formed on a surface of the first sub-substrate 120 in Fig. 1, the embodiment of the inventive concept is not limited thereto. As in Fig. As shown in Figure 2, a second electrode 160 may be provided between the first sub-substrate 120 and the first electrode 140. The second electrode 160 may have an electrical conductivity greater than that of the first electrode 140. The second electrode 160 may include a metal thin film such as gold (Au), silver (Ag), copper (Cu), or aluminum (Al), or a conductive polymer thin film such as poly-3,4-ethylenedioxythiophene:polystyrenesulfonate (PEDOT:PSS). Alternatively, the second electrode 160 may include a nanostructure made of a conductive material.

[0043] The first substrate 100 can be deformed by external pressure. This means that the first substrate 100 can be flexible. When the first substrate 100 is deformed, the first electrode 140 and the second electrode 160 in the first substrate 100 can be deformed together, and here, the electrical conductivity of the first electrode 140 can be varied. The first substrate 100 can have a thickness of about 1 μm to about 20 μm. If the first substrate 100 has a thickness greater than about 20 μm, a deformed area of ​​the first substrate 100 may increase upon application of external pressure, and the sensitivity of the pressure-sensitive display device may decrease. However, the embodiment of the inventive concept is not limited thereto.For example, the electrical properties of the first substrate 100 can be changed by an external pressure even if the first substrate 100 has a thickness of less than about 1 µm or more than about 20 µm.

[0044] The second substrate 200 may be provided. The second substrate 200 may be a reaction substrate of the pressure-sensitive display device. For example, the second substrate 200 may generate light in response to external pressure at a location corresponding to the external pressure. This will be described in detail later. The second substrate 200 may include a second substrate 220, a third electrode 240, and a light-emitting part 260.

[0045] The second sub-substrate 220 may be provided. The second sub-substrate 220 may be a transparent substrate. The second sub-substrate 220 may include a transparent material. For example, the second sub-substrate 220 may be made of glass, plastic, or elastomer. Although not shown, the second sub-substrate 220 may include a protective layer on a lower surface. For example, the protective layer may be a single layer or a multi-layer thin film containing a silicon oxide (SiOx), a silicon nitride (SiNx), an aluminum oxide (AlOx), parylene, or an organic-inorganic hybrid layer.

[0046] The third electrode 240 may be disposed on a top surface of the second substrate 220. The third electrode 240 may be a transparent electrode. For example, the third electrode 240 may transmit light in a visible light range. The third electrode 240 may include a transparent conductive material. For example, the transparent conductive material may include an indium tin oxide (ITO), an indium zinc oxide (IZO), or an oxide-metal oxide (OMO) thin film. Alternatively, the third electrode 240 may include a nanostructure such as a nanowire, a nanofiber, a non-particle, a graphene, or a nanotube. Alternatively, the third electrode 240 may include a conductive polymer such as poly(3,4-ethylenedioxythiophene:polystyrenesulfonate) (PEDOT:PSS).

[0047] The light-emitting part 260 may be arranged on the third electrode 240. The third electrode 240 may be a positive electrode of the light-emitting part. The light-emitting part 260 may have a hole transport region 265 (see Fig. 3), a light-emitting layer 262 (see Fig. 3) and an electron transport region 268 (see Fig. 3) which are sequentially laminated from the third electrode 240. The following describes a configuration of the light-emitting part 260 with respect to Fig. 3 described in detail.

[0048] In relation to Fig. 3, the light-emitting layer 262 may be provided on the third electrode 240. The light-emitting layer 262 may generate light by recombining electrons or holes provided from the outside. The light-emitting layer 262 may have a single-layer structure made of a single material, a single-layer structure made of a plurality of different materials, or a multi-layer structure with a plurality of layers made of a plurality of different materials.

[0049] Although the light-emitting layer 262 can typically be used for an organic light-emitting diode (OLED), a quantum dot diode, or a perovskite, the embodiment of the inventive concept is not limited thereto. For example, the light-emitting layer 262 can be an organic light-emitting material containing at least one of a polyfluorene derivative, a (poly)paraphenylenevinylene derivative, a polyphenylene derivative, a polyvinylcarbazole derivative, a polythiophene derivative, an anthracene derivative, a butadiene derivative, a tetracene derivative, a distyrylarylene derivative, a benzazole derivative, or carbazole. Further, the light-emitting layer can be an organic light-emitting material containing a dopant.For example, the dopant may contain at least one of the group consisting of xanthene, perylene, coumarin, rhodamine, rubrene, dicyanomethylenepyran, thiopyran, (thia)pyrilium, a periflanthene derivative, an indenoperylene derivative, carbostyryl, Nile red, and quinacridone.

[0050] In particular, when the light-emitting layer 262 emits red light, the light-emitting layer 262 may contain a fluorescent material containing, for example, tris(dibenzoylmethanato)phenanthoroline europium (PBD:Eu(DBM)3(Phen)) or perylene, and the dopant material of the light-emitting layer 262 may be selected, for example, from a metal complex such as bis(1-phenylisoquinoline)acetylacetonate-iridium (PIQIr(acac)), bis(1-phenylquinoline)acetylacetonate-iridium (PQIr(acac)), tris(1-phenylquinoline)iridium (PQIr) and PtOEP (octaethylporphyrin-platinum (PtOEP)) or an organometallic complex.

[0051] When the light-emitting layer 262 emits green light, the light-emitting layer 262 may contain a fluorescent material, e.g., tris(8-hydroxyquinolino)aluminum (Alq3), and the dopant material of the light-emitting layer 262 may be selected, e.g., from a metal complex such as fac-tris(2-phenylpyridine)iridium (Ir(ppy)3) or an organometallic complex.

[0052] When the light-emitting layer 262 emits blue light, the light-emitting layer 262 may be one selected from the group consisting of, for example, spiro-DPVBi (DPVBi), spiro-6P (-6P), distyrylbenzene (DSB), distyrylarylene (DSA), polyfluorene (PFO)-based polymer, a poly(p-phenylenevinylene) (PPV)-based polymer, and a combination thereof, and the doping material of the light-emitting layer 262 may be selected from, for example, a metal complex such as (4,6-F2ppy)2Irpic or an organometallic complex.

[0053] The hole transport region 265 may be provided between the third electrode 240 and the light-emitting layer 262. The hole transport region 265 may be a region through which a hole injected from the third electrode 240 passes to reach the light-emitting layer 262.

[0054] The hole transport region 265 may include a hole injection layer 263, a hole transport layer 264, and / or a single layer with both a hole injection and a hole transport function. The hole transport region 265 may be composed of a hole injection material and / or a hole transport material.

[0055] When the hole transport region 265 contains the hole injection layer 263, the hole transport region 265 may contain a phthalocyanine compound such as copper phthalocyanine, N,N'-diphenyl-N,N'-bis-[4-(phenyl-m-tolyl-amino)-phenyl]-biphenyl-4,4'-diamine (DNTPD), 4,4',4"-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), 4,4',4"-tris(N,N-diphenylamino)triphenylamine (TDATA), 4,4',4"-tris{N,-(2-naphthyl)-N-phenylamino}-triphenylamine (2TNATA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), Polyaniline / camphorsulfonic acid (PANI / CSA) and polyaniline / poly(4-styrenesulfonate) (PANI / PSS). However, the embodiment of the inventive concept is not limited to these.

[0056] When the hole-transporting region 265 includes the hole-transporting layer 264, the hole-transporting region 265 may include a carbazole-based derivative such as N-phenylcarbazole and polyvinylcarbazole, a fluorine-based derivative, a triphenylamine-based derivative such as N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine (TPD) and 4,4',4''-tris(N-carbazolyl)triphenylamine (TCTA), N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB), and 4,4-bis[N,N-bis(4-methylphenyl)benzenamine] (TAPC). However, the embodiment of the inventive concept is not limited thereto.

[0057] The hole transport region 265 may have a thickness of about 100 Å to about 10,000 Å. When the hole transport region 265 includes the entire hole injection layer 263 and the hole transport layer 264, the hole injection layer 263 may have a thickness of about 100 Å to about 10,000 Å, and the hole transport layer 264 may have a thickness of about 50 Å to about 2,000 Å. When both the hole injection layer 263 and the hole transport layer 264 have a thickness within the above-described range, a satisfactory hole transport characteristic can be achieved without significantly increasing the drive voltage.

[0058] The hole-transport region 265 may further contain, in addition to the materials described above, a charge-generating material to improve electrical conductivity. The charge-generating material may be evenly or unevenly distributed in the hole-transport region 265. The charge-generating material may be, for example, a p-type dopant. Although the p-type dopant may be a quinone derivative, a metal oxide, and a cyano group-containing compound, the embodiment of the inventive concept is not limited thereto. For example, a non-limiting example of the p-type dopant may be a quinine derivative such as tetracyanoquinodimethane (TCNQ) and 2,3,5,6-tetrafluorotetracyanoquinodimethane (F4-TCNQ), and a metal oxide such as a tungsten oxide and a molybdenum oxide; the embodiment of the inventive concept is not limited thereto.

[0059] The electron transport region 268 may be arranged on the light-emitting layer 262. The electron transport region 268 may be a region through which an electron injected from the first electrode 140 passes to reach the light-emitting layer 262. Although the first electrode 140 and the light-emitting part 260 are arranged in a structure of Fig. 1 are spaced apart from each other, a contact operation between the first electrode 140 and the light-emitting part 260 will be described in detail later.

[0060] Although the electron-transport region 268 may include at least one of a hole-stopping layer, an electron-transport layer 267, and an electron-injecting layer 266, the embodiment of the inventive concept is not limited thereto. For example, although the electron-transport region 268 may have a structure of the electron-transport layer 267 / the electron-injecting layer 266 or the hole-stopping layer 267 / the electron-transport layer 267 / the electron-injecting layer 266 sequentially laminated from the light-emitting layer 262, or a single-layer structure in which at least two of the above-described layers are combined, the embodiment of the inventive concept is not limited thereto.

[0061] When the electron transport region 268 contains the electron transport layer 267, the electron transport region 268 can contain tris(8-hydroxyquinolinato)aluminum (Alq3), 1,3,5-tri(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl (TPBi), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), 3-(4-biphenylyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (tBu-PBD), Bis(2-methyl-8-quinolinolato-N1,O8)-(1,1'-biphenyl-4-olato)aluminum (BAlq), beryllium bis(benzoquinolin-10-olate) (Bebq2), 9,10-di(naphthalen-2-yl)anthracene (ADN), and a mixture thereof. However, the embodiment of the inventive concept is not limited thereto.

[0062] The electron-transport layer 267 may have a thickness of about 100 Å to about 1000 Å. When the electron-transport layer has a thickness within the above-described range, a satisfactory electron-transport characteristic can be achieved without significantly increasing the drive voltage.

[0063] If the electron-transport region 268 includes the electron-injection layer 266, the electron-transport region 268 may be made of lanthanum metal such as LiF, lithium quinolate (LiQ), Li2O, BaO, NaCl, CsF, and Yb, or metal halides such as RbCl and RbI. The electron-injection layer 266 may be made of a material in which the electron-transport material and an insulating organometallic salt are mixed. The organometallic salt may be a material with an energy band gap of about 4 eV or more. For example, the organometallic salt may include metal acetate, metal benzoate, metal acetoacetate, metal acetylacetonate, or metal stearate.

[0064] The electron injection layer 266 may have a thickness of about 1 Å to about 100 Å. When the electron injection layer 266 has a thickness within the above-described range, a satisfactory electron injection characteristic can be achieved without significantly increasing the drive voltage.

[0065] As described above, the electron transport region 268 may include the hole-stopping layer. Although the hole-stopping layer may include, for example, at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and 4,7-diphenyl-1,10-phenanthroline (Bphen), the embodiment of the inventive concept is not limited thereto. The hole-stopping layer may have a thickness of about 20 Å to about 1000 Å. When the hole-stopping layer has a thickness within the above-described range, a satisfactory hole-stopping property can be achieved without significantly increasing the driving voltage. The above-described light-emitting part 260 may be provided.

[0066] Although a configuration of the light-emitting part 260 including the hole-transport region 265, the light-emitting layer 262, and the electron-transport region 268, which are sequentially laminated on the third electrode 240, the embodiment of the inventive concept is not limited thereto. Alternatively, the light-emitting part 260 of the pressure-sensitive display device according to the embodiments of the inventive concept may include the electron-transport region 268, the light-emitting layer 262, and the hole-transport region 265, which are laminated in a reverse order to that shown in FIG. Fig. 3 are laminated. For example, the light-emitting part 260 may have a configuration in which the electron-transport region 268, the light-emitting layer 262, and the hole-transport region 265 are sequentially laminated on the third electrode 240. In this case, the electron-injection layer 266, the electron-transport layer 267, the light-emitting layer 262, the hole-transport layer 264, and the hole-injection layer 263 may be sequentially laminated on the third electrode 240.

[0067] In relation to Fig. 1 again, the spacer 300 can be provided between the first substrate 100 and the second substrate 200. The spacer 300 can allow the first substrate 100 and the second substrate 200 to be spaced apart from each other. Here, the first substrate 100 and the second substrate 200 can be arranged such that the first electrode 140 of the first substrate 100 and the light-emitting part 260 of the second substrate 200 are opposite each other. In particular, the spacer 300 can allow the first electrode 140 of the first substrate 100 and the light-emitting part 260 of the second substrate 200 to be spaced apart from each other. Here, the light-emitting part 260 can contact the third electrode 240 and be spaced apart from the first electrode 140. The third electrode 240 may be a positive electrode of the light-emitting part 260, and the first electrode 140 may be a negative electrode of the light-emitting part 260.That is, the light-emitting part 260 can only be connected to the positive electrode. The spacer 300 can secure the first substrate 100 to the second substrate 200. For example, the spacer 300 can contain a non-conductive adhesive material.

[0068] The spacer 300 can be provided in several forms. With respect to a plane, the spacers 300 can be provided on outer parts of the first substrate 100. A region RG (see Fig. 4 and Fig. 5) surrounded by the spacers 300 between the first substrate 100 and the second substrate 200 can be defined as a sensor area for detecting an external pressure. The spacers 300 can have a line shape provided at both ends of the second substrate 200. For example, as shown in Fig. 4, the spacers 300 are provided at both ends of the second substrate 200 in a first direction D1 and extend in a second direction D2 perpendicular to the first direction D1. The spacers 300 can also be arranged in strips. For example, as shown in Fig. 5, the spacers 300 on the second substrate 200 may extend in the second direction D2 and be arranged periodically in the first direction D1.

[0069] According to another embodiment, a spacer 300 may be mounted on an outer part ER (see Fig. 6) of the second substrate 200.

[0070] For example, as in Fig. 6, the spacer 300 may be disposed on the outer part ER of the second substrate 200 to surround a space between the first substrate 100 and the second substrate 200.

[0071] That is, the spacer 300 may have an open ring shape along the outer part ER of the second substrate 200. For example, the spacer 300 may include a connecting portion 302 that connects to the space between the first substrate 100 and the second substrate 200 while surrounding the first substrate 100 and the second substrate 200. Thus, when the first substrate 100 is deformed by external pressure, air or gases in the space between the first substrate 100 and the second substrate 200 can be discharged through the connecting portion 302. When the external pressure is removed from the first substrate 100 and the first substrate 100 is returned to its original shape, air or gases can be introduced through the connecting portion 302 between the first substrate 100 and the second substrate 200.Thus, even after external pressure is applied and removed, the space between the first substrate 100 and the second substrate 200 can maintain a constant pressure, and the pressure-sensitive display device cannot be damaged by a pressure difference. With respect to a plane, the inner region RG of the spacer 300 can be defined as a sensor region for detecting the external pressure. Although not shown, the spacer 300 can have a lattice shape that divides the space between the first substrate 100 and the second substrate 200.

[0072] According to another embodiment, the spacer 300, which has the shape of a post, can be provided in several designs. The spacers 300 can each extend from the upper surface of the second substrate 200 to the lower surface of the first substrate 100. The spacers 300 can be provided on the outer part ER of the second substrate 200. For example, as shown in Fig. 7, the spacers 300 may extend on the second substrate 200 in the second direction D2 and be arranged periodically in the first direction D1. Alternatively, the spacers 300 may be arranged in rows and columns on the second substrate 200. For example, as shown in Fig. 8, the spacers can be arranged in the first direction D1 and in the second direction D2.

[0073] The pressure-sensitive display device described above can be provided. Hereinafter, an operation of the pressure-sensitive display device according to the embodiments of the inventive concept will be described with reference to Fig. 1 and 9 to 11.

[0074] Fig. 9 is a band diagram of the pressure sensitive display device according to embodiments of the inventive concept. Fig. 10 is a cross-sectional view for explaining the operation of the pressure sensitive display device according to the embodiments of the inventive concept. Fig. 11 is a band diagram for explaining the operation of the pressure sensitive display device according to the embodiments of the inventive concept.

[0075] Fig. 1 and Fig. 9 show a state in which no external pressure is applied to the pressure-sensitive display device.

[0076] The light-emitting part 260 may include layers with different energy bands. Generally, an organic material has a molecular bonding force that is relatively extremely weaker than an ionic bonding force, etc. Therefore, an electron energy level of an organic layer is quantized and represented as an energy band with a predetermined gap. An energy band of an organic layer may be defined by a gap between a lowest unoccupied molecular orbital (LUMO) energy level and a highest occupied molecular orbital (HOMO) energy level. The LUMO energy level, which is a lowest energy level where an electron is not filled, may correspond to a lower energy level at the bottom of a conduction band of an inorganic semiconductor. The LUMO energy level corresponds to an electron affinity of a corresponding layer.

[0077] As in Fig. 1, when no external pressure is applied to the first substrate 100, the first electrode 140 of the first substrate 100 may be spaced apart from the light-emitting part 260 of the second substrate 200. That is, as shown in Fig. 9, an electrical signal from the first electrode 140 cannot be applied to the light-emitting part 260, and no light can be generated from the light-emitting part 260.

[0078] Fig. 10 and Fig. 11 show a state in which external pressure is applied to the pressure-sensitive display device.

[0079] When a predetermined electric field is applied to the light-emitting layer 262, electrons present at the first electrode 140 (the negative electrode) move to a neighboring layer through the electric field. The electric field increases as the gap between the LUMO energy levels of neighboring layers increases.

[0080] The LUMO energy level is associated with the movement of electrons. The electrons can move from a layer with a low LUMO energy level to a layer with a high LUMO energy level due to the applied electric field. Generally, the electron-transport region 268 has a LUMO energy level between a work function of the first electrode 140 and a LUMO energy level of the light-emitting layer. Likewise, if the electron-transport region 268 comprises a plurality of layers, the LUMO energy level may increase in a direction from the first electrode 140 to the light-emitting layer 262. However, the embodiment of the inventive concept is not limited thereto. The HOMO energy level is a highest energy level at which electrons are filled. The HOMO energy level may correspond to an energy level at the top of a valence band of an inorganic semiconductor.A layer has an energy level corresponding to the ionization potential. The ionization potential is the energy required to ionize a material. As the ionization potential increases, ionization of the material becomes more difficult.

[0081] When a predetermined electric field is applied to the light-emitting layer 262 of the light-emitting part 260, holes present at the third electrode 240 (the positive electrode) move to an adjacent layer due to the electric field. Here, as the gap between the HOMO energy levels of adjacent layers increases, a larger electric field is required.

[0082] The HOMO energy level is associated with the movement of holes. The holes can move from a layer with a high HOMO energy level to a layer with a low HOMO energy level due to the applied electric field. Generally, the hole-transport region 263 and 264 has a HOMO energy level between a work function of the third electrode 240 and a HOMO energy level of the light-emitting layer 262. Even if the hole-transport region 263 and 264 comprises a plurality of layers, the HOMO energy levels can decrease in a direction from the third electrode 240 to the light-emitting layer 262. However, the embodiment of the inventive concept is not limited thereto.

[0083] As in Fig. As shown in Figure 10, the first substrate 100 can be deformed by external pressure to contact the second substrate 200. For example, the first electrode 140 of the deformed first substrate 100 can contact the light-emitting part 260 of the second substrate 200. Here, when a shape of the first electrode 140 of the first substrate 100 is deformed and compressed, an electrical conductivity of the first electrode 140 can vary, and a charge (e.g., an electron) can be generated in the first electrode 140. As shown in Fig. As shown in Figure 11, the charge generated in the first electrode 140 can be transferred to the light-emitting layer 262. Thus, a predetermined electric field can be applied to the light-emitting layer 262 between the first electrode 140 and the third electrode 240.

[0084] An electron generated in the first electrode 140 can pass through the electron transport region 268. The electron can reach the light-emitting layer 262. A hole in the third electrode 240 can pass through the hole transport region 263 and 264. The hole can reach the light-emitting layer 262. The electron and the hole can be coupled at the light-emitting layer 262. Through the coupling of the electron and the hole, light can be generated from the light-emitting layer 262. The light generated as described above can be discharged in a downward direction of the second substrate 200 through the second substrate 220.

[0085] According to embodiments of the inventive concept, the pressure applied to the pressure-sensitive display device can be converted into light. The pressure can be detected using an electrode of the light-emitting part 260. This means that the pressure-sensitive display device according to an embodiment of the inventive concept may not require an additional intermediate component (e.g., a driver circuit, etc.) that detects the pressure, converts the detected pressure into an electrical signal, and transmits the electrical signal back to the light-emitting part 260. This means that the pressure-sensitive display device can have a simple configuration and therefore a small thickness.Furthermore, since the intermediate member is not required, an electrical distance between the first substrate 100 for detecting pressure and the second substrate 200 for generating light can be small, and an electrical characteristic of the pressure-sensitive display device can be improved.

[0086] According to the embodiments, with increasing pressure applied to the first electrode 140, the amount of charge generated in the first electrode 140 may increase. For example, with increasing external pressure, the amount of charge generated in the first electrode 140 may increase, and the amount of light generated by the light-emitting layer 262 may increase. That is, the intensity of the generated light may be varied depending on the intensity of the external pressure, and the pressure-sensitive display device according to an embodiment of the inventive concept may measure the intensity of the external pressure using the light intensity.

[0087] The pressure-sensitive display device according to an embodiment of the inventive concept can generate light at a point on the second substrate corresponding to a point on the first substrate to which the pressure is applied. Fig. 12 to 14 are cross-sectional views for explaining an operating range of the pressure-sensitive display device according to the embodiments of the inventive concept.

[0088] In relation to Fig. 12, a first external input PRS1 may be applied to a first point CP1. For example, the first point CP1 may be a point on the first substrate 100 (or a point on the second substrate 200). The first external input PRS1 may include a touch by a user's finger or a touch by a stylus. The first substrate 100 may be deformed at the first point CP1 by the first external input PRS1. The first substrate 100 may touch the second substrate 200 at the first point CP1, and the first substrate 100 may be spaced apart from the second substrate 200 in the rest region except for the first point CP1. The first point CP1 may correspond perpendicular to the position where the first external input PRS1 is provided.Thus, a current flowing from the first electrode 140 through the light-emitting part 260 to the third electrode 240 can be generated at the first point CP1, and the first light LR1 can be discharged at the first point CP1 through the second sub-substrate 220. That is, a position where the first light LR1 is discharged may vertically correspond to a position of touch by a finger, a stylus, etc., and light may not be generated in the rest area where the first input PRS1 is not provided.

[0089] According to embodiments of the inventive concept, a circuit of the first electrode 140, the light-emitting part 260, and the third electrode 240 can be configured only at the location where the external input is applied. Thus, the light can be generated in real time at the position corresponding to the external input, and the position of the external input can precisely match the light generation position. That is, a pressure-sensitive display device with high sensitivity can be provided.

[0090] In relation to Fig. 13, a second external input PRS2 can be applied simultaneously to a plurality of second points CP2. For example, the second points CP2 can be a plurality of points spaced apart from each other on the first substrate 100. The second external input PRS2 can include a user's finger touch or a stylus touch. The first substrate 100 can be deformed at the second points CP2 by the second external input PRS2. The first substrate 100 can partially touch the second substrate 200 at the second points CP2, and the first substrate 100 can be spaced apart from the second substrate 200 in the rest area except for the second points CP2. The second points CP2 can correspond perpendicularly to the position where the second external inputs PRS2 are provided. Thus, the second light LR2 can be discharged through the second sub-substrate 220 at the second points CP2.That is, the positions where the second light LR2 is discharged may vertically correspond to the positions of touches by a finger, a stylus, etc., and no light is generated in the rest area where the second inputs PRS2 are not provided.

[0091] According to embodiments of the inventive concept, the first substrate 100 can be deformed only at the positions where the majority of external inputs are applied. Thus, the majority of external inputs can be easily detected, and the pressure-sensitive display device with high sensitivity can be provided.

[0092] In relation to Fig. 14, a third external input PRS3 may be applied to a contact surface CA with a large area. For example, the contact surface CA may be an area provided at a central part of the first substrate 100 (or an area provided at a central part of the second substrate 200). The third external input PRS3 may be provided by an element or an input device with a large area, such as a user's palm, a touch brush, or a touch panel. The first substrate 100 may be deformed on the contact surface CA by the third external input PRS3. Here, the first substrate 100 may be deformed according to the shape of the input device to which the third external input PRS3 is applied. For example, the first substrate 100 may contact the second substrate 200 over the entire contact surface CA.The contact area CA may overlap perpendicularly with a surface to which the third external input PRS3 is provided. Thus, a current flow flowing from the first electrode 140 through the light-emitting part 260 to the third electrode 240 may be provided over the entire contact area CA, and the third light LR3 may be discharged through the second sub-substrate 220 over the entire contact area CA. That is, a position where the third light LR3 is discharged may correspond to an area to which the third external input PRS3 is applied. When the external input is applied to a large area such as the contact area CA, a pressure applied to the first electrode 140 may be small. In this case, the third light LR3 generated in the light-emitting part 260 may have low brightness.

[0093] Fig. 15 to 16 are cross-sectional views for explaining a pressure-sensitive display device according to embodiments of the inventive concept.

[0094] In relation to Fig. 15, the pressure-sensitive display device may further include a third substrate 400 provided beneath the second substrate 200. The third substrate 400 may detect light generated in the second substrate 200. The third substrate 400 may include a third sub-substrate 420, an image sensor element 440, and a protective layer 460.

[0095] The third sub-substrate 420 may be a semiconductor substrate. For example, the third sub-substrate 420 may be a bulk silicon substrate, a silicon-on-insulator (SOI) substrate, a germanium substrate, a germanium-on-insulator (GOI) substrate, a silicon-germanium substrate, a group 3-5 compound semiconductor substrate, or a substrate made of a thin epitaxial layer obtained by selective epitaxial growth (SEG).

[0096] At least one image sensor element 440 may be provided on the third sub-substrate 420. The image sensor elements 440 may be provided on a top surface of the third sub-substrate 420. The image sensor elements 440 may be spaced apart from each other in a direction parallel to the top surface of the third sub-substrate 420. For example, the image sensor elements 440, although not shown, may be arranged in rows and columns on the third sub-substrate 420. The image sensor elements 440 may detect light emitted from points on the second substrate 200 according to their arrangement. Thus, the third sub-substrate 420 may detect a position of the first substrate 100 to which external pressure is applied and generate an electrical signal. The image sensor elements 440 may be a CMOS image sensor device or a charge-coupled device.For example, the image sensor elements 440 may include a photodiode or a transistor.

[0097] The protective layer 460 may be provided on the third sub-substrate 420. The protective layer 460 may cover the image sensor elements 440 on the upper surface of the third sub-substrate 420. An upper surface of the protective layer 460 may contact a lower surface of the second substrate 200. The protective layer 460 may contain a transparent insulating material.

[0098] According to other embodiments, the protective layer 460 may not be provided. For example, as in Fig. As shown in Figure 16, the third sub-substrate 420 may directly contact a lower surface of the second sub-substrate 220. Here, the image sensor elements 440 may be embedded in the second substrate 220.

[0099] Fig. 17 to 18 are cross-sectional views for explaining a method of manufacturing the pressure-sensitive display device according to the embodiments of the inventive concept.

[0100] In relation to Fig. 17, the second substrate 200 may be formed. For example, the second substrate 200 may be formed by sequentially laminating the third electrode 240 and the light-emitting part 260 onto the second substrate 220.

[0101] The second substrate 220 may be provided. The second sub-substrate 220 may be a transparent substrate. The second sub-substrate 220 may contain a transparent material. For example, the second sub-substrate 220 may contain glass, plastic, or elastomer.

[0102] The third electrode 240 may be disposed on the second sub-substrate 220. The third electrode 240 may include a transparent conductive material. For example, the transparent conductive material may include an indium tin oxide (ITO), an indium zinc oxide (IZO), or an oxide metal oxide (OMO) thin film.

[0103] The light-emitting layer 260 may be formed on the third electrode 240. In particular, the hole transport region 265 (see Fig. 3) on the third electrode 240. The hole transport region 265 can be formed by various methods, such as a vacuum deposition method, a spin coating method, a casting method, a Langmuir-Blodgett (LB) method, an injection printing method, a laser printing method, and a laser-induced thermal imaging (LITI) method. The light-emitting layer 262 (see Fig. 3) can be formed on the hole transport region 265. The light-emitting layer 262 can be formed by applying various methods such as a vacuum deposition method, a spin coating method, a casting method, a Langmuir-Blodgett (LB) method, an injection printing method, a laser printing method, and a laser-induced thermal imaging (LITI) method. The electron transport region 268 (see Fig. 3) can be formed on the light-emitting layer 262. The electron-transport region 268 can be formed using various methods, such as a vacuum deposition method, a spin coating method, a casting method, a Langmuir-Blodgett (LB) method, an injection printing method, a laser printing method, and a laser-induced thermal imaging (LITI) method. As described above, the light-emitting part 260 can be formed by sequentially laminating the hole-transport region 265, the light-emitting layer 262, and the electron-transport region 268 on the third electrode 240.

[0104] In relation to Fig. 18, the first substrate 100 may be formed. For example, the first substrate 100 may be formed by sequentially laminating the second electrode 160 and the first electrode 140 onto the first sub-substrate 120.

[0105] The first sub-substrate 120 may be provided. The first sub-substrate 120 may be a flexible substrate. The first sub-substrate 120 may include a flexible insulating material. For example, the first sub-substrate 120 may include polyimide (PI), polyethylene naphthalate (PEN), polycarbonate (PC), poly(ethersulfone) (PES), poly(ethylene terephthalate) (PET), poly(dimethyl sulfate) (PDMS), or Ecoflex.

[0106] The second electrode 120 may be formed on the first sub-substrate 120. The second electrode 160 may be formed by depositing or applying a conductive material to a surface of the first sub-substrate 120. For example, the conductive material may include a metal such as gold (Au), silver (Ag), copper (Cu), titanium (Ti), molybdenum (Mo), or aluminum (Al), or a conductive polymer such as poly-3,4-ethylenedioxythiophene:polystyrenesulfonate (PEDOT:PSS).

[0107] The first electrode 140 may be formed on the second electrode 160. The first electrode 140 may be formed by depositing a precursor material containing a nanostructure material onto the second electrode 160 and then curing the precursor material. Alternatively, the first electrode 140 may be formed by directly injecting or applying the nanostructure material to the second electrode 160.

[0108] According to another embodiment, the second electrode 160 may not be formed on the basis of necessity. For example, the first electrode 140 may be formed on a surface of the first sub-substrate 120. In this case, the pressure-sensitive display device according to the embodiment of Fig. 1. The method will be further described below with reference to a case of forming the second electrode 160.

[0109] The spacer 300 may be formed on the first substrate 100. The spacer 300 may be formed on the first electrode 140 of the first substrate 100. For example, the spacer 300 may be formed by forming an adhesive layer on the first electrode 140 and then removing a portion (320) of the adhesive layer. Here, an area from which the portion (320) of the adhesive layer is removed may be defined as a detection area for detecting external pressure in the pressure-sensitive display device. Alternatively, the spacer 300 may be formed by applying an adhesive tape to a partial surface of the first electrode 140.

[0110] In relation to Fig. 2 again, the first substrate 100 and the second substrate 200 can be bonded together. Specifically, the first substrate 100 and the second substrate 200 can be aligned such that the first electrode 140 of the first substrate 100 faces the light-emitting part 260 of the second substrate 200. The first substrate 100 and the second substrate 200 can be fixed with the spacer 300. Here, the second substrate 200 can be fixed to the first substrate 100 while being spaced apart from the first substrate 100. The pressure-sensitive display device according to the embodiment of Fig. 2 can be produced as described above.

[0111] Fig. 19 to 20 are cross-sectional views for explaining a method of manufacturing the pressure-sensitive display device according to the embodiments of the inventive concept.

[0112] In relation to Fig. 19, the third substrate 400 may be formed. For example, the image sensor elements 440 may be formed on the third sub-substrate 420.

[0113] The third sub-substrate 420 may be provided. The third sub-substrate 420 may be a semiconductor substrate. For example, the third substrate 420 may be a bulk silicon substrate, a silicon-on-insulator (SOI) substrate, a germanium substrate, a germanium-on-insulator (GOI) substrate, a silicon-germanium substrate, a group 3-5 compound semiconductor substrate, or a substrate made of a thin epitaxial layer obtained by selective epitaxial growth (SEG).

[0114] The image sensor elements 440 can be formed on the third sub-substrate 420. The plurality of image sensor elements 440 can be formed by performing a plurality of processes on a front surface of the third sub-substrate 420. The image sensor elements 440 can include a photodiode or a transistor. The transistor or photodiode can be formed by a fabrication process (FAB).

[0115] In relation to Fig. 20, the second substrate 200 may be formed on the third substrate 400. Specifically, the second substrate 200 may be formed by sequentially laminating the second sub-substrate 220, the third electrode 240, and the light-emitting part 260 on the third sub-substrate 420.

[0116] The second sub-substrate 220 can be formed. For example, the second sub-substrate 220 can be formed by depositing a transparent insulating material onto the third sub-substrate 420 and then curing the transparent insulating material. The transparent insulating material can be applied to cover the image sensor elements 440 on the third sub-substrate 420. For example, the transparent insulating material can include plastic or elastomer.

[0117] The third electrode 240 and the light-emitting part 260 may be formed on the second sub-substrate 220. A method for forming the third electrode 240 and the light-emitting part 260 may be the same as or similar to that described with respect to Fig. 17 described.

[0118] In relation to Fig. 15 again, the first substrate 100 may be mounted on the second substrate 200. For example, the first substrate 100 and the spacer 300 may be formed on the first substrate 100. A method for forming the first substrate 100 and the spacer 300 may be the same as or similar to that described with respect to Fig. 18. The first substrate 100 and the second substrate 200 can be bonded to each other. Specifically, the first substrate 100 and the second substrate 200 can be aligned such that the first electrode 140 of the first substrate 100 faces the light-emitting part 260 of the second substrate 200. The first substrate 100 and the second substrate 200 can be fixed by the spacer 300. Here, the second substrate 200 can be fixed to the first substrate 100 while being spaced apart from the first substrate 100. The pressure-sensitive display device according to the embodiment of Fig. 15 can be produced as described above.

[0119] According to other embodiments, the protective layer 460 may be formed on the third sub-substrate 420. The image sensor elements 440 may be formed on the third sub-substrate 420, and then the protective layer 460 may be formed on the third sub-substrate 420 to cover the image sensor elements 440. For example, the protective layer 460 may be formed by applying a transparent insulating material to the third sub-substrate 420 to cover the image sensor elements 440 and then curing the transparent insulating material. In this case, the pressure-sensitive display device according to the embodiment of Fig. 16 are produced.

[0120] The pressure-sensitive display device according to the embodiments of the inventive concept may not require the additional intermediate component for detecting pressure, converting the detected pressure into an electrical signal, and transmitting the electrical signal back to the light-emitting part. Therefore, the pressure-sensitive display device can have a simple configuration and a small thickness. Furthermore, since the intermediate component is not required, the electrical characteristics of the pressure-sensitive display device can be improved. Furthermore, the intensity of the generated light can be varied according to the intensity of the external pressure, and the pressure-sensitive display device can measure the intensity of the external pressure using the light intensity.

[0121] According to embodiments of the inventive concept, the pressure-sensitive display device can generate the light in real time at the position corresponding to the external input, and the position of the external input can precisely coincide with the generated position of the light. This means that the pressure-sensitive display device can be provided with high sensitivity. Furthermore, the pressure-sensitive display device can easily detect the majority of external inputs, and the pressure-sensitive display device with high sensitivity can be provided.

[0122] Although the exemplary embodiments of the present invention have been described, it is understood that the present invention should not be limited to these exemplary embodiments, but that various changes and modifications can be made by one of ordinary skill in the art within the spirit and scope of the present invention as claimed hereinafter. Therefore, the above-disclosed embodiments are to be considered illustrative and not restrictive.

Claims

[1] Pressure-sensitive display device comprising: a detection substrate (100); a reaction substrate (200) provided on the detection substrate; and spacers (300) provided between the detection substrate and the reaction substrate to space the detection substrate from the reaction substrate, wherein the sensing substrate comprises: a flexible substrate (120); and a touch electrode (140) provided on a surface of the flexible substrate facing the reaction substrate, and wherein the reaction substrate comprises: a transparent substrate (220); a transparent electrode (240) provided on a surface of the transparent substrate facing the detection substrate; and a light-emitting layer (262) disposed on the transparent electrode; and wherein each of the spacers has a columnar shape extending from an upper surface of the reaction substrate to a lower surface of the detection substrate, and wherein the spacers are arranged in rows and columns on the upper surface of the reaction substrate with respect to a plane. [2] A pressure-sensitive display device according to claim 1, wherein the detection substrate is deformed by an external pressure so that the touch electrode contacts the light-emitting layer, and the light-emitting layer emits light through the contact with the touch electrode. [3] A pressure-sensitive display device according to claim 2, wherein a contact area between the touch electrode and the light-emitting layer is substantially the same as a light-emitting area of ​​the light-emitting layer. [4] A pressure-sensitive display device according to claim 1, 2 or 3, wherein the touch electrode has flexibility. [5] A pressure-sensitive display device according to any one of claims 1 to 4, further comprising an intermediate electrode provided between the flexible substrate and the touch electrode. [6] A pressure sensitive display device according to claim 5, wherein the intermediate electrode has a greater resistance than the touch electrode. [7] A pressure-sensitive display device according to any one of claims 1 to 6, wherein the touch electrode has an electrical conductivity that gradually decreases in a direction away from the flexible substrate. [8] A pressure-sensitive display device according to any one of claims 1 to 7, wherein each of the spacers has a line shape extending in a direction parallel to an upper surface of the reaction substrate, and wherein the spacers are arranged in a strip shape or in the shape of an open ring provided on an outer part of the reaction substrate in a plane. [9] A pressure sensitive display device according to any one of claims 1 to 8, wherein the sensing substrate has a thickness of about 1 µm to about 20 µm. [10] A pressure-sensitive display device according to any one of claims 1 to 9, wherein the touch electrode comprises a nanowire, a nanofiber, a nanoparticle, a graphene or a nanotube. [11] The pressure-sensitive display device according to claim 10, wherein the touch electrode comprises a complex in which a nanostructure of a conductive material and a nanostructure of a non-conductive material are mixed. [12] A pressure-sensitive display device according to any one of claims 1 to 11, wherein the light-emitting layer comprises a quantum dot material or a perovskite material. [13] A pressure-sensitive display device according to any one of claims 1 to 12, further comprising an electron injection layer (266) provided on a first surface of the light-emitting layer facing the touch electrode, or a hole injection layer (263) provided on a second surface of the light-emitting layer facing the transparent electrode. [14] A pressure sensitive display device according to any one of claims 1 to 13, further comprising a photodiode or a transistor provided under the detection substrate. [15] A pressure-sensitive display device according to any one of claims 1 to 14, wherein the spacer comprises a non-conductive adhesive material, and wherein the touch electrode is fixed by the spacer while being spaced from the light-emitting layer. [16] Pressure-sensitive display device comprising: a transparent first substrate; a first electrode disposed on the first substrate; a light-emitting layer disposed on the first electrode; and a second electrode disposed on the light-emitting layer while being spaced from the light-emitting layer, wherein the second electrode comprises a flexible conductive material, and wherein the second electrode is deformed by external pressure to contact the light-emitting layer, and a part of the light-emitting layer contacting the touch electrode emits light; Spacers that define a space between the light-emitting layer and the second electrode, wherein each of the spacers has a columnar shape extending from an upper surface of the first substrate to a lower surface of the second substrate, and wherein the spacers are arranged in rows and columns on the upper surface of the first substrate with respect to a plane. [17] A pressure-sensitive display device according to claim 16, wherein each of the spacers has a line shape extending in a direction parallel to a top surface of the first substrate, and wherein the spacers are arranged in a strip shape or in the shape of an open ring provided on an outer part of the first substrate on a plane. [18] A pressure-sensitive display device according to any one of claims 16 to 17, further comprising a third electrode provided on the second substrate, the third electrode having a greater resistance than the second electrode. [19] A pressure-sensitive display device according to any one of claims 16 to 18, wherein the second electrode has an electrical conductivity that gradually decreases in a direction toward the light-emitting layer. [20] A pressure-sensitive display device according to any one of claims 16 to 19, wherein the pressure-sensitive display device further comprises a second substrate disposed on the second electrode, wherein the second substrate comprises a flexible substrate, and the second substrate in conjunction with the second electrode is deformed when the external pressure is applied. [21] A pressure-sensitive display device according to any one of claims 16 to 20, further comprising an electron injection layer provided on a first surface of the light-emitting layer facing the second electrode, or a hole injection layer provided on a second surface of the light-emitting layer facing the first electrode.

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