US-20260130039-A1 - LOW-VOLTAGE ORGANIC LIGHT-EMITTING SYNAPSE ELEMENT AND STIMULUS-SENSITIVE NEUROMORPHIC DISPLAY DEVICE COMPRISING SAME

Abstract

The present disclosure relates to an organic light-emitting layer having improved ion transport properties, an organic light-emitting synaptic device that may be driven at a low voltage, and a stimuli-responsive neuromorphic display device using the synaptic device capable of in-display signal processing that may receive signals from living body and environment and perform immediate visualization together with a bio-like signal processing process.

Inventors

• Tae Woo Lee
• Kwan Nyeong KIM
• Huan Yu ZHOU

Assignees

• SEOUL NATIONAL UNIVERSITY R&DB FOUNDATION

Dates

Publication Date

20260507

Application Date

20230519

Priority Date

20220520

Claims (20)

1. 1 . An organic light-emitting synaptic device comprising: an organic light-emitting layer including an organic light-emitting material and a plasticizer; an ionic dielectric layer; and two or more terminals, wherein the plasticizer includes a surfactant having both hydrophilicity and hydrophobicity, and the organic light-emitting synaptic device provides luminescence output and current output at the same time under an electrochemical doping-based driving principle.
2. 2 . The organic light-emitting synaptic device of claim 1 , which has at least one structure selected from the group consisting of a transistor, a diode, a resistor, a capacitor, an inductor, an ion pump, an ion cell (battery), a flash memory, a magnetic random access memory, a memristor, a resistive random access memory, a magnetoresistive random access memory and a phase-change memory.
3. 3 . The organic light-emitting synaptic device of claim 1 , wherein the organic light-emitting material is an organic molecule light-emitting material having a conjugation structure, an organic polymer light-emitting material having a conjugation structure, an organic/inorganic perovskite light-emitting material, or a mixture thereof.
4. 4 . The organic light-emitting synaptic device of claim 3 , wherein the organic small-molecule light-emitting material includes one selected from the group consisting of pentacene, TIPS-pentacene (6,13-bis(triisopropylsilylethynyl) pentacene), rubrene, tetracene, anthracene, triethylsilylethynyl anthradithiophene (TES ADT), (6,6)-phenyl-C61 butyric acid methyl ester (PCBM), fluorene, pyrene, tris(2-phenylpyridine)iridium (III) (Ir(ppy) 3 ), (2-phenylpyridine) (acetylacetonate iridium (III) (Ir(ppy) 2 (acac)), 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), spiro-OMeTAD (2,2′,7,7′-tetrakis (N,N-di-p-methoxyphenylamine) 9,9′-spirobifluorene), 2,2′-bipyridine (bpy), 1,10-phenanthroline (phen), perylene, poly(p-phenylene vinylene) (PPV) and combinations thereof.
5. 5 . The organic light-emitting synaptic device of claim 3 , wherein the organic polymer light-emitting material includes one selected from the group consisting of polythiophene, poly(3-hexylthiophene) (P3HT), poly(3-octylthiophene) (P30T), poly(butylthiophene) (PBT), poly(3,4-ethylenedioxythiophene) (PEDOT), poly(9-vinylcarbazole) (PVK), poly(p-phenylene vinylene), poly(thienylene vinylene) (PTV), polyacetylene, polyfluorene, polyaniline, polypyrrole, diketopyrrolopyrrole-based copolymers, isoindigo-based copolymers, derivatives thereof and combinations thereof.
6. 6 . The organic light-emitting synaptic device of claim 3 , wherein organic/inorganic perovskite light-emitting material includes one selected from the group consisting of formamidinium lead trihalide (FAPbX 3 , X═Cl, Br, I), methylammonium lead trihalide (MAPbX 3 , X═Cl, Br, I), phenethylammonium lead trihalide (PEAPbI 3 , X═Cl, Br, I), guanidinium lead thiocyanate (GAPb(SCN) 3 ), cesium lead bromide (CsPbBr 3 ), cesium lead iodide (CsPbI 3 ), cesium lead chloride/bromide (CsPb(Cl/Br) 3 ), cesium lead chloride/ iodide (CsPb(Cl/I) 3 ) and combinations thereof.
7. 7 . The organic light-emitting synaptic device of claim 1 , wherein the surfactant is a nonionic surfactant, an ionic surfactant or a mixture thereof.
8. 8 . The organic light-emitting synaptic device of claim 7 , wherein the nonionic surfactant includes one selected from the group consisting of polysorbate, polyethylene glycol (PEG), nonoxynol-9, octoxynol-9 (Triton X-100), alkyl polyglucoside (APG), ethylene oxide/propylene oxide copolymers, derivatives thereof and combinations thereof.
9. 9 . The organic light-emitting synaptic device of claim 7 , wherein the ionic surfactant includes one selected from the group consisting of sodium dodecyl sulfate (SDS), sodium lauryl sulfate (SLS), cetyltrimethylammonium bromide (CTAB), benzalkonium chloride (BAC), cocamidopropyl betaine (CAPB), sodium cocoyl isethionate (SCI), dioctyl sulfosuccinate (DOSS), sodium oleate, sodium stearate, sodium cholate, derivatives thereof and combinations thereof.
10. 10 . The organic light-emitting synaptic device of claim 1 , wherein the ionic dielectric layer includes an ionic dopant characterized in that cations and anions are separated by an applied electric signal.
11. 11 . The organic light-emitting synaptic device of claim 10 , wherein the ionic dopant includes cations of imidazolium, ammonium, pyrrolidinium, sulphonium, phosphonium, pyridinium and derivatives thereof; anions of chloride, iodide, bromide, sulfate, sulfonate, phosphate, phosphinate, aluminate, acetate, thiocyanate, dicyanamide, borate, antimonite, bis(sulfonyl) imide-based, tosylate, nitrate, decanoate, thiosalicylate, benzoate and derivatives thereof; or mixtures thereof.
12. 12 . The organic light-emitting synaptic device of claim 1 , which has a transistor structure including three or more terminals.
13. 13 . The organic light-emitting synaptic device of claim 12 , comprising: a gate electrode; the organic light-emitting layer forming a channel region; the ionic dielectric layer including an ionic dopant formed between the gate electrode and the channel region; a source electrode connected to the channel region; and a drain electrode connected to the channel region.
14. 14 . The organic light-emitting synaptic device of claim 13 , wherein the gate electrode controls electrochemical doping from the ionic dielectric layer to the channel region.
15. 15 . A stimuli-responsive neuromorphic display device comprising: at least one artificial sensory receptor circuit that senses stimuli; at least one artificial neuron circuit that receives a voltage signal from the artificial sensory receptor circuit, determines a threshold of the stimuli, and outputs a spike signal when breaking through the threshold; and the organic light-emitting synaptic device of any one of claims 1 to 14 accumulating the spike signal and visualizing it through luminescence.
16. 16 . The stimuli-responsive neuromorphic display device of claim 15 , wherein the artificial sensory receptor circuit includes at least one load resistor and at least one voltage source.
17. 17 . The stimuli-responsive neuromorphic display device of claim 15 , wherein the artificial sensory receptor circuit includes at least one sensor selected from the group consisting of a temperature sensor, a strain sensor or a pressure sensor, an optical sensor, an image sensor that senses visual information, an acceleration sensor that senses a balance, a gyroscope sensor and a gas sensor that senses chemical substances inside or outside a living body.
18. 18 . The stimuli-responsive neuromorphic display device of claim 17 , wherein the temperature sensor includes at least one temperature-sensitive resistive material selected from the group consisting of polymers; carbon nanotubes; carbon nanofibers; carbon black; graphene; graphene oxide; transition metal dichalcogenides; MXene; inorganic semiconductor membranes; metals having a nanostructure of one of nanoparticles, nanorods, nanowires and nanoflakes; and semiconducting nanowires.
19. 19 . The stimuli-responsive neuromorphic display device of claim 17 , wherein the temperature sensor is at least one selected from the group consisting of a piezoresistive strain sensor, a piezoelectric strain sensor, a triboelectric strain sensor and a capacitive strain sensor, which change an electric signal by changing resistance, current, voltage and permittivity according to thermal stimuli or changing optical properties by changing light transmittance and light absorptivity.
20. 20 . The stimuli-responsive neuromorphic display device of claim 15 , wherein the artificial neuron circuit includes a ring oscillator that changes the voltage signal into a spike form, and a comparator that determines whether the voltage signal breaks through a threshold.

Description

TECHNICAL FIELD The present disclosure relates to an organic light-emitting synaptic device including an organic light-emitting layer having improved ionic conductivity, and a stimuli-responsive neuromorphic display device using the device. The present specification claims priority to and the benefits of Korean Patent Application No. 10-2022-0061982, filed with the Korean Intellectual Property Office on May 20, 2022, the entire contents of which are incorporated herein by reference. BACKGROUND ART With the development of Internet of Things (IoT), metabus, AI and the like, current devices and systems using existing Von Neumann-based computing units are experiencing limitations in energy consumption and data processing speed. To address these challenges, neuromorphic devices and systems have emerged, designed to mimic the structure and operational principles of biological nervous systems for efficient signal processing, and synaptic devices have been developed as a neuromorphic computing unit. However, in order to realize Internet of Things (IoT), metabus and AI, interactions with users through displays are essential, and existing computing units or display control units are essential in order to process signals with synaptic devices and operate displays, which Causes limitations in energy consumption and data processing speed again. Accordingly, a new type of device is required to solve such limitations in display operation. A light-emitting synaptic device in which a synaptic device and a light-emitting device are integrated into a single device has both neuroplasticity properties of a synaptic device and light-emitting properties in the single device, thereby having advantages in device integration, energy consumption and data processing speed. A light-emitting transistor using an device structure of an organic light-emitting transistor has been reported recently (Yusheng Chen, Hanlin Wang, Yifan Yao, Ye Wang, Chun Ma, and Paolo Samor_*, Adv. Mater.2021, 33, 2103369), however, it has limitations in high voltage driving of an organic light-emitting transistor and complicated process for manufacturing charge transport layer/light-emitting layer/charge injection layer. Accordingly, in order to solve these limitations, development of a light-emitting synaptic device that enables low voltage driving and is manufacturable using a simple process, and development of a bio-signal processing system using the same have been required. PRIOR DOCUMENTS (Patent Document 1) KR 10-2019-0136419 A (Patent Document 2) KR 10-2019-0136402 A DISCLOSURE Technical Problem The present disclosure is directed to providing an organic light-emitting layer having improved ion transport properties in which an organic light-emitting material and a plasticizer are mixed, a method for manufacturing the organic light-emitting layer, and an organic light-emitting synaptic device employing the same providing luminescence output and current output at the same time under an electrochemical doping-based driving principle, and more specifically, providing an organic light-emitting synaptic device having a transistor structure that may be driven at a low voltage of 2.5 V or less by solving a problem such as high driving voltage of 30 V or greater of an existing organic light-emitting synaptic device having a transistor structure imitating a biological synaptic response. The present disclosure is also directed to providing a stimuli-responsive neuromorphic display device capable of in-display signal processing that may receive signals from a living body and environment and perform immediate visualization together with a bio-like signal processing process by using a light-emitting-type artificial nervous system formed with an artificial sensory receptor circuit, an artificial neuron circuit and an organic light-emitting synaptic device. The present disclosure is also directed to providing a stimuli-responsive neuromorphic display device capable of signal processing like biological nerves and synapses and immediate warning at the same time in response to a danger signal by driving a plurality of light-emitting pixels through a simple method using electrolyte gating of an organic light-emitting synaptic device having a transistor structure without an external computer or control circuit for driving the plurality of light-emitting pixels. However, objects to be addressed by the present disclosure are not limited to the object mentioned above, and other objects not mentioned will be clearly appreciated by those skilled in the art from the following description. Technical Solution One embodiment of the present disclosure provides an organic light-emitting synaptic device including: an organic light-emitting layer including an organic light-emitting material and a plasticizer; an ionic dielectric layer; and two or more terminals, wherein the plasticizer includes a surfactant having both hydrophilicity and hydrophobicity, and the organic light-emitting syna