Infrared organic photoelectric sensor, array and chip

Abstract

The invention belongs to the technical field of photoelectric semiconductor devices, and particularly relates to an infrared organic photoelectric sensor, an array and a chip, the infrared organic photoelectric sensor is used for sensing light, and the sensor comprises a cathode, an electron transport layer, a photosensitive layer, a hole transport layer and an anode which are stacked in sequence; the electron mobility of the electron transport layer and the hole mobility of the hole transport layer meet the following relation: 0.01 < = [mu] h / [mu] e < = 100; wherein [mu] h represents the hole mobility of the hole transport layer, and [mu] e represents the electron mobility of the electron transport layer. Transmission, extraction and collection of carriers in a device are balanced by regulating and controlling the relation between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer, and then the sensitivity of the infrared organic photoelectric sensor and the imaging definition and resolution of a focal plane array device of the infrared organic photoelectric sensor are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of optoelectronic semiconductor devices, and more specifically, to an infrared organic photoelectric sensor, an array and a chip. Background Art

[0002] In organic optoelectronic devices, the electrode / organic semiconductor layer interface is the interface that plays a key role in device performance. Therefore, the introduction of a carrier transport layer can modify the electrode / organic semiconductor layer interface well, thus playing a vital role in improving device performance, and the carrier mobility of the carrier transport layer is one of the key factors affecting device performance. Carrier mobility is defined as the drift velocity of carriers per unit electric field strength, referred to as mobility, which is a parameter used to describe the speed of carrier transmission.

[0003] Therefore, it is particularly important to improve the performance of the device by regulating the carrier mobility of the carrier transport layer. Summary of the invention

[0004] The purpose of the present invention is to provide an infrared organic photoelectric sensor, array and chip, which balance the carrier transport, extraction and collection in the device by regulating the relationship between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer, thereby improving the sensitivity of the infrared organic photoelectric sensor and the imaging clarity and resolution of its focal plane array device.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] An infrared organic photoelectric sensor, the infrared organic photoelectric sensor is used for light sensing, the sensor comprises a cathode, an electron transport layer, a photosensitive layer, a hole transport layer, and an anode which are stacked in sequence;

[0007] The electron mobility of the electron transport layer and the hole mobility of the hole transport layer satisfy the following relationship:

[0008] 0.01≤μ h / μ e ≤100

[0009] Among them, μ h represents the hole mobility of the hole transport layer, μ e Represents the electron mobility of the electron transport layer.

[0010] The infrared organic photoelectric sensor generates excitons in the photosensitive layer when illuminated. After the excitons diffuse to the donor / acceptor interface in the photosensitive layer, the excitons are dissociated into free charges (electrons and holes). Then, carriers are transported through the hole transport layer HTL and the electron transport layer ETL, and finally, the charges are collected by the anode and cathode to form a current generated by photons.

[0011] Appropriate interfacial layers (hole transport layer, electron transport layer) are required to form low contact resistance between the photosensitive layer and the electrode to achieve efficient charge collection and to block the transport of opposite type carriers to achieve low dark current.

[0012] Generally, in a photoelectric sensor, excitons are dissociated into free charges (electrons and holes), which are transferred to the corresponding electrodes through the hole transport layer and the electron transport layer; if the carrier mobility of the hole transport layer and the electron transport layer differs too much, there may be a situation where the holes have been collected by the anode, while the electrons are still in the electron transport layer, which leads to a decrease in the sensitivity of the infrared organic photoelectric sensor, and even causes the readout circuit in the focal plane array device to be unable to effectively obtain the corresponding signal, thereby affecting the imaging clarity and resolution of the focal plane array device. The present invention regulates the relationship between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer, so that the difference between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer can be within a reasonable range, thereby ensuring and balancing the carrier transport, extraction and collection in the device, thereby improving the sensitivity of the infrared organic sensor and the imaging clarity and resolution of its focal plane array device. Generally, the smaller the difference between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer, the higher the sensitivity of the infrared organic photoelectric sensor and the imaging clarity and resolution of its focal plane array device.

[0013] It should be noted that the infrared organic photoelectric sensor may adopt a face-up structure or a face-down structure.

[0014] The inverted structure includes, from bottom to top, a substrate, a cathode close to the substrate, an electron transport layer, a photosensitive layer, a hole transport layer, an anode and an encapsulation layer.

[0015] The upright structure includes, from bottom to top, a substrate, an anode close to the substrate, a hole transport layer, a photosensitive layer, an electron transport layer, a cathode and an encapsulation layer.

[0016] The cathode and the anode can be formed of any conductive material.

[0017] If we list examples of the constituent materials of the electrodes (cathode, anode), we can cite: metals such as platinum, gold, silver, aluminum, chromium, nickel, copper, titanium, magnesium, calcium, barium, sodium, or their alloys; metal oxides such as indium oxide and tin oxide, or their composite oxides (such as indium tin oxide, indium zinc oxide); conductive polymers such as polyaniline, polypyrrole, polythiophene, and polyacetylene; those obtained by adding dopants such as hydrochloric acid, sulfuric acid, and sulfonic acid, Lewis acids such as FeCl3, halogen atoms such as iodine, and metal atoms such as sodium and potassium to the above conductive polymers; conductive composite materials in which conductive particles such as metal particles, carbon black, fullerene, and carbon nanotubes are dispersed in a matrix such as a polymer binder, etc. The constituent materials of the electrodes can be used alone or in combination of two or more in any combination and ratio.

[0018] Preferably, the electrode has a function of capturing holes and electrons generated in the photosensitive layer. Therefore, as the constituent material of the electrode, among the above materials, it is preferred to use a constituent material suitable for capturing holes and electrons. If electrode materials suitable for capturing holes are listed, for example, materials with high work functions such as silver and indium tin oxide can be cited. If electrode materials suitable for capturing electrons are listed, for example, materials with low work functions such as aluminum can be cited.

[0019] The incident light can be incident from the bottom or the top of the infrared organic photoelectric sensor.

[0020] For bottom-incident infrared organic photoelectric sensors, the cathode or anode close to the substrate is transparent or partially transparent in the required wavelength range, and the optical transmittance of the electrode is higher than 30%. The cathode or anode close to the substrate can be a transparent metal oxide (such as indium tin oxide, zinc oxide and aluminum-doped zinc oxide, etc.), or a nitride (such as titanium nitride) and a nitride oxide of the corresponding metal. In addition, the anode or cathode close to the encapsulation layer can be a thicker metal material, which can be, but is not limited to, aluminum, silver, titanium, tantalum, molybdenum, copper, chromium, gold and nickel.

[0021] For top-incident infrared organic photoelectric sensors, the cathode or anode close to the substrate can be used to reflect incident light in the required wavelength range to optimize the photosensitivity in a specific band. By selecting a suitable metal material, the required conductivity and optical reflectivity can be obtained at the same time. In addition, the anode or cathode close to the encapsulation layer is transparent or partially transparent in the required wavelength range, and the optical transmittance of the electrode is higher than 30%. In addition to thin metals and transparent metal oxides, the transparent or partially transparent anode or cathode close to the encapsulation layer can be realized with nano-metal particles or nano-metal wire mesh.

[0022] In this embodiment, the electrode is not limited in its formation method. The electrode can be formed, for example, by one or more dry processes selected from solution film formation, sol-gel film formation, vacuum thermal evaporation, atomic layer deposition, chemical vapor deposition, electrodeposition, and anodization.

[0023] The substrate may be formed of any material. When light is incident from the substrate side, it is necessary to be formed of a material with high transparency.

[0024] If we list examples of the constituent materials of the substrate, we can cite: inorganic materials such as glass, sapphire, and titanium dioxide; organic materials such as polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polyimide, nylon, polystyrene, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, fluororesin, vinyl chloride, polyethylene, cellulose, polyvinylidene chloride, aromatic polyamide, polyphenylene sulfide, polyurethane, polycarbonate, polyarylate, and polynorbornene; paper materials such as paper and synthetic paper; composite materials such as materials obtained by coating or laminating metals such as stainless steel, titanium, and aluminum with insulating properties, etc. The constituent materials of the substrate may be used alone or in combination of two or more in any combination and ratio.

[0025] The shape and size of the substrate are not limited and can be set arbitrarily. If the thickness of the substrate is too thin, the strength is insufficient and it cannot satisfy the function as a supporting member. If it is too thick, the cost increases. The substrate is usually in the form of a film or plate of about 10 μm to 50 mm.

[0026] The encapsulation layer is used to ensure that the infrared organic photoelectric sensor can work stably under various use environments and during the target life. If the infrared organic photoelectric sensor is bottom-incident, this encapsulation layer does not need to be optically transparent. If the infrared organic photoelectric sensor is top-incident, this encapsulation layer should be transparent in the working band and the optical transmittance should be above 30%.

[0027] The encapsulation layer can be formed by various vacuum coating methods, such as thermal evaporation, molecular beam coating or plasma sputtering, atomic layer deposition. It can also be prepared by liquid film forming methods, such as drop coating, dip coating, spin coating and various printing methods. In addition to selecting a single material, the encapsulation layer can also be formed by alternating multiple layers of film. In addition to improving the encapsulation performance, this alternating film structure can also be used to optimize the optical resonant cavity structure of the infrared organic photoelectric sensor in the working band, thereby optimizing its light sensitivity and specific detection rate.

[0028] Commonly used inorganic packaging materials include silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, zirconium oxide, magnesium oxide, zirconium oxide and magnesium fluoride. Commonly used organic packaging materials include polymethyl methacrylate, polyethylene oxide, polystyrene, polyvinyl pyrrolidone, polycarbonate, polyacrylic acid, epoxy resin, polyparaxylene and polysiloxazane.

[0029] The photosensitive layer comprises an organic semiconductor in the form of a single-phase film or a D / A bulk heterojunction blended film, an inorganic semiconductor or a compound semiconductor in the form of a single-phase or quantum dot nanoparticle, or a combination in a mixed form or a thin film stack; wherein D represents an organic donor material for an electron donor; and A represents an organic acceptor material for an electron acceptor;

[0030] Wherein, the inorganic semiconductor includes Si, Ge, SiGe, CuInS in crystalline or polycrystalline form. x Se 2-x (0≤x≤2), CuInGa(S,Se), PbS, PbI2, PBI3, InGaAs nano-quantum dots, nano-quantum thin films or single-phase films;

[0031] The organic semiconductor comprises an organic blend of one or more organic donor materials used as electron donors (D) and one or more organic acceptor materials used as electron acceptors (A) to form D / A.

[0032] The photosensitive layer can detect light in the wavelength range of 750nm to 2000nm.

[0033] The organic donor material may include one or more of the following:

[0034]

[0035] The organic receptor material may include one or more of the following:

[0036]

[0037] Preferably, the electron transport layer comprises several stacked electron transport sublayers; the electron mobility of the several electron transport sublayers gradually increases from the photosensitive layer to the cathode; the electron mobility of the electron transport layer is the mobility measured as a whole composed of the several electron transport sublayers.

[0038] The electron mobility of the multi-layer stacked electron transport sublayers gradually increases from the photosensitive layer to the cathode, which reduces the loss during electron transport, increases the electron transport rate, and improves the efficiency of electron transport to the cathode.

[0039] The electron transport layer of the present invention is provided with at least one electron transport sublayer, which can improve the photoelectric conversion efficiency and reduce the dark current. The LUMO difference between the electron transport sublayer and the acceptor material of the photosensitive layer is preferably less than 1.5 eV, preferably 1.0 eV.

[0040] Furthermore, the electron mobility of the electron transport sublayer close to the photosensitive layer is greater than the electron mobility of the acceptor material in the photosensitive layer.

[0041] The material of the electron transport sublayer includes an organic compound 1, an inorganic compound 1, or a combination thereof;

[0042] Wherein, the organic compound 1 includes fullerene and its derivatives, 4,7-diphenyl-1,10-phenanthroline, polyethyleneimine, polyethoxyethyleneimine, 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline,

[0043] [9,9-dioctylfluorene-9,9-bis(N,N-dimethylaminopropyl)fluorene], bromo-[9,9-dioctylfluorene-9,9-bis(N,N-dimethylaminopropyl)fluorene], 8-hydroxyquinoline lithium, 1,3,5-tri(1-phenyl-1H-benzimidazol-2-yl)benzene, bis(2-methyl-8-quinolinol)-4-(phenylphenol)aluminum, 1,3,5-tri[(3-pyridyl)-phenyl-3-yl]benzene, naphthalene diimide bromide, or a mixture or a complex thereof;

[0044] The inorganic compound 1 includes zinc oxide, tin oxide, aluminum-doped zinc oxide, magnesium-doped zinc oxide, gallium-doped zinc oxide, titanium oxide, tantalum oxide, zinc sulfide, chromium sulfide, or a mixture or composite of the above materials.

[0045] Preferably, the electron transport sublayer can be formed by a wet film forming method or a vacuum evaporation method, but the vacuum evaporation method is usually used.

[0046] The thickness of the electron transport sublayer ranges from 5nm to 200nm.

[0047] The change in the thickness of the electron transport layer will not only affect the charge transport of the device, but also affect the impedance characteristics of the device, thereby affecting the size of the photocurrent and the dark current.

[0048] Preferably, the hole transport layer comprises several stacked hole transport sublayers; the hole mobility of the several hole transport sublayers gradually increases from the photosensitive layer to the anode; the hole mobility of the hole transport layer is the hole mobility measured as a whole composed of the several hole transport sublayers.

[0049] The hole mobility of the multi-layered hole transport sublayer gradually increases from the photosensitive layer to the anode, which reduces the loss in the hole transport process, increases the hole transport rate, and improves the efficiency of hole transport to the anode. The hole transport layer includes at least one hole transport sublayer.

[0050] Furthermore, the hole mobility of the hole transport sublayer close to the photoactive layer is greater than the hole mobility of the donor material in the photoactive layer.

[0051] Further, the material of the hole transport sublayer includes organic compound 2, inorganic compound 2, or a combination thereof;

[0052] Wherein, the organic compound 2 includes 4,4'-cyclohexylbis[N,N'-bis(4-methylphenyl)aniline], N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-benzidine, N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-2,7-diamino-9,9-spirobifluorene, 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)amino]-9,9'- One or more of spirobifluorene, 4,4',4"-tri(carbazole-9-yl)triphenylamine, poly(4-butyltriphenylamine), polyvinylcarbazole, polystyrene-N,N'-diphenyl-N,N'-bis-(3-methylphenyl)-(1,1)-biphenyl-4,4'-diamineperfluorocyclobutane, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid), poly[bis(4-phenyl)(4-butylphenyl)amine];

[0053] The inorganic compound 2 includes tungsten oxide, molybdenum oxide, vanadium oxide, chromium oxide, nickel oxide, copper oxide, cuprous oxide, cuprous thiocyanate, copper sulfide, copper iodide, copper phthalocyanine, or a mixture or a composite of the above materials.

[0054] The preparation of the electron transport sublayer and the hole transport sublayer are independently selected from one or more of solution film formation, sol-gel film formation, vacuum thermal evaporation, atomic layer deposition, chemical vapor deposition, electrodeposition, and anodization.

[0055] The thickness of the hole transport sublayer ranges from 5nm to 200nm.

[0056] The electron mobility of the electron transport layer is in the range of 1.0×10 -5 cm 2 ·V -1 ·s -1 ~2.0×10 2 cm 2 ·V -1 ·s -1 The hole mobility ranges from 1.0×10 -5 cm 2 ·V -1 ·s -1 ~2.0×10 2 cm 2 ·V -1 ·s -1 .

[0057] The hole mobility of the hole transport layer of the present invention can be comprehensively regulated by adjusting the thickness of the hole transport layer and the selected materials. Similarly, the electron mobility of the electron transport layer can be comprehensively regulated by adjusting the thickness of the electron transport layer and the selected materials; so that the relationship between the hole mobility of the hole transport layer and the electron mobility of the electron transport layer satisfies the above relationship. Preferably, the relationship between the hole mobility of the hole transport layer and the electron mobility of the electron transport layer satisfies the following:

[0058] 0.02≤μ h / μ e ≤50

[0059] Among them, μ h represents the hole mobility of the hole transport layer, μ e Represents the electron mobility of the electron transport layer.

[0060] In the present invention, the thickness of the carrier transport layer (i.e., the electron transport layer, the hole transport layer) is positively correlated with the carrier mobility of the carrier transport layer; since the thicker the carrier transport layer, the longer the carrier transport distance, if the distance needs to be completed in the same time, the mobility of the electrons needs to be increased. Therefore, the thicker the carrier transport layer, the greater the required carrier mobility of the carrier transport layer. Similarly, the thickness of the hole transport layer is also positively correlated with the hole mobility of the hole transport layer.

[0061] Generally, the thickness of the electron transport layer and the hole transport layer are both smaller than the thickness of the photosensitive layer.

[0062] Generally, the optical band gaps of the electron transport layer and the hole transport layer are both greater than the lowest optical band gap of the photosensitive layer, preferably greater than 0.3 eV; the effective Fermi levels of the electron transport layer and the hole transport layer correspond to the energy levels of the corresponding charges in the photosensitive layer; for the electron transport layer, the energy level difference between the effective Fermi level of its electrons and the LUMO (sometimes called the lowest unoccupied molecular orbital in organic electronics) of the photosensitive layer is greater than -0.15 eV; for the hole transport layer, the energy level difference between the effective Fermi level of its holes and the HOMO (sometimes called the highest occupied molecular orbital in organic electronics) of the photosensitive layer is less than +0.15 eV. This energy level difference condition satisfies the effective transport of the corresponding charges at room temperature; the mobility of the electron transport layer and the hole transport layer in transporting the corresponding charges is greater than the mobility of the corresponding charges in the photosensitive layer, so as to satisfy the fact that the voltage drop on the photosensitive layer under working conditions is much greater than the voltage drop on the electron transport layer or the hole transport layer. Wherein, the charges are electrons or holes.

[0063] An infrared organic photoelectric sensor array comprises a plurality of picture elements, and the picture elements comprise the infrared organic photoelectric sensors.

[0064] Preferably, the infrared organic photoelectric sensor further comprises a substrate; the substrate comprises a pixel readout circuit composed of a silicon-based complementary metal oxide semiconductor transistor or a thin film transistor.

[0065] An infrared organic photoelectric sensor chip comprises the infrared organic photoelectric sensor array.

[0066] Compared with the prior art, the present invention has the following beneficial effects:

[0067] The present invention regulates the relationship between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer so that the difference between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer can be within a reasonable range, thereby ensuring and balancing the carrier transport, extraction and collection in the device, thereby improving the sensitivity of the infrared organic sensor and the imaging clarity and resolution of its focal plane array device. It effectively avoids the problem that the sensitivity of the infrared organic photoelectric sensor is reduced due to the large difference between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer, and even the readout circuit in the focal plane array device cannot effectively obtain the corresponding signal, thereby affecting the imaging clarity and resolution of the focal plane array device. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 It is a structural schematic diagram of an infrared organic photoelectric sensor provided by the present invention.

[0069] Figure 2 Schematic diagram of EQE of the infrared organic photoelectric sensor of Examples 1 and 2.

[0070] Figure 3 Schematic diagram of dark current of the infrared organic photoelectric sensor of Examples 1 and 2.

[0071] Figure 4 It is a schematic diagram of the responsivity of the infrared organic photoelectric sensor of Examples 1 and 2.

[0072] Figure 5 It is a schematic diagram of the specific detection rate of the infrared organic photoelectric sensor of Examples 1 and 2.

[0073] Figure 6 Schematic diagram of EQE of infrared organic photoelectric sensors of Examples 3 and 4.

[0074] Figure 7 Schematic diagram of dark current of the infrared organic photoelectric sensor of Examples 3 and 4.

[0075] Figure 8 It is a schematic diagram of the responsivity of the infrared organic photoelectric sensor of Examples 3 and 4.

[0076] Fig. 9It is a schematic diagram of the specific detection rate of the infrared organic photoelectric sensor of Examples 3 and 4.

[0077] Fig.10 Schematic diagram of EQE of the infrared organic photoelectric sensor of Examples 5 and 6.

[0078] Fig.11 Schematic diagram of dark current of the infrared organic photoelectric sensor of Examples 5 and 6.

[0079] Fig.12 It is a schematic diagram of the responsivity of the infrared organic photoelectric sensor of Examples 5 and 6.

[0080] Fig.13 It is a schematic diagram of the specific detection rate of the infrared organic photoelectric sensor of Examples 5 and 6.

[0081] Fig.14 It is a cross-sectional view of an infrared organic photoelectric sensor array provided in Example 7.

[0082] Fig.15 This is a top view of an infrared organic photoelectric sensor array provided in Example 7.

[0083] Fig.16 This is an imaging example diagram using the infrared organic photosensor array of Example 1.

[0084] Fig.17 This is an imaging example diagram using the infrared organic photosensor array of Example 2.

[0085] In the figure: 1- cathode, 2- electron transport layer, 3- photosensitive layer, 4- hole transport layer, 5- anode, 6- pixel, 7- packaging layer, 8- pixel readout circuit, 9- substrate, 10- infrared organic photoelectric sensor array. DETAILED DESCRIPTION

[0086] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The present invention is described in detail below in combination with the drawings and specific implementation methods.

[0087] It should be understood that when used in this specification, the terms "include" and "comprising" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or collections thereof.

[0088] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention, unless the context clearly indicates otherwise, the singular forms of "a", "an" and "the" are intended to include plural forms.

[0089] It should be further understood that the term “and / or” used in the specification of the present invention refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0090] Example 1

[0091] This embodiment provides an infrared organic photoelectric sensor, which is used for sensing light, such as Figure 1 As shown, the sensor includes a cathode, an electron transport layer, a photosensitive layer, a hole transport layer, and an anode which are stacked in sequence;

[0092] The cathode is made of indium tin oxide (ITO); the electron transport layer is made of zinc oxide (ZnO); the hole transport layer is made of copper phthalocyanine (CuPc); the anode is metallic silver; the photosensitive layer 3 adopts a bulk heterojunction structure, which is composed of a blend of an electron donor and two electron acceptors; the electron donor material is preferably NT812, and the electron acceptor material is organic molecules D1 and BTR. The mass ratio of NT812 to D1 and BTR is 1:1:0.5. D1 is: 2,2'-((12,13-bis(2-butyloctyl)-3,9-docosanyl-12,13-dihydro-[1,2,5]thiadiazo[3,4-e]thieno[2",3":4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole-2,10-diyl)bis(6,7-difluoro-4-oxonaphthalene-3(4H)-yl-1(4H)-ylidene))dicarbonitrile. It is disclosed in the patent "A short-wave infrared responsive deuterated quinone-terminated N-type organic molecule and a preparation method and application of a deuterated quinone-terminated end group, publication number: CN118290445A".

[0093] The preparation process of the infrared organic photoelectric sensor is as follows:

[0094] The ITO conductive substrate was ultrasonically treated and cleaned with isopropyl alcohol, detergent, deionized water, and acetone in sequence, with each treatment lasting 20 minutes. The cleaned ITO conductive substrate was then placed in an oven at 60° C. and dried for 5 hours; the ITO conductive substrate was then subjected to plasma surface treatment.

[0095] 50nm ZnO was prepared by magnetron sputtering with a sputtering power of 100W and a chamber pressure of 5mtorr.

[0096] The donor material NT812, the acceptor material D1 and BTR were blended in the above mass ratio and added into a mixed solvent of chlorobenzene and 1-chloronaphthalene (98:2, v / v) to make the concentration of NT812 be 10 mg / ml.

[0097] The mixture was stirred at 65°C for 4 hours, and then spin-coated onto the zinc oxide film at a rotation speed of 800 rpm for 1 minute, and thermally annealed at 100°C for 10 minutes to finally obtain a photosensitive layer film of a specified thickness.

[0098] In 5×10 -7 Under vacuum conditions of 20 torr, a 20 nm thick CuPC was deposited on the photosensitive layer by vacuum evaporation at a deposition rate of

[0099] In 5×10 -7 Under a vacuum condition of 0.04 torr, a silver film of a specified thickness is thermally evaporated and deposited on the CuPc film as an anode, thereby obtaining an infrared organic photoelectric sensor.

[0100] The mobility of the ZnO electron transport layer and the CuPc hole transport layer prepared by the above method was tested by a Hall effect tester; wherein the mobility μ of the electron transport layer was measured. e =0.47cm 2 / (V·s), mobility of hole transport layer μ h =1.47E-3cm 2 / (V·s), μ h / μ e =0.003.

[0101] Example 2

[0102] The difference between Example 2 and Example 1 is that the preparation process of the electron transport layer ZnO is changed, and the rest is consistent with Example 1.

[0103] Preparation of zinc oxide: 40 nm ZnO was prepared by the sol-gel method. 0.4 g of dihydrate and zinc acetate were dissolved in 4 mL of 2-methoxyethanol and 110 μL of ethanolamine mixed solvent and stirred overnight to obtain a ZnO precursor solution. The ZnO solution was then spin-coated on an ITO substrate and subsequently heated and annealed to obtain a 40 nm thick ZnO film.

[0104] The mobility of the ZnO electron transport layer and the CuPc hole transport layer prepared by the above method was tested by a Hall effect tester. The mobility μ of the electron transport layer was measured. e=1.98E-3cm 2 / (V·s), mobility of hole transport layer μ h =1.47E-3cm 2 / (V·s), μ h / μ e =0.742.

[0105] The EQE, dark current, responsivity, and specific detection rate of the infrared organic photoelectric sensors of Example 1 and Example 2 were measured. Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown. According to the measured EQE, dark current, responsivity, and specific detection rate, it can be known that when the electron mobility of the electron transport layer is closer to the hole mobility of the hole transport layer, the specific detection rate of the infrared organic photoelectric sensor is higher, the corresponding dark current is lower, and its sensitivity is higher. Conversely, when the difference between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer is greater, the specific detection rate of the infrared organic photoelectric sensor is lower, the corresponding dark current is higher, and its sensitivity is lower.

[0106] Example 3

[0107] This embodiment provides an infrared organic photoelectric sensor, which is used for sensing light, such as Figure 1 As shown, the sensor includes an anode, a hole transport layer, a photosensitive layer, an electron transport layer, and a cathode which are stacked in sequence;

[0108] The anode is made of indium tin oxide (ITO); the hole transport layer is made of copper iodide (CuI); the electron transport layer is made of fullerene (C60), the cathode is metallic silver, and the photosensitive layer 3 is made of a bulk heterojunction structure, which is composed of a blend of an electron donor and two electron acceptors. The electron donor material is preferably NT812, and the electron acceptor material is organic molecules D1 and BTR. The mass ratio of NT812 to D1 and BTR is 1:1:0.5. D1 is: 2,2'-((12,13-bis(2-butyloctyl)-3,9-docosanyl-12,13-dihydro-[1,2,5]thiadiazo[3,4-e]thieno[2",3":4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole-2,10-diyl)bis(6,7-difluoro-4-oxonaphthalene-3(4H)-yl-1(4H)-ylidene))dicarbonitrile. It is disclosed in the patent "A short-wave infrared responsive deuterated quinone-terminated N-type organic molecule and a preparation method and application of a deuterated quinone-terminated end group, publication number: CN118290445A".

[0109] The method for preparing the above-mentioned infrared organic photoelectric sensor comprises the following steps:

[0110] The ITO conductive substrate was ultrasonically treated and cleaned with isopropyl alcohol, detergent, deionized water, and acetone in sequence, with each treatment lasting 20 minutes. The cleaned ITO conductive substrate was then placed in an oven at 60° C. and dried for 5 hours; the ITO conductive substrate was then subjected to plasma surface treatment.

[0111] In 5×10 -7 Under vacuum conditions of 10 torr, 10 nm CuI was deposited on the above ITO substrate by vacuum evaporation at a deposition rate of

[0112] The donor material NT812, the acceptor material D1 and BTR were blended in the above mass ratio and added into a mixed solvent of chlorobenzene and 1-chloronaphthalene (98:2, v / v) to make the concentration of NT812 be 10 mg / ml.

[0113] The mixture was stirred at 65°C for 4 hours, and then spin-coated onto the zinc oxide film at a rotation speed of 800 rpm for 1 minute, and thermally annealed at 100°C for 10 minutes to finally obtain a photosensitive layer film of a specified thickness.

[0114] In 5×10 -7 Under vacuum conditions of 0.04 torr, 30 nm C60 was deposited on the above photosensitive layer by vacuum evaporation at a deposition rate of

[0115] In 5×10 -7 Under vacuum conditions of 0.1 torr, a silver film of a specified thickness is thermally evaporated and deposited on the fullerene film as a cathode, thereby obtaining an infrared organic photoelectric sensor.

[0116] The mobility of the fullerene electron transport layer and the CuI hole transport layer prepared by the above method was tested by a Hall effect tester, wherein the mobility μ of the electron transport layer was measured. e =3.31E-2cm 2 / (V·s), mobility of hole transport layer μ h =10.17cm 2 / (V·s),μ h / μ e =307.25

[0117] Example 4

[0118] The difference between Example 4 and Example 3 is that:

[0119] Magnesium-doped fullerene C60 is used as an electron transport layer to form a magnesium and fullerene C60 mixed layer. The doping ratio is controlled by the evaporation rate. The preferred evaporation rate is fullerene C60:Mg=2:1. Other preparations are consistent with Example 3.

[0120] Preparation of electron transport layer: A 30nm Mg and C60 mixed layer was prepared by vacuum evaporation. The Mg deposition rate was The deposition rate of C60

[0121] The mobility of the magnesium-doped fullerene electron transport layer and the CuI hole transport layer prepared by the above method was tested by a Hall effect tester. The mobility μ of the electron transport layer was measured. e =0.114cm 2 / (V·s), mobility of hole transport layer μ h =10.17cm 2 / (V·s),μ h / μ e =89.21.

[0122] The EQE, dark current, responsivity, and specific detection rate of the infrared organic photoelectric sensors of Example 3 and Example 4 were measured. Figure 6 , Figure 7 , Figure 8 , Fig. 9 As shown. According to the measured EQE, dark current, responsivity, and specific detection rate, it can be known that when the electron mobility of the electron transport layer is closer to the hole mobility of the hole transport layer, the specific detection rate of the infrared organic photoelectric sensor is higher, the corresponding dark current is lower, and its sensitivity is higher. Conversely, when the difference between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer is greater, the specific detection rate of the infrared organic photoelectric sensor is lower, the corresponding dark current is higher, and its sensitivity is lower.

[0123] Example 5

[0124] This embodiment provides an infrared organic photoelectric sensor, such as Figure 1 As shown, it includes an anode, a hole transport layer, a photosensitive layer, an electron transport layer, and a cathode which are stacked in sequence;

[0125] The anode is made of indium tin oxide (ITO); the hole transport layer is made of poly [bis (4-phenyl) (4-butylphenyl) amine] (Poly-TPD); the electron transport layer is made of naphthalene diimide bromide (NDI-Br), and the cathode is metallic silver; the photosensitive layer 3 adopts a bulk heterojunction structure, which is composed of a blend of an electron donor and two electron acceptors. The electron donor material is preferably NT812, and the electron acceptor material is the organic molecule D1 and BTR. And the mass ratio of NT812 to D1 and BTR is 1:1:0.5. D1 is: 2,2'-((12,13-bis(2-butyloctyl)-3,9-docosanyl-12,13-dihydro-[1,2,5]thiadiazo[3,4-e]thieno[2",3":4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole-2,10-diyl)bis(6,7-difluoro-4-oxonaphthalene-3(4H)-yl-1(4H)-ylidene))dicarbonitrile. It is disclosed in the patent "A short-wave infrared responsive deuterated quinone-terminated N-type organic molecule and a preparation method and application of a deuterated quinone-terminated end group, publication number: CN118290445A".

[0126] The method for preparing the above-mentioned infrared organic photoelectric sensor comprises the following steps:

[0127] The ITO conductive substrate was ultrasonically treated and cleaned with isopropyl alcohol, detergent, deionized water, and acetone in sequence, with each treatment lasting 20 minutes. The cleaned ITO conductive substrate was then placed in an oven at 60° C. and dried for 5 hours; the ITO conductive substrate was then subjected to plasma surface treatment.

[0128] 15nm Poly-TPD was prepared by spin coating and then drying. During the preparation of Poly-TPD, 10% by weight of photocrosslinker bisPFPA was added to the Poly-TPD solution, and after spin coating and drying, the Poly-TPD film was cured using an ultraviolet lamp to prevent the solvent from dissolving the Poly-TPD in the subsequent preparation process.

[0129] The donor material NT812, the acceptor material D1 and BTR were blended in the above mass ratio and added into a mixed solvent of chlorobenzene and 1-chloronaphthalene (98:2, v / v) to make the concentration of NT812 be 10 mg / ml.

[0130] The mixture was stirred at 65°C for 4 hours, and then spin-coated onto the zinc oxide film at a rotation speed of 800 rpm for 1 minute, and thermally annealed at 100°C for 10 minutes to finally obtain a photosensitive layer film of a specified thickness.

[0131] 10 nm NDI-Br was prepared by spin coating followed by drying.

[0132] In 5×10 -7 Under a vacuum condition of 0.1 torr, a silver film of a specified thickness is thermally evaporated and deposited on the electron transport layer film as a cathode, thereby obtaining an infrared organic photoelectric sensor.

[0133] The mobility of the NDI-Br electron transport layer and the Poly-TPD hole transport layer prepared by the above method was tested by a Hall effect tester; wherein the mobility μ of the electron transport layer was measured. e =2.6E-4cm 2 / (V·s), mobility of hole transport layer μ h =4.7E-4cm 2 / (V·s), μ h / μ e =1.81.

[0134] Example 6

[0135] The difference between Example 6 and Example 5 is that poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) (PEDOT:PSS) is used as the hole transport layer. The other preparations are the same as those in Example 5.

[0136] Preparation of the hole transport layer: 30 nm PEDOT:PSS was prepared by spin coating followed by drying.

[0137] The mobility of the NDI-Br electron transport layer and the PEDOT:PSS hole transport layer prepared by the above method was tested by a Hall effect tester; wherein the mobility μ of the electron transport layer was measured. e =2.6E-4cm 2 / (V·s), mobility of hole transport layer μ h =0.076cm 2 / (V·s), μ h / μ e =292.31.

[0138] The EQE, dark current, responsivity, and specific detection rate of the infrared organic photoelectric sensors of Example 5 and Example 6 were measured. Fig.10 , Fig.11 , Fig.12 , Fig.13As shown. According to the measured EQE, dark current, responsivity, and specific detection rate, it can be known that when the electron mobility of the electron transport layer is closer to the hole mobility of the hole transport layer, the specific detection rate of the infrared organic photoelectric sensor is higher, the corresponding dark current is lower, and its sensitivity is higher. Conversely, when the difference between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer is greater, the specific detection rate of the infrared organic photoelectric sensor is lower, the corresponding dark current is higher, and its sensitivity is lower.

[0139] Example 7

[0140] Based on the infrared organic photoelectric sensor provided in the above embodiment, an infrared organic photoelectric sensor array is also provided, such as Fig.14 , Fig.15 As shown, the infrared organic photoelectric sensor array 10 includes a plurality of picture elements 6, and the picture elements 6 include the infrared organic photoelectric sensors described in any one of Embodiments 2, 4, and 5.

[0141] In this embodiment, the infrared organic photoelectric sensor array 10 further includes a substrate 9; the substrate 9 includes a pixel readout circuit 8 composed of a silicon-based complementary metal oxide semiconductor transistor or a thin film transistor.

[0142] from Fig.15 As can be seen from the figure, the infrared organic photoelectric sensor array 10 includes, from bottom to top, a pixel readout circuit 9 made on a single crystal silicon substrate and composed of a silicon-based complementary metal oxide semiconductor transistor (MOSFET), and each pixel readout circuit is connected to a bottom electrode (here, cathode 1) array that defines the pixel size. Arranged on the bottom electrode array are an electron transport layer 2, a photosensitive layer 3, a hole transport layer 4, a top electrode (here, anode 5) and an encapsulation layer 7. From the electron transport layer 2, the photosensitive layer 3, the hole transport layer 4, the top electrode to the encapsulation layer 7, they are all continuous structures in the entire array area.

[0143] The infrared organic photoelectric sensor array of this embodiment is composed of N×M pixels, the size of the pixel 6 is 25 μm, and the number of pixels is 1×256 or 1×512. For example, the infrared organic photoelectric sensor array composed of the infrared organic photoelectric sensors of Embodiment 1 and Embodiment 2 is used for imaging test, wherein the imaging of the infrared organic photoelectric sensor array composed of the infrared organic photoelectric sensors of Embodiment 1 is as follows: Fig.16 As shown; the imaging of the infrared organic photoelectric sensor array composed of the infrared organic photoelectric sensor of Example 2, as shown Fig.17 shown; through Fig.16 , 17It can be seen that the difference between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer has an impact on the imaging clarity and resolution of the focal plane array device. The smaller the difference between the electron mobility of the electron transport layer and the hole mobility of the hole transport layer, the higher the imaging clarity.

[0144] In a specific embodiment, the electron transport layer 2 in the infrared organic photoelectric sensor array may also be configured as two electron transport sublayers, and the hole transport layer 4 may also be two hole transport sublayers.

[0145] When the electron transport layer 2 is configured as a multi-layer electron transport sublayer, each electron transport sublayer may be made of the same material or different materials; for the same material, different preparation processes may be used to form sublayers with mobility that meets the requirements. Similarly, the same is true for the hole transport layer.

[0146] Example 8

[0147] This embodiment further provides an infrared organic photoelectric sensor chip, which includes the infrared organic photoelectric sensor array described in Embodiment 7. The infrared organic photoelectric sensor chip is used for performing infrared photosensitive imaging.

[0148] The infrared organic photoelectric sensor chip described in this embodiment can be applied in the following aspects:

[0149] 1. It can be an industrial camera used to detect and identify defects, foreign matter, cracks and other problems on the surface of materials.

[0150] 2. It can also be used in medical diagnosis. Infrared light can penetrate the skin and other biological tissues, providing deeper details and resolution.

[0151] 3. It can also be used in food safety, specifically to detect contaminants, ingredients and quality in food.

[0152] 4. It can also be used in environmental monitoring to help monitor environmental parameters such as atmospheric pollutants, water quality and soil moisture content.

[0153] Obviously, the above embodiments of the present invention are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. An infrared organic photoelectric sensor, the infrared organic photoelectric sensor is used for light sensing, the sensor comprises a cathode, an electron transport layer, a photosensitive layer, a hole transport layer, and an anode stacked in sequence; Features: The electron mobility of the electron transport layer and the hole mobility of the hole transport layer satisfy the following relationship: 0.01≤μ h / m e ≤100 Among them, μ h represents the hole mobility of the hole transport layer, μ e Represents the electron mobility of the electron transport layer.

2. The infrared organic photoelectric sensor according to claim 1, characterized in that: The electron transport layer comprises a plurality of stacked electron transport sublayers; the electron mobility of the plurality of electron transport sublayers gradually increases from the photosensitive layer to the cathode; the electron mobility of the electron transport layer is the mobility measured as a whole composed of the plurality of electron transport sublayers.

3. The infrared organic photoelectric sensor according to claim 2, characterized in that: The electron mobility of the electron transport sublayer near the photoactive layer is greater than the electron mobility of the acceptor material in the photoactive layer.

4. The infrared organic photoelectric sensor according to claim 2, characterized in that: The material of the electron transport sublayer includes an organic compound 1, an inorganic compound 1, or a combination thereof; Wherein, the organic compound 1 includes fullerene and its derivatives, 4,7-diphenyl-1,10-phenanthroline, polyethyleneimine, polyethoxyethyleneimine, 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline, [9,9-dioctylfluorene-9,9-bis(N,N-dimethylaminopropyl)fluorene], bromo-[9,9-dioctylfluorene-9,9-bis(N,N-dimethylaminopropyl)fluorene], 8-hydroxyquinoline lithium, 1,3,5-tri(1-phenyl-1H-benzimidazol-2-yl)benzene, bis(2-methyl-8-quinolinol)-4-(phenylphenol)aluminum, 1,3,5-tri[(3-pyridyl)-phenyl-3-yl]benzene, naphthalene diimide bromide, or a mixture or a composite of the above materials; The inorganic compound 1 includes zinc oxide, tin oxide, aluminum-doped zinc oxide, magnesium-doped zinc oxide, gallium-doped zinc oxide, titanium oxide, tantalum oxide, zinc sulfide, chromium sulfide, or a mixture or composite of the above materials.

5. The infrared organic photoelectric sensor according to claim 2, characterized in that: The thickness of the electron transport sublayer ranges from 5 to 200 nm.

6. The infrared organic photoelectric sensor according to claim 1, characterized in that: The hole transport layer includes several stacked hole transport sublayers; the hole mobility of the several hole transport sublayers gradually increases from the photosensitive layer to the anode; the hole mobility of the hole transport layer is the hole mobility measured as a whole composed of the several hole transport sublayers.

7. The infrared organic photoelectric sensor according to claim 6, characterized in that: The hole mobility of the hole transport sublayer close to the photoactive layer is greater than the hole mobility of the donor material in the photoactive layer.

8. The infrared organic photoelectric sensor according to claim 6, characterized in that: The material of the hole transport sublayer includes an organic compound 2, an inorganic compound 2, or a combination thereof; Wherein, the organic compound 2 includes 4,4'-cyclohexylbis[N,N'-bis(4-methylphenyl)aniline], N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-benzidine, N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-2,7-diamino-9,9-spirobifluorene, 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)amino]-9,9'- One or more of spirobifluorene, 4,4',4"-tri(carbazole-9-yl)triphenylamine, poly(4-butyltriphenylamine), polyvinylcarbazole, polystyrene-N,N'-diphenyl-N,N'-bis-(3-methylphenyl)-(1,1)-biphenyl-4,4'-diamineperfluorocyclobutane, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid), poly[bis(4-phenyl)(4-butylphenyl)amine]; The inorganic compound 2 includes tungsten oxide, molybdenum oxide, vanadium oxide, chromium oxide, nickel oxide, copper oxide, cuprous oxide, cuprous thiocyanate, copper sulfide, copper iodide, copper phthalocyanine, or a mixture or a composite of the above materials.

9. The infrared organic photoelectric sensor according to claim 6, characterized in that: The thickness of the hole transport sublayer ranges from 5nm to 200nm.

10. The infrared organic photoelectric sensor according to claim 1, characterized in that: The electron mobility of the electron transport layer is in the range of 1.0×10 -5 cm 2 ·V -1 ·s -1 ~2.0×10 2 cm 2 ·V -1 ·s -1 The hole mobility ranges from 1.0×10 -5 cm 2 ·V -1 ·s -1 ~2.0×10 2 cm 2 ·V -1 ·s -1 .

11. An infrared organic photoelectric sensor array, characterized in that: The infrared organic photoelectric sensor array includes a plurality of picture elements, and the picture elements include the infrared organic photoelectric sensor as claimed in claim 1.

12. The infrared organic photoelectric sensor array according to claim 11, characterized in that: The infrared organic photoelectric sensor also includes a substrate; the substrate is a pixel readout circuit composed of a silicon-based complementary metal oxide semiconductor transistor or a thin film transistor.

13. An infrared organic photoelectric sensor chip, characterized in that: It comprises the infrared organic photosensor array as claimed in claim 11.

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