[go: up one dir, main page]

CN111312902A - Flat panel detector structure and preparation method thereof - Google Patents

Flat panel detector structure and preparation method thereof Download PDF

Info

Publication number
CN111312902A
CN111312902A CN202010124606.1A CN202010124606A CN111312902A CN 111312902 A CN111312902 A CN 111312902A CN 202010124606 A CN202010124606 A CN 202010124606A CN 111312902 A CN111312902 A CN 111312902A
Authority
CN
China
Prior art keywords
layer
light conversion
interface layer
flat panel
panel detector
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010124606.1A
Other languages
Chinese (zh)
Inventor
罗宏德
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Iray Technology Co Ltd
Original Assignee
Iray Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Iray Technology Co Ltd filed Critical Iray Technology Co Ltd
Priority to CN202010124606.1A priority Critical patent/CN111312902A/en
Publication of CN111312902A publication Critical patent/CN111312902A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
    • H10K30/80—Constructional details
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K71/00—Manufacture or treatment specially adapted for the organic devices covered by this subclass
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K71/00—Manufacture or treatment specially adapted for the organic devices covered by this subclass
    • H10K71/60—Forming conductive regions or layers, e.g. electrodes
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/549—Organic PV cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Light Receiving Elements (AREA)
  • Solid State Image Pick-Up Elements (AREA)

Abstract

The invention provides a flat panel detector structure and a preparation method thereof, wherein the preparation method comprises the following steps: providing a substrate, preparing a lower electrode layer, dissolving a P-type organic photoelectric material and an N-type organic photoelectric material in an organic solvent to prepare a light conversion layer, and preparing a transparent conductive oxide film. The light conversion layer prepared from the organic photoelectric material can absorb short-wave and long-wave bands, improves the quantum efficiency of the device, can be dissolved in some organic solvents, enables the device to be processed by a solution method under a standard atmospheric pressure environment, abandons high vacuum and plasma equipment of the traditional semiconductor process, and is easy to form a film in a large area. The transparent upper electrode layer is prepared by adopting a sputtering method, so that the upper light transmission of the organic material-based device is realized, the photoelectric conversion efficiency of the device is improved, the damage of the preparation of the transparent upper electrode layer to the light conversion layer prepared from the organic photoelectric material is favorably prevented by arranging the sputtering barrier layer, the dark current of the device is reduced, and the photoelectric conversion efficiency is improved.

Description

Flat panel detector structure and preparation method thereof
Technical Field
The invention belongs to the technical field of ray detection, and particularly relates to a flat panel detector structure and a preparation method thereof.
Background
X-ray radiation imaging utilizes the characteristics of short wavelength and easy penetration of X-rays and different absorption characteristics of different substances to the X-rays, and imaging is carried out by detecting the intensity of the X-rays penetrating through an object.
The light conversion layer (also called photosensitive layer) material of the current commercial X-ray flat panel detector consists of amorphous silicon (A-Si), the A-Si process is mature, but the A-Si has two major problems: the process is complex, the investment is huge, and the matching between the A-Si photodiode light response and the scintillator light emission is not good. The amorphous silicon process is complex, particularly for a photodiode array, generally requires processes such as development, exposure, etching, PECVD (plasma enhanced chemical vapor deposition), sputtering and the like, a large number of masks are used in the process, and most of the processes require high vacuum and plasma equipment (such as dry etching, sputtering, PECVD and the like), so that the investment is large, the energy consumption is large, and the period is long. In actual detector operation, the amount of photodiode charge is proportional to the number of absorbed photons.
Ideally, the photodiodes should absorb photons emitted by the scintillator at equal proportions in different wavelength bands to maximize quantum efficiency. However, amorphous silicon photodiodes response is not uniform everywhere. Typical amorphous silicon photodiodes respond to light in the 300nm to 800nm band (full width at half maximum of about 200nm) with a peak response around 580 nm. It has a weak response in the near ultraviolet-blue region (300nm to 450nm) and red-near infrared (650nm to 750 nm). The most commonly used scintillator material in flat panel detectors is CsI: Tl (thallium doped cesium iodide), which has an emission spectrum with a Gaussian-like peak with a broad band emission from ultraviolet to near infrared (about 300nm to 800nm) with a peak at about 560 nm. The number of photons from 300nm to 450nm represents about 5% of the total number of emitted photons; the number of photons in the wavelength range of 650nm to 750nm accounts for about 16% of the total number of photons. From the above-mentioned response spectrum of amorphous silicon, photons with wavelengths of 300nm to 450nm and 650nm to 750nm cannot be efficiently absorbed by the photodiode. Meanwhile, the transmittance of visible light is not ideal, so that the photoelectric conversion efficiency of the device cannot be further improved.
Therefore, how to provide a flat panel detector structure and a manufacturing method thereof are necessary to solve the above problems in the prior art.
Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a flat panel detector structure and a manufacturing method thereof, which are used to solve the problems of short-wave and long-wave absorption defects of the flat panel detector in the prior art, and how to manufacture an X-ray flat panel detector structure of an upper transparent organic photoelectric conversion material array.
To achieve the above and other related objects, the present invention provides a method for manufacturing a flat panel detector structure, the method comprising the steps of:
providing a substrate, and preparing a lower electrode layer on the substrate;
dissolving a P-type organic photoelectric material and an N-type organic photoelectric material in an organic solvent to prepare a light conversion material solution, so as to form a light conversion layer on the lower electrode layer based on the light conversion material solution; and
and preparing an upper electrode layer on the light conversion layer, wherein the upper electrode layer comprises a transparent conductive oxide film.
Optionally, the P-type organic photoelectric material comprises at least one of P3HT and PCPDTBT; the N-type organic photoelectric material comprises at least one of PC61BM and PC71 BM; the organic solvent includes at least one of o-xylene, chloroform, and tetrahydronaphthalene.
Optionally, the light conversion layer is prepared based on a solution process, wherein the solution process comprises at least one of doctor blading, ink jet printing, screen printing, and slot coating.
Optionally, forming the transparent conductive oxide film by a sputtering method; the transparent conductive oxide thin film includes at least one of an ITO layer, an IZO layer, and an IWO layer.
Optionally, the step of forming the transparent conductive oxide thin film by a sputtering method includes: placing a sputtering target material vertically to the structure formed with the light conversion layer; setting the total pressure in the cavity between 0.1 Pa and 0.5 Pa; the current is between 5 and 10A; the voltage is between 300 and 400V; the total power of the sputtering plasma generator is between 1500 and 4000W; the ratio of Ar gas to oxygen gas is between 50/0.9 and 50/0.5; the distance from the target to the sample is between 200 and 400 mm; the sputtering rate is between 0.5 and 2 nm/s.
Optionally, the method further includes a step of forming a first interface layer after the light conversion layer is formed, where the first interface layer is formed on the upper surface of the light conversion layer, and the transparent conductive oxide film is formed on the first interface layer by a sputtering method.
Optionally, the step of forming the first interface layer includes: dispersing the quantum dots or nanoparticles of the first interface layer in a first solvent to form a first dispersion; and coating the first dispersion liquid on the light conversion layer by adopting a solution method to form the first interface layer.
Optionally, the material of the first interface layer comprises Se and MoO3、WO3、NiO、V2O5And at least one of PEDOT, PSS; the first solvent comprises at least one of water, ethanol, isopropanol and butanol; the solution method comprises at least one of blade coating, ink-jet printing, screen printing and slit coating; the thickness of the first interface layer is between 5nm and 100 nm.
Optionally, the method further includes a step of forming a second interface layer after forming the lower electrode layer, where the second interface layer is formed on the lower surface of the light conversion layer, and the transparent conductive oxide thin film is formed by a sputtering method after forming the second interface layer.
Optionally, the step of forming the second interface layer includes: dispersing the quantum dots or the nanoparticles of the second interface layer in a second solvent to form a second dispersion liquid; and coating the second dispersion liquid on the lower electrode layer by using a solution method to form the second interface layer.
Optionally, the material of the second interface layer comprises TiO2、ZnO、AZO、MZO、SnO2And PEIE; the second solvent comprises at least one of water, ethanol, isopropanol and butanol; the solution method comprises at least one of blade coating, ink-jet printing, screen printing and slit coating; the thickness of the second interface layer is between 10nm and 100 nm.
The invention also provides a flat panel detector structure, which is preferably prepared by the preparation method of the flat panel detector structure provided by the invention, and can be prepared by other methods, wherein the flat panel detector structure comprises the following components:
a substrate;
a lower electrode layer formed on the substrate;
a light conversion layer formed on the lower electrode layer, wherein the preparation raw materials of the light conversion layer comprise a P-type organic photoelectric material, an N-type organic photoelectric material and an organic solvent used for dissolving the P-type organic photoelectric material and the N-type organic photoelectric material;
and the upper electrode layer is formed on the light conversion layer and comprises a transparent conductive oxide film.
Optionally, the oxide semiconductor layer includes a transparent conductive oxide thin film prepared based on a sputtering process, the transparent conductive oxide thin film including at least one of an ITO layer, an IZO layer, and an IWO layer.
Optionally, the flat panel detector structure further includes a first interface layer, where the first interface layer is located on the upper surface of the light conversion layer; the material of the first interface layer comprises Se and MoO3、WO3、NiO、V2O5And at least one of PEDOT, PSS; the thickness of the first interface layer is between 5nm and 100 nm.
Optionally, the flat panel detector structure further includes a second interface layer, where the second interface layer is located on a lower surface of the light conversion layer; the material of the second interface layer comprises TiO2、ZnO、AZO、MZO、SnO2And PEIE; the thickness of the second interface layer is between 10nm and 100 nm.
As described above, the flat panel detector structure and the preparation method thereof can realize the absorption of short-wave and long-wave bands through the light conversion layer prepared from the organic photoelectric material, improve the quantum efficiency of the device, can be dissolved in some organic solvents, enable the device processing by a solution method under the standard atmospheric pressure environment to be possible, abandon the high vacuum and plasma equipment of the traditional semiconductor process, and are easy to form a film in a large area. In addition, the transparent upper electrode layer is prepared by adopting a sputtering method, so that the upper light transmission of the organic material-based device is realized, the photoelectric conversion efficiency of the device is improved, and the damage of the preparation of the transparent upper electrode layer to the light conversion layer prepared from the organic photoelectric material is favorably prevented by arranging the sputtering barrier layer, the dark current of the device is reduced, and the photoelectric conversion efficiency is improved.
Drawings
FIG. 1 is a schematic diagram of a process for fabricating a flat panel detector structure according to the present invention.
FIG. 2 is a schematic diagram of a substrate for fabricating a flat panel detector structure according to the present invention.
FIG. 3 is a schematic structural diagram of the formation of the lower electrode layer in the fabrication of the flat panel detector structure of the present invention.
FIG. 4 is a schematic structural diagram of a light conversion layer formed in the fabrication of the flat panel detector structure of the present invention.
FIG. 5 is a schematic structural diagram of an upper electrode layer formed in the fabrication of a flat panel detector structure according to the present invention.
FIG. 6 is a schematic structural diagram illustrating the formation of a first interface layer in the fabrication of a flat panel detector structure according to the present invention.
FIG. 7 is a schematic structural diagram illustrating the formation of a second interface layer in the fabrication of a flat panel detector structure according to the present invention.
FIG. 8 is a diagram illustrating a structure of a transparent conductive oxide film formed in the fabrication of a flat panel detector structure according to the present invention.
Fig. 9 is a schematic diagram of the structural connection of the flat panel detector according to an exemplary embodiment of the present invention.
Fig. 10 is a schematic diagram showing an equivalent circuit of a light conversion layer and a TFT layer of a flat panel detector according to an embodiment of the present invention.
Description of the element reference numerals
100 substrate
100a substrate
100b transistor functional layer
101 lower electrode layer
102 light conversion layer
103 upper electrode layer
104 first interface layer
105 second interface layer
106 transistor gate
107 transistor source
108 transistor drain
109 photodiode
110 readout line
111 scan line
S1-S3
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.
As in the detailed description of the embodiments of the present invention, the cross-sectional views illustrating the device structures are not partially enlarged in general scale for convenience of illustration, and the schematic views are only examples, which should not limit the scope of the present invention. In addition, the three-dimensional dimensions of length, width and depth should be included in the actual fabrication.
For convenience in description, spatial relational terms such as "below," "beneath," "below," "under," "over," "upper," and the like may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that these terms of spatial relationship are intended to encompass other orientations of the device in use or operation in addition to the orientation depicted in the figures. Further, when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present.
In the context of this application, a structure described as having a first feature "on" a second feature may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features are formed in between the first and second features, such that the first and second features may not be in direct contact.
It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the drawings only show the components related to the present invention rather than being drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of each component in actual implementation may be changed freely, and the layout of the components may be more complicated.
As shown in fig. 1, the present invention provides a method for manufacturing a flat panel detector structure, which includes the following steps:
providing a substrate, and preparing a lower electrode layer on the substrate;
dissolving a P-type organic photoelectric material and an N-type organic photoelectric material in an organic solvent to prepare a light conversion material solution, and preparing a light conversion layer on the lower electrode layer based on the light conversion material solution; and
and preparing an upper electrode layer on the light conversion layer, wherein the upper electrode layer comprises a transparent conductive oxide film.
The method for manufacturing the flat panel detector structure according to the present invention will be described in detail below with reference to the accompanying drawings.
As shown in S1 in fig. 1 and fig. 2-3, a substrate 100 is provided, and a lower electrode layer 101 is prepared on the substrate 100. The substrate 100 may include a glass substrate, and of course, may further include other functional layers required by the flat panel detector, and related structural layers in the flat panel detector structure may be manufactured on the substrate 100 according to actual requirements. Next, a lower electrode layer 101 is prepared on the substrate 100, and a material of the lower electrode layer 101 includes, but is not limited to, ITO (indium tin oxide) or Ag, and may be formed by sputtering or evaporation.
As an example, the substrate 100 includes a substrate 100a and a transistor functional layer 100b formed on the substrate 100a, wherein the transistor functional layer 100b includes a transistor source electrically connected to the lower electrode layer 101. Specifically, in an example, a structure of the substrate 100 is provided, which includes a substrate 100a and a Transistor functional layer 100b, in this example, the substrate 100a may be a glass substrate, and the Transistor functional layer 100b may be a TFT (thin film Transistor) layer, in this example, a Transistor source (source) (see the Transistor source 107 in fig. 9) in the TFT layer (as a switch layer) is electrically connected to the lower electrode layer 101, that is, the lower electrode layer 101 is electrically connected to the light conversion layer 102 for signal transmission, and of course, the Transistor functional layer further includes a Transistor gate and a Transistor drain, and in this example, the Transistor functional layers, such as the Transistor source layer and the Transistor drain layer in the TFT layer, and the lower electrode layer share the same material layer. Of course, the structure of each material layer of the transistor and the position relationship of the light conversion layer 102 can also be arranged and designed according to actual requirements.
As shown in S2 in fig. 1 and fig. 4, a P-type organic photoelectric material and an N-type organic photoelectric material are dissolved in an organic solvent to prepare a light conversion material solution, so as to form a light conversion layer 102 on the lower electrode layer 101 based on the light conversion material solution. The invention adopts an organic photoelectric conversion material to prepare a flat panel detector structure, the organic photoelectric conversion material is a photoelectric conversion device (OPD) prepared by using an organic semiconductor material, and an optical signal (photon) can be converted into a carrier (charge hole pair) to detect the optical signal. The organic semiconductor material is used to replace silicon-based photosensitive material (such as amorphous silicon and monocrystalline silicon) in the existing flat panel detector, and the novel flat panel detector is prepared. The flat panel detector based on the organic photoelectric material has the characteristics of simple structure and process, strong process compatibility, low cost, high sensitivity and the like, and can be applied to the fields of medical radiation imaging, industrial flaw detection, security inspection and the like. For organic photoelectric materials, the light response spectrum has wide coverage range, and particularly has stronger absorption in ultraviolet-blue light wave bands of 300nm to 450nm and deep red light-near infrared wave bands of 675nm to 750nm, so that the absorption of photons emitted by a scintillator is increased, and the quantum efficiency of a device is improved; can be dissolved in some organic solvents, so that the processing of the device by a solution method under the environment of standard atmospheric pressure becomes possible, and high vacuum, plasma and other equipment of the traditional semiconductor process are abandoned; and it is easy to form a film in a large area. The absorption of the short wave and the long wave by the photodiode is increased, and the external quantum efficiency of the photodiode can be increased. The sensitivity of the detector and the quantum detection efficiency DQE (detector quality factor) are increased, the ratio of the input signal-to-noise ratio (dose) to the output signal-to-noise ratio (image definition) on the spatial frequency expansion comprehensively reflects the performance advantages and disadvantages of the detector on the dose utilization rate and the spatial resolution, and also reflects that the radiation dose of a patient can be reduced.
As an example, the organic photovoltaic material consists of a P-type material (donor material) and an N-type material (acceptor material), which may be: p3HT (named: poly (3-hexylthiophene-2, 5-diyl)), and: PCPDTBT (the name is one or the combination of two or more of poly [2,6- (4, 4-bis- (2-ethylhexyl) -4H-cyclopenta [2, 1-b; 3, 4-b' ] dithiophene) -alt-4,7(2,1, 3-benzothiadiazole) ]); the N-type material can be: one or two or more of PC61BM (named [6,6] -phenyl C61 methyl butyrate) and PC71BM (named [6,6] -phenyl C71 methyl butyrate). In addition, in one example, the organic solvent includes at least one of o-xylene, chloroform, and tetralin. The light conversion material liquid can be prepared by weighing a P-type organic photoelectric material and an N-type organic photoelectric material according to a certain proportion, dissolving the materials in the organic solvent, and fully heating and stirring the materials.
As an example, the light conversion layer based on the organic photoelectric material is prepared by a solution method, and the light conversion material solution is coated on the lower electrode layer 101 by a solution method to form the light conversion layer 102, wherein the solution method comprises at least one of doctor blade coating, inkjet printing, screen printing and slot-die (slot-die), the light conversion layer is coated on the lower electrode layer 101 by the above method, the thickness of the layer is 100nm to 2000nm, and may be 500nm, 1000nm, and 1500nm, and after the coating, the layer may be dried in an oven at 80-120 ℃, for example 100 ℃, for 15-25min, for example 20 min. Wherein, the blade coating can be a method for manually coating by adopting a scraper and the like to prepare a material coating with required thickness, the extrusion type slit coating is a method for extruding the solution in a film head to the surface of a substrate by using certain pressure, drying is carried out after coating to form a required material film layer, the ink-jet printing can be a method for transferring the solution reagent to be sprayed to the surface of a structure to be processed after a spray head absorbs the solution reagent, and liquid drops are sprayed to the surface of the structure to be processed by the power of a sprayer in the forms of heat sensitivity, sound control and the like, thereby forming the material film layer with required thickness, the screen printing can be a method for printing by utilizing the basic principle that the mesh of the image-text part of a screen printing plate can permeate the solution reagent and the mesh of the non-image-text part can not permeate the solution reagent, the solution (the ray absorption material liquid) is poured, and simultaneously moving towards the other end of the screen printing plate at a constant speed, and extruding the solution onto a printing stock (the surface of a structure to be treated, such as the surface of the lower electrode layer) from meshes of the image-text part by a scraper in the movement.
As shown in S3 of fig. 1 and fig. 5, an upper electrode layer 103 is prepared on the light conversion layer 102, and the upper electrode layer 103 is a Transparent Conductive Oxide (TCO). As an example, the transparent conductive oxide thin film includes at least one of an ITO (indium tin oxide) layer, an IZO (indium zinc oxide) layer, and an IWO (tungsten-doped indium oxide) layer. For the flat panel detector adopting the organic photoelectric material to prepare the light conversion layer 102, the transparent upper electrode is difficult to effectively prepare on the flat panel detector, namely the upper light-transmitting flat panel detector structure is difficult to prepare, the scheme of light transmission at the bottom is adopted, light is transmitted through the bottom glass, and the photoelectric conversion efficiency of the device cannot be further improved because the glass has certain thickness and the detected light is attenuated; in addition, if a flat panel detector structure with upper light transmission is prepared, even if an ultra-thin electrode is adopted, such as an Ag electrode with a wavelength of 10nm or less, the visible light transmittance is not as ideal, and thus the photoelectric conversion efficiency of the device cannot be further improved. In one example, the transparent conductive oxide thin film is formed by a sputtering method, so as to prepare a flat panel detector structure with upper light transmission, for example, mirror target sputtering (mirror target sputtering). As an example, referring to fig. 8, the step of forming the transparent conductive oxide thin film using a sputtering method includes: placing the sputtering target and the sputtered sample vertically, where the sputtering sample may be a structure formed with the light conversion layer 102, placing the sputtering target and the sputtered sample vertically as shown in fig. 8, for example, placing the sputtered sample vertically, and placing the target horizontally, so that the target and the sample are placed vertically, in an example, the target: ITO or IZO; the total pressure in the cavity is as follows: 0.1-0.5 Pa; current: 5-10A, voltage: 300-400V; the total power of the sputtering plasma generator is 1500-4000W; ratio of Ar gas to oxygen gas: 50/0.9 to 50/0.5, and of course, Ar gas can be replaced by other inert gases; distance from target to sample: 200-400 mm, wherein the distance can be the distance between the end part of one end of the target material close to the sample and the surface of the sample; sputtering rate: 0.5-2 nm/s; the sputtering time was calculated from the film thickness: film thickness/sputtering rate, which can give ITO/IZO thin films of 100nm thickness. In this case, the generated plasma cannot directly reach the surface of the sample, so that plasma damage generated during sputtering is reduced, low-damage sputtering is performed, and the problem that high-energy plasma (for example, the energy range of the plasma is approximately distributed in 50-100 eV) directly bombards the organic thin film of the sputtered sample to cause serious damage when the sputtering target is placed in parallel with the sputtered sample for sputtering can be prevented. The process can be beneficial to preventing the damage of high-energy plasma to the organic layer below, such as the light conversion layer, and preventing the failure of the organic layer when the transparent conductive oxide film is formed by magnetron sputtering.
As an example, as shown in fig. 6, after the light conversion layer 102 is formed, a step of forming a first interface layer 104 is further included, where the first interface layer 104 is formed on the upper surface of the light conversion layer 102, and the transparent conductive oxide thin film is formed on the first interface layer 104 by a sputtering method. In the invention, a first interface layer 103 is prepared on the light conversion layer 102 to solve the problem that sputtering damages the light conversion layer 103 at the lower layer, so that a transparent upper electrode is prepared on the light conversion layer prepared from an organic photoelectric material. In an example, the transparent conductive oxide film is selected to be a low-damage transparent conductive oxide film, and in this example, the first interface layer 104 combines with the foregoing sputtering manner in which the sputtering target and the sputtered sample are vertically arranged, so that damage of plasma to the light conversion layer 102 can be effectively reduced.
As an example, the step of forming the first interface layer 103 includes: dispersing the quantum dots or nanoparticles of the first interface layer in a first solvent to form a first dispersion; and coating the first dispersion liquid on the light conversion layer by adopting a solution method to form the first interface layer. Optionally, the solution process comprises at least one of doctor blading, ink jet printing, screen printing, and slot coating. The thickness of the first interface layer 103 is, for example, between 5nm and 100nm, and may be, for example, 8nm, 20nm, 50nm, 80nm, or the like. Alternatively, the film may be dried in an oven at 80-120 deg.C, such as 100 deg.C, for 2-8 minutes, such as 5 minutes, after coating.
As an example, the first interface layer 103 is designed to serve as a sputtering blocking layer and also serve as a hole transport layer when the device operates, the hole transport layer, that is, an electron blocking layer, can realize transport of carrier holes and block electron transport, and the hole transport layer separates carriers in an organic photosensitive material film layer (the light conversion layer) so that the carriers can reach an electrode, thereby avoiding recombination of the carriers in the film layer and improving quantum efficiency; the reverse injection of charges is prevented, the dark current is reduced, and the sensitivity and the image contrast of the device are improved; the presence of the hole transport layer may also lower the work function at the interface of the light conversion layer. As an example, the material of the first interface layer 103 includes Se, MoO3、WO3、NiO，V2O5At least one of PSS (named as poly (3, 4-ethylenedioxythiophene) -poly (styrenesulfonate)); the first solvent comprises waterEthanol, isopropanol, and butanol.
As an example, as shown in fig. 7, after the lower electrode layer 101 is formed, a step of forming a second interface layer 105 is further included, the second interface layer 105 is formed on the lower surface of the light conversion layer 102, and the transparent conductive oxide thin film is formed by a sputtering method after the second interface layer 105 is formed, in this example, after the first interface layer 103 and the second interface layer 105 are formed, the transparent conductive oxide thin film is formed by a sputtering process, that is, a sputtering barrier layer is formed on both the upper and lower sides of the light conversion layer 102.
As an example, the step of forming the second interface layer 105 includes: dispersing the quantum dots or nanoparticles of the second interface layer 105 in a second solvent to form a second dispersion; the second dispersion liquid is coated on the lower electrode layer 101 using a solution method to form the second interface layer. As an example, the solution method includes at least one of doctor blade coating, inkjet printing, screen printing, and slit coating; the thickness of the second interface layer is, for example, between 10nm and 100nm, and may be, for example, 15nm, 20nm, 60nm, 80nm, or the like. Optionally, the film is dried in an oven at 80-120 deg.C, such as 100 deg.C, for 8-15 minutes, such as 10 minutes, after coating.
As an example, the second interface layer 105 is designed to be a material so that it can simultaneously serve as an electron transport layer when the device operates, the electron transport layer, that is, a hole blocking layer, can transport carrier electrons while blocking hole transport, the electron transport layer separates carriers in an organic photosensitive material film layer (the light conversion layer), so that the carriers can reach an electrode, recombination of the carriers in the film layer is avoided, and quantum efficiency is improved; the reverse injection of charges is prevented, the dark current is reduced, and the sensitivity and the image contrast of the device are improved; the presence of the electron transport layer may also lower the work function at the interface of the light conversion layer. As an example, the material of the second interface layer includes TiO2ZnO, AZO (Al-doped ZnO), MZO (Mg-doped ZnO), SnO2And PEIE (name: ethoxylated polyethyleneimine); as an example, allThe second solvent includes at least one of water, ethanol, isopropanol, and butanol.
For the structure prepared by the method for preparing the flat panel detector structure in an example of the present invention, the working process can be shown in fig. 9 and fig. 10, the upper electrode layer 103 of the device is connected to the negative electrode of the dc power supply, the lower electrode layer 101 is electrically connected to the positive electrode of the power supply, and the electric field strength can be set according to the actual setting, for example, 1 to 10V/um; in the absence of external X-ray, electrons and holes are depleted in the light conversion layer 102 (photosensitive layer prepared based on organic photoelectric material), theoretically no current is generated; when the device receives X-ray exposure (as shown in FIG. 9), the invention adopts an upper light transmission mode, and X-rays are matched with a scintillator to ionize the light conversion layer material to generate photon-generated carriers (electron hole pairs); under the action of an electric field, the holes drift towards the upper electrode layer, and the electrons drift towards the lower electrode layer; however, a small amount of electrons drift toward the upper electrode, and a small amount of holes drift toward the lower electrode; the lower electrode layer is connected to a TFT source (source), i.e., a transistor source 107, as shown in fig. 10, so that electrons are transferred to the lower electrode layer, then transferred to the TFT source, and stored in the TFT source; when the TFT is turned on (when the voltage of the gate electrode 106 of the transistor is greater than the threshold voltage of the TFT, the TFT is in an on state, and the source electrode 107 and the drain electrode 108 of the transistor are turned on), electrons are transferred from the source electrode of the transistor to the drain electrode (drain) of the transistor, and then transferred to the "readout line 110" and read by an external circuit, and in addition, the equivalent circuit diagram further includes a signal control scan line 109, the same operation is performed for each pixel (the combination of one photodiode and one TFT transistor in fig. 10 is called as one pixel), and the gray scale of the final image depends on the amount of charges in the corresponding pixel (for example, the more charges are stored, the higher the gray scale value is, the brighter the corresponding pixel point is).
In addition, as shown in fig. 7, referring to fig. 1 to 6 and fig. 8 to 10, the present invention further provides a flat panel detector structure, which is preferably prepared by the method for preparing a flat panel detector structure provided by the present invention, and of course, may also be prepared by other methods, where the flat panel detector structure includes:
a substrate 100;
a lower electrode layer 101 formed on the substrate 100;
a light conversion layer 102 formed on the lower electrode layer 101, wherein raw materials for preparing the light conversion layer 102 include a P-type organic photoelectric material, an N-type organic photoelectric material, and an organic solvent for dissolving the P-type organic photoelectric material and the N-type organic photoelectric material; and
and an upper electrode layer 103 formed on the light conversion layer 102, wherein the upper electrode layer 103 includes a transparent conductive oxide film.
As an example, the oxide semiconductor layer includes a transparent conductive oxide thin film prepared based on a sputtering process; the transparent conductive oxide thin film includes at least one of an ITO layer, an IZO layer, and an IWO layer.
By way of example, the flat panel detector structure further includes a first interface layer 104, and the first interface layer 104 is located on the upper surface of the light conversion layer 102.
As an example, the material of the first interface layer 104 includes Se, MoO3、WO3、NiO、V2O5And at least one of PEDOT, PSS; the thickness of the first interface layer 104 is between 5nm and 100 nm.
As an example, the flat panel detector structure further includes a second interface layer 105, and the second interface layer 105 is located on the lower surface of the light conversion layer 102.
As an example, the material of the second interface layer 105 includes TiO2、ZnO、AZO、MZO、SnO2And PEIE; the thickness of the second interface layer 105 is between 10nm and 100 nm.
The related features and descriptions of the flat panel detector structure of the present invention can refer to the related descriptions in the manufacturing process of the flat panel detector structure of the present invention, and are not described herein again.
In summary, the flat panel detector structure and the preparation method thereof of the invention can realize the absorption of short-wave and long-wave bands through the light conversion layer prepared from the organic photoelectric material, improve the quantum efficiency of the device, and can be dissolved in some organic solvents, so that the processing of the device by a solution method under a standard atmospheric pressure environment becomes possible, the high vacuum and plasma equipment of the traditional semiconductor process is abandoned, and the large-area film forming is easy. In addition, the transparent upper electrode layer is prepared by adopting a sputtering method, so that the upper light transmission of the organic material-based device is realized, the photoelectric conversion efficiency of the device is improved, and the damage of the preparation of the transparent upper electrode layer to the light conversion layer prepared from the organic photoelectric material is favorably prevented by arranging the sputtering barrier layer, the dark current of the device is reduced, and the photoelectric conversion efficiency is improved. Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.

Claims (15)

1. A method for manufacturing a flat panel detector structure is characterized by comprising the following steps:
providing a substrate, and preparing a lower electrode layer on the substrate;
dissolving a P-type organic photoelectric material and an N-type organic photoelectric material in an organic solvent to prepare a light conversion material solution, and preparing a light conversion layer on the lower electrode layer based on the light conversion material solution; and
and preparing an upper electrode layer on the light conversion layer, wherein the upper electrode layer comprises a transparent conductive oxide film.
2. The method for preparing a flat panel detector structure according to claim 1, wherein the P-type organic photoelectric material comprises at least one of P3HT and PCPDTBT; the N-type organic photoelectric material comprises at least one of PC61BM and PC71 BM; the organic solvent includes at least one of o-xylene, chloroform, and tetrahydronaphthalene.
3. The method of claim 1, wherein the light conversion layer is prepared based on a solution method, wherein the solution method comprises at least one of knife coating, ink-jet printing, screen printing, and slit coating.
4. The method for manufacturing a flat panel detector structure according to any one of claims 1 to 3, wherein the transparent conductive oxide thin film is formed by a sputtering method; the transparent conductive oxide thin film includes at least one of an ITO layer, an IZO layer, and an IWO layer.
5. The method for preparing a flat panel detector structure according to claim 4, wherein the step of forming the transparent conductive oxide thin film by sputtering comprises: placing a sputtering target material vertically to the structure formed with the light conversion layer; setting the total pressure in the cavity between 0.1 Pa and 0.5 Pa; the current is between 5 and 10A; the voltage is between 300 and 400V; the total power of the sputtering plasma generator is between 1500 and 4000W; the ratio of Ar gas to oxygen gas is between 50/0.9 and 50/0.5; the distance from the target to the sample is between 200 and 400 mm; the sputtering rate is between 0.5 and 2 nm/s.
6. The method for manufacturing a flat panel detector structure according to claim 4, further comprising a step of forming a first interface layer after forming the light conversion layer, wherein the first interface layer is formed on the upper surface of the light conversion layer, and the transparent conductive oxide film is formed on the first interface layer by a sputtering method.
7. The method of claim 6, wherein the step of forming the first interface layer comprises: dispersing the quantum dots or nanoparticles of the first interface layer in a first solvent to form a first dispersion; coating the first dispersion on the light conversion layer based on a solution method to form the first interface layer.
8. The method of claim 7, wherein the first interface layer comprises Se, MoO3、WO3、NiO、V2O5And at least one of PEDOT, PSS; the first solvent comprises at least one of water, ethanol, isopropanol and butanol; the solution method comprises at least one of blade coating, ink-jet printing, screen printing and slit coating; the thickness of the first interface layer is between 5nm and 100 nm.
9. The method for manufacturing a flat panel detector structure according to claim 6, wherein the step of forming the lower electrode layer further comprises a step of forming a second interface layer, the second interface layer is formed on the lower surface of the light conversion layer, and the transparent conductive oxide film is formed by a sputtering method after the second interface layer is formed.
10. The method of claim 9, wherein the step of forming the second interface layer comprises: dispersing the quantum dots or the nanoparticles of the second interface layer in a second solvent to form a second dispersion liquid; coating the second dispersion liquid on the lower electrode layer based on a solution method to form the second interface layer.
11. The method of claim 10, wherein the second interface layer comprises TiO2、ZnO、AZO、MZO、SnO2And PEIE; the second solvent comprises at least one of water, ethanol, isopropanol and butanol; the solution method comprises at least one of blade coating, ink-jet printing, screen printing and slit coating; the thickness of the second interface layer is between 10nm and 100 nm.
12. A flat panel detector structure, comprising:
a substrate;
a lower electrode layer formed on the substrate;
the light conversion layer is formed on the lower electrode layer, and the preparation raw materials of the light conversion layer comprise a P-type organic photoelectric material, an N-type organic photoelectric material and an organic solvent for dissolving the P-type organic photoelectric material and the N-type organic photoelectric material;
and the upper electrode layer is formed on the light conversion layer and comprises a transparent conductive oxide film.
13. The flat panel detector structure according to claim 12, wherein the oxide semiconductor layer comprises a transparent conductive oxide thin film prepared based on a sputtering process, the transparent conductive oxide thin film comprising at least one of an ITO layer, an IZO layer, and an IWO layer.
14. The flat panel detector structure of claim 13, further comprising a first interface layer located on an upper surface of the light conversion layer; the material of the first interface layer comprises Se and MoO3、WO3、NiO、V2O5And at least one of PEDOT, PSS; the thickness of the first interface layer is between 5nm and 100 nm.
15. The flat panel detector structure according to claim 14, further comprising a second interface layer located on a lower surface of the light conversion layer; the material of the second interface layer comprises TiO2、ZnO、AZO、MZO、SnO2And PEIE; the thickness of the second interface layer is between 10nm and 100 nm.
CN202010124606.1A 2020-02-27 2020-02-27 Flat panel detector structure and preparation method thereof Pending CN111312902A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010124606.1A CN111312902A (en) 2020-02-27 2020-02-27 Flat panel detector structure and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010124606.1A CN111312902A (en) 2020-02-27 2020-02-27 Flat panel detector structure and preparation method thereof

Publications (1)

Publication Number Publication Date
CN111312902A true CN111312902A (en) 2020-06-19

Family

ID=71145377

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010124606.1A Pending CN111312902A (en) 2020-02-27 2020-02-27 Flat panel detector structure and preparation method thereof

Country Status (1)

Country Link
CN (1) CN111312902A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112490334A (en) * 2020-11-06 2021-03-12 奕瑞影像科技（太仓）有限公司 Manufacturing method of X-ray flat panel detector and X-ray flat panel detector
CN112736201A (en) * 2020-12-30 2021-04-30 奕瑞影像科技（太仓）有限公司 Indirect flat panel detector and preparation method thereof
CN112802871A (en) * 2020-12-30 2021-05-14 奕瑞影像科技（太仓）有限公司 Organic photoelectric flat panel detector

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110095266A1 (en) * 2008-06-25 2011-04-28 Oliver Hayden Photodetector and method for the production thereof
US20130082264A1 (en) * 2011-09-30 2013-04-04 General Electric Company Photodetector having improved quantum efficiency
US20140284605A1 (en) * 2013-03-19 2014-09-25 National Chiao Tung University Tft-pin array substrate and assembly structure for flat-panel x-ray detector
US20150137088A1 (en) * 2012-06-20 2015-05-21 Koninklijke Philips N.V. Radiation detector with an organic photodiode
US20160111473A1 (en) * 2014-10-17 2016-04-21 General Electric Company Organic photodiodes, organic x-ray detectors and x-ray systems
CN109585477A (en) * 2018-10-31 2019-04-05 奕瑞影像科技（太仓）有限公司 Flat-panel detector structure and preparation method thereof
US20190378880A1 (en) * 2017-01-15 2019-12-12 Signtle Inc. Photodetector array

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110095266A1 (en) * 2008-06-25 2011-04-28 Oliver Hayden Photodetector and method for the production thereof
US20130082264A1 (en) * 2011-09-30 2013-04-04 General Electric Company Photodetector having improved quantum efficiency
US20150137088A1 (en) * 2012-06-20 2015-05-21 Koninklijke Philips N.V. Radiation detector with an organic photodiode
US20140284605A1 (en) * 2013-03-19 2014-09-25 National Chiao Tung University Tft-pin array substrate and assembly structure for flat-panel x-ray detector
US20160111473A1 (en) * 2014-10-17 2016-04-21 General Electric Company Organic photodiodes, organic x-ray detectors and x-ray systems
US20190378880A1 (en) * 2017-01-15 2019-12-12 Signtle Inc. Photodetector array
CN109585477A (en) * 2018-10-31 2019-04-05 奕瑞影像科技（太仓）有限公司 Flat-panel detector structure and preparation method thereof

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112490334A (en) * 2020-11-06 2021-03-12 奕瑞影像科技（太仓）有限公司 Manufacturing method of X-ray flat panel detector and X-ray flat panel detector
CN112736201A (en) * 2020-12-30 2021-04-30 奕瑞影像科技（太仓）有限公司 Indirect flat panel detector and preparation method thereof
CN112802871A (en) * 2020-12-30 2021-05-14 奕瑞影像科技（太仓）有限公司 Organic photoelectric flat panel detector
CN112736201B (en) * 2020-12-30 2025-01-21 奕瑞影像科技（太仓）有限公司 Indirect flat panel detector and preparation method thereof

Similar Documents

Publication Publication Date Title
Liu et al. All-inorganic lead-free NiO x/Cs3Bi2Br9 perovskite heterojunction photodetectors for ultraviolet multispectral imaging
CN108369282B (en) Detector element for detecting incident X-rays
US20170025622A1 (en) Ultrasensitive solution-processed perovskite hybrid photodetectors
KR20090013090A (en) Thin film element, manufacturing method thereof, semiconductor device
Kim et al. Top illuminated organic photodetectors with dielectric/metal/dielectric transparent anode
CN111312902A (en) Flat panel detector structure and preparation method thereof
US20130248822A1 (en) Broadband Polymer Photodetectors Using Zinc Oxide Nanowire as an Electron-Transporting Layer
Nguyen et al. Visible photodetector based on transition metal-doped ZnO NRs/PEDOT: PSS hybrid materials
CN112928137B (en) Organic photoelectric flat panel detector
JP6980662B2 (en) Organic optoelectronic devices, arrays of such devices, and methods for manufacturing such arrays.
KR20110015999A (en) Solar cell and manufacturing method thereof
Zou et al. Pixellated perovskite photodiode on IGZO thin film transistor backplane for low dose indirect X-ray detection
CN108336231A (en) A kind of organic photodetector of wide spectrum response
CN108807683B (en) Wide-spectral-response multiplication type organic photoelectric detector
WO2009022853A2 (en) Thin film type solar cell and method for manufacturing the same
KR20170029363A (en) Organic Device for Detecting Radiation and Thereof Manufacture Method
KR101206758B1 (en) Hybrid tandem type thin film Solar Cell and method of manufacturing the same
CN115020590A (en) Perovskite photoelectric detector, perovskite photoelectric detector array and preparation method thereof
CN112736201B (en) Indirect flat panel detector and preparation method thereof
CN111739963A (en) A kind of preparation method of silicon-based wide-spectrum photodetector
Dwivedi et al. PEDOT: PSS/Yb-doped ZnO heterojunction based flexible UV photodetector
CN116156904A (en) Dual-mode organic photodiode based on barrier layer interface regulation and control and preparation method thereof
CN108231944A (en) A kind of photodetector based on novel electron transport layer and preparation method thereof
CN112802871B (en) Organic photoelectric flat panel detector
Yan et al. Enhanced back-illuminated Ga2O3-based solar-blind ultraviolet photodetectors

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication
RJ01 Rejection of invention patent application after publication

Application publication date: 20200619