TW202018386A - Quantum dot display panel - Google Patents

Abstract

A quantum dot display panel includes a control substrate, a plurality of hole-carrier layers, a plurality of Quantum Dot Emmiting Layers (QD EMLs), a plurality of Electron Transport Layers (ETLs), a cathode, and a fluorinated treatment material. The control substrate has a flat surface and a plurality of anodes formed on the flat surface. The hole-carrier layers cover the anodes respectively. The QD EMLs are formed on the hole-carrier layers respectively. The ETLs are formed on the QD EMLs respectively. Each QD EML is between the ETL and the hole-carrier layer, and each ETL is a metal oxide layer. The cathode covers the ETLs. The fluorinated treatment material covers the cathode, and the fluorinated treatment material contains semi-fluorinated polymer.

Description

Quantum dot display panel

The invention relates to a display panel, and in particular to a quantum dot display panel.

The current display technology has developed a quantum dot display panel, which has a wider color gamut than a general display (such as a traditional liquid crystal display), so the quantum dot display can provide vivid images with better color saturation (saturation) . In addition, some current quantum dot display panels are electroluminescence (EL) displays, and have an emitting layer (Emitting Layer, EML). When the quantum dot display panel is powered on and operating, electrons and holes will recombine in the light-emitting layer to generate photons, so that the light-emitting layer emits light, so that the quantum dot display displays images.

The present invention provides a quantum dot display panel that utilizes a fluorinated treatment material to enhance the efficiency of the quantum dot display panel.

The quantum dot display panel provided by the present invention includes a control substrate, a plurality of hole carrier layers, a plurality of quantum dot light-emitting layers, a plurality of electron transport layers, a cathode, and a fluorine-containing modified material. The control substrate has a plane and a plurality of anodes formed on this plane. These hole carrier layers cover the anodes, respectively. These quantum dot light-emitting layers are formed on these hole carrier layers, respectively. These electron transport layers are formed on these quantum dot light-emitting layers, respectively. Each quantum dot light-emitting layer is located between the electron transport layer and the hole carrier layer, and each electron transport layer is a metal oxide layer. The cathode covers these electron transport layers. The fluorine-containing modified material covers the cathode, and the fluorine-containing modified material contains semi-fluorinated polymer.

In at least one embodiment of the present invention, the fluorine-containing modified material contains 30% to 50% fluorine by weight (wt%).

其中R¹ 為半過氟烷基（semi-perfluoroalkyl），而R² 為氫(H)或叔丁氧羰基（tert-butoxycarbonyl）。In at least one embodiment of the present invention, the aforementioned semi-fluoropolymer includes the following chemical structure:

Wherein R ¹ is semi-perfluoroalkyl (semi-perfluoroalkyl), and R ² is hydrogen (H) or tert-butoxycarbonyl (tert-butoxycarbonyl).

In at least one embodiment of the present invention, each quantum dot light-emitting layer has a first central region and a first edge region surrounding the first central region. The height of the first central region relative to the plane of the control substrate is smaller than the height of the first edge region relative to this plane.

In at least one embodiment of the present invention, each electron transport layer has a second central region and a second edge region surrounding the second central region. The height of the second central zone relative to the plane is smaller than the height of the second edge zone relative to the plane.

In at least one embodiment of the present invention, the material of each electron transport layer is selected from the group consisting of zinc oxide (ZnO), indium tin oxide (ITO), and indium zinc oxide (IZO) Ethnic group.

In at least one embodiment of the present invention, each electron transport layer includes a plurality of metal oxide nanoparticles. These metal oxide nanoparticles are stacked on each other, and the particle size of each metal oxide nanoparticle is less than or equal to 10 nanometers.

In at least one embodiment of the present invention, the cathode is a metal layer, and the material of the cathode includes aluminum, magnesium, or silver.

In at least one embodiment of the present invention, the material of each quantum dot light-emitting layer is selected from the group consisting of perovskite, cadmium sulfide, cadmium selenide, cadmium telluride, and indium phosphide.

In at least one embodiment of the present invention, the quantum dot display panel further includes a mesh partition wall and a transparent substrate. The mesh partition wall is formed on the plane of the control substrate and has a plurality of grids, wherein the hole carrier layers, the quantum dot light-emitting layers, and the electron transport layers are located in the grids, respectively, and the cathode covers the mesh partitions wall. The transparent substrate is disposed on the fluorine-containing modified material, wherein the fluorine-containing modified material is located between the transparent substrate and the cathode.

The present invention uses a fluorine-containing modified material to improve the interface between the electron transport layer and the film layer adjacent to it (such as at least one of the quantum dot light-emitting layer and the cathode) to reduce trapped (trapped) Electrons, thereby improving the performance of quantum dot display panels.

In order to make the features and advantages of the present invention more obvious and understandable, the embodiments are specifically described below, and in conjunction with the accompanying drawings, detailed descriptions are as follows.

In the following text, the same element will be denoted by the same element symbol. Secondly, in order to clearly present the technical features of the case, the dimensions (eg length, width, thickness, and depth) of elements (eg, layers, films, substrates, regions, etc.) in the drawings will be enlarged in unequal proportions. Therefore, the description and explanation of the following embodiments are not limited to the sizes and shapes presented by the elements in the drawings, but should cover the sizes, shapes, and deviations of the two due to actual manufacturing processes and/or tolerances. For example, the flat surface shown in the drawings may have rough and/or non-linear characteristics, and the acute angle shown in the drawings may be round. Therefore, the elements presented in the drawings in this case are mainly for illustration, and are not intended to accurately depict the actual shape of the elements, nor are they intended to limit the scope of patent applications in this case.

Secondly, the words "about", "approximately", or "substantially" appearing in the content of this case not only cover the clearly stated values and range of values, but also include those with ordinary knowledge in the technical field to which the invention belongs. The allowable deviation range, which can be determined by the error generated during the measurement, and the error is caused by the limitation of both the measurement system or the process conditions, for example. In addition, "about" may be expressed within one or more standard deviations of the aforementioned values, for example, within ±30%, ±20%, ±10%, or ±5%. The words "about", "approximately" or "substantially" appearing in this text can choose acceptable deviation range or standard deviation according to optical properties, etching properties, mechanical properties or other properties, not just one Standard deviation to apply all the above optical properties, etching properties, mechanical properties and other properties.

FIG. 1A is a schematic cross-sectional view of a quantum dot display panel according to at least one embodiment of the present invention. Referring to FIG. 1A, the quantum dot display panel 100 includes a control substrate 110 and a plurality of hole carrier layers 120, wherein the hole carrier layers 120 are all formed on one side of the control substrate 110. In detail, the control substrate 110 has a plane 110s and a plurality of anodes 111 formed on the plane 110s. The hole carrier layers 120 respectively cover the anodes 111 and can contact the anodes 111, but it is not limited to at least one embodiment of the present invention. The anodes 111 may be arranged in an array, and may be a metal layer or a transparent conductive film (Transparent Conductive Film, TCF), where the anode 111 may be a combination of at least one of a metal layer and a transparent conductive film. For example, the anode 111 may be formed by stacking at least two film layers, where these film layers may all be metal layers or transparent conductive films, or these film layers may include a metal layer and a transparent conductive film. The anode 111 may be tranparent or opaque. The anode 111 may be formed using physical vapor deposition (PVD), such as sputtering or evaporation.

The material of the transparent conductive film may be a transparent metal oxide (Transparent Conductive Oxide, TCO), such as zinc oxide (ZnO), indium tin oxide (ITO) or indium zinc oxide (IZO), or these transparent metal oxides Any combination. For example, the anode 111 may be a zinc oxide layer or an indium tin oxide layer, or a film layer formed by mixing zinc oxide and indium zinc oxide. Of course, the anode 111 may also be formed of other transparent conductive materials, so the material constituting the anode 111 is not limited to at least one of zinc oxide, indium tin oxide, and indium zinc oxide.

The control substrate 110 is, for example, a component array substrate, and has a plurality of control elements (not shown), where the control elements may be diodes or transistors, such as thin film transistors (Thin Film Transistor, TFT). Therefore, the control substrate 110 may be an active element array substrate (the control element is, for example, a transistor) or a passive element array substrate (the control element is, for example, a diode).

The structure of the control substrate 110 may be substantially the same as the structure of the element array substrate of the liquid crystal display panel (Liquid Cryatal Display Panel, LCD Panel) and the organic light-emitting diode display panel (Organic Light-Emitting Diode Display Panel, OLED Display Panel) And, the manufacturing method of the control substrate 110 is also similar to the manufacturing method of the element array substrate of both the liquid crystal display panel and the organic light emitting diode display panel. Therefore, even if the control element is not shown in FIG. 1A, those with ordinary knowledge in the technical field to which the present invention belongs will know the structure and manufacturing method of the control substrate 110.

The quantum dot display panel 100 further includes a plurality of quantum dot light emitting layers 130 and a plurality of electron transport layers 140, wherein the quantum dot light emitting layers 130 are respectively formed on the hole carrier layers 120, and the plurality of electron transport layers 140 are respectively formed On these quantum dot light emitting layers 130. Therefore, each quantum dot light emitting layer 130 will be located between the electron transport layer 140 and the hole carrier layer 120, wherein each quantum dot light emitting layer 130 may contact the electron transport layer 140 and the hole carrier layer 120, but it is not limited to the present invention. One embodiment. The electron transport layer 140 is an inorganic material layer. For example, each electron transport layer 140 is a metal oxide layer, and its material may be a transparent metal oxide.

For example, the material of each electron transport layer 140 may be selected from the group consisting of zinc oxide, indium tin oxide, and indium zinc oxide. That is, the electron transport layer 140 may be a zinc oxide layer, an indium tin oxide layer, or an indium zinc oxide layer, or a mixture of at least two of zinc oxide, indium tin oxide, and indium zinc oxide. Of course, the electron transport layer 140 may also contain materials other than zinc oxide, indium tin oxide, and indium zinc oxide, so the material constituting the electron transport layer 140 is not limited to the above transparent metal oxide.

The quantum dot display panel 100 further includes a cathode 150, wherein the cathode 150 covers these electron transport layers 140. The cathode 150 may also contact these electron transport layers 140, as shown in FIG. 1A, but is not limited to at least one embodiment of the present invention. The material of the cathode 150 may include aluminum, magnesium, or silver, where magnesium and silver can be made into a thin metal layer that can transmit light, so that the cathode 150 becomes a translucent or transparent film layer. Alternatively, the cathode 150 may be an opaque thick metal layer made of aluminum. Alternatively, the cathode 150 may also be a transparent conductive electrode made of metal oxide. In other words, the cathode 150 may be transparent, translucent, or opaque. In addition, the cathode 150 may be formed using physical vapor deposition (eg, sputtering or evaporation).

The main carriers of the electron transport layer 140 are electrons, and the main carriers of the hole carrier layer 120 are holes. The cathode 150 and the anode 111 can receive electrical energy input from an external power source, so that the electron transport layer 140 can inject electrons into the quantum dot light emitting layer 130, and the hole carrier layer 120 can inject holes into the quantum dot light emitting layer 130. In this way, electrons and holes can be recombined in the quantum dot light emitting layer 130 to generate photons, so that the quantum dot display panel 100 emits light, so that an image can be displayed.

Since the cathode 150 can be transparent, translucent, or opaque, the light emitted by the quantum dot light emitting layer 130 can be emitted from at least one of the cathode 150 and the anode 111. When the cathode 150 is transparent or translucent, the light of the quantum dot light emitting layer 130 can be transmitted along the direction U1, so that the image can be displayed on the first side 101 of the quantum dot display panel 100. When the cathode 150 is opaque, the light of the quantum dot light emitting layer 130 can be transmitted along the direction D1, so that the image can be displayed on the second side 102 of the quantum dot display panel 100, wherein the first side 101 is opposite to the second side 102 . In addition, when the cathode 150 is transparent or translucent, multiple light rays of the quantum dot light emitting layer 130 can be transmitted along the direction U1 and the direction D1, so that the image can be displayed on the first side 101 and the second side of the quantum dot display panel 100 at the same time The side 102, that is, the quantum dot display panel 100 can be made as a transparent display.

Each quantum dot light-emitting layer 130 contains a plurality of quantum dots and is an inorganic material layer. The material of each quantum dot light emitting layer 130 may be selected from the group consisting of perovskite, cadmium sulfide, cadmium selenide, cadmium telluride, and indium phosphide. That is, the quantum dot material in the quantum dot light emitting layer 130 may include at least one of perovskite, cadmium sulfide, cadmium selenide, cadmium telluride, and indium phosphide. In addition to the above materials, the quantum dot light emitting layer 130 may also include other materials, so the material of the quantum dot light emitting layer 130 is not limited to include any of perovskite, cadmium sulfide, cadmium selenide, cadmium telluride, and indium phosphide. One kind.

When the material of the quantum dot light emitting layer 130 is cadmium sulfide, cadmium selenide or cadmium telluride, indium phosphide, or any combination of these materials, the size of the quantum dots in the quantum dot light emitting layer 130 can be changed to obtain a predetermined energy gap, Therefore, the quantum dot light emitting layer 130 can emit light with a predetermined wavelength. When the material of the quantum dot light emitting layer 130 is perovskite, the quantum dots in the quantum dot light emitting layer 130 may have bonded halogen ions, and the energy gap of the quantum dot light emitting layer 130 may be different kinds of halogen ions. It is determined so that the quantum dot light emitting layer 130 can emit light of a predetermined wavelength. For example, perovskite with chloride ion (CsPbCl ₃ ) can emit blue light, perovskite with bromide ion (CsPbBr ₃ ) can emit green light, and perovskite with iodine ion (CsPbI ₃ ) can emit red light Light.

The quantum dot display panel 100 further includes a fluorine-containing modified material 160, which covers the cathode 150. The fluorine-containing modified material 160 shown in FIG. 1A can fully cover the cathode 150 and can contact the cathode 150, but is not limited to at least one embodiment of the present invention. The fluorine-containing modified material 160 may be a photoresist material, which basically does not damage the film layer of the organic light emitting diode (OLED). The fluorine-containing modified material 160 contains a semi-fluoro polymer, wherein the semi-fluoro polymer refers to a polymer in which part of hydrogen atoms are replaced by fluorine atoms. If all hydrogen atoms in the polymer are replaced by fluorine atoms, the polymer is a perfluorinated polymer.

Generally speaking, the semi-fluoropolymer may have a carbon-hydrogen bond and a carbon-fluorine bond. However, perfluoropolymers may have carbon-fluorine bonds, but generally do not have carbon-hydrogen bonds. Therefore, the chemical bond between the semi-fluoropolymer and the perfluoropolymer should be different, so the Raman spectrum of the semi-fluoropolymer and the perfluoropolymer with the same chemical main structure will be Present different results to each other. In other words, Raman spectroscopy can be used to distinguish between semi-fluoropolymers and perfluoropolymers under the same chemical main structure.

化學式（一）In this embodiment, the above semi-fluoropolymer may include the chemical structure shown in the following chemical formula (1). In the chemical formula (1), R ¹ is a semi-perfluoroalkyl group, such as (CH2)n(CF2) _m CF ₃ , where the number of carbon (C) can be 1 to 12, and n and m are positive integers. R ² is hydrogen (H), tert-butoxycarbonyl (tert-butoxycarbonyl) or tert-butyl methacrylate (tert-butyl methacrylate).

Chemical formula (1)

化學式（二）

化學式（三）

化學式（四）Further, the polymer may also comprise a semi-fluoro copolymer (Copolymer), which has the following chemical formula (II) main chemical structure wherein R ³ may be a hydroxyl (OH ^-) or the formula (III) or formula (IV ) Chemical structure.

Chemical formula (2)

Chemical formula (3)

Chemical formula (4)

表格（一）In this embodiment, the performance of the quantum dot display panel 100 can be changed as the weight percentage concentration of fluorine in the fluorine-containing modified material 160 changes, as shown in the following table (1).

Form (1)

Samples A, B, and C respectively represent three different blue pixels of the quantum dot display panel 100, and in samples A, B, and C, the material of the electron transport layer 140 of the three is zinc oxide, and The three fluorine-containing modified materials 160 contain different weight percent concentrations of fluorine, where sample A contains about 37% by weight of fluorine, sample B contains less than 30% by weight of fluorine, and sample C contains weight Fluorine with a percentage concentration greater than 50%. Therefore, the weight percentage of fluorine in sample C is the highest, while the weight percentage of fluorine in sample B is the lowest. The weight percent concentration of fluorine in sample A is between samples B and C.

In addition, in the table (1), the "starting voltage" refers to the values input to samples A, B, and C when the brightness of samples A, B, and C reaches 1000 candela per square meter (cd/m ² ). Voltage value, where candela per square meter can also be called nit. "CIE1931 chromaticity diagram x" and "CIE1931 chromaticity diagram y" represent the coordinate X and Y values in the CIE1931 chromaticity diagram, respectively, and represent the color of the light emitted by samples A, B, and C (which is blue) Coordinates on the CIE1931 chromaticity diagram. The unit cd/A shown in "current efficiency (LE)" means "candela/ampere", and "current efficiency/y value (LE/y)" means "current efficiency (LE)" and "CIE1931 chromaticity diagram The ratio between "y".

From Table (1), the peak wavelengths of samples A, B, and C are very similar to (Full Width at Half Maximum, FWHM), and the difference is very small. This means that the fluorine weight percent concentration of the fluorine-modified material 160 does not substantially affect the wavelength of the light emitted by the quantum dot display panel 100, that is, the fluorine weight percent concentration does not substantially affect the electrons and holes. Recombination. Secondly, among samples A, B and C, sample A has the lowest initial voltage and the largest current efficiency, current efficiency/y value and external quantum efficiency. It can be seen that the efficiency of sample A is better than that of samples B and C.

It can be seen that the greater the weight percentage of fluorine contained in the fluorine-modified material 160 (such as sample C) or less (such as sample B), the quantum dot display panel 100 cannot be optimized, and In this embodiment, the fluorine-containing modified material 160 may contain 30% to 50% fluorine by weight, for example, about 37% fluorine by weight, so that the quantum dot display panel 100 is at a starting voltage and current The efficiency, current efficiency/y value and external quantum efficiency have good performance. However, it must be noted that the fluorine-containing modified material 160 may also contain fluorine outside the above weight percent concentration range, so the fluorine in the fluorine-containing modified material 160 is not limited to be within the above weight percent concentration range .

The quantum dot display panel 100 may further include a mesh partition wall 180. The mesh partition wall 180 is formed on the plane 110s of the control substrate 110, and has a plurality of grids 181, wherein the meshes 181 extend from one side (eg, upper side) of the mesh partition wall 180 to the opposite side (eg, lower side) ), so the grid 181 is a through hole. The grids 181 are aligned to the anodes 111 respectively, so the grids 181 can be arranged in an array. The hole carrier layers 120, the quantum dot light-emitting layers 130, and the electron transport layers 140 are located in the grids 181, respectively, and are stacked in the grids 181.

Since each grid 181 is a through hole and is aligned with the anode 111, the mesh partition wall 180 does not completely cover the anode 111. Taking FIG. 1A as an example, the mesh partition 180 only covers the edge area of the anode 111, but does not cover the central area of the anode 111. In addition, these grids 181 can define sub-pixels of the quantum dot display panel 100, such as red pixels, green pixels, and blue pixels, and the cathode 150 covers the mesh partition 180 more comprehensively .

The quantum dot display panel 100 may further include a transparent substrate 170, which may be a sapphire substrate, a glass plate, or a transparent plastic plate, where the transparent plastic plate is made of, for example, poly (methyl methacrylate) (PMMA, PMMA) Force). The transparent substrate 170 is disposed on the fluorine-containing modified material 160, and the fluorine-containing modified material 160 is located between the transparent substrate 170 and the cathode 150, wherein the fluorine-containing modified material 160 fills the space between the transparent substrate 170 and the cathode 150 . In addition, the quantum dot display panel 100 may further include a dam 190 connected between the transparent substrate 170 and the control substrate 110, wherein the dam 190 may be located in an edge area of the control substrate 110 and surround the mesh partition 180 .

FIG. 1B is an enlarged schematic diagram of the quantum dot display panel in FIG. 1A. Referring to FIGS. 1A and 1B, the hole carrier layer 120, the quantum dot light emitting layer 130, and the electron transport layer 140 can all be formed by a soluble process. That is, the hole carrier layer 120, the quantum dot light emitting layer 130, and the electron transport layer 140 can be formed with a liquid solution. For example, after the mesh partition wall 180 is formed, various liquid solutions can be sprayed or dropped into these grids 181 in sequence to form the hole carrier layer 120, the quantum dot light emitting layer 130, and the electron transport layer 140 in sequence . Since the cohesion of these liquid solutions is less than the adhesion between these liquid solutions and the mesh partition wall 180, the film layer formed by the solution process will have a characteristic that the central area is recessed compared to the surrounding area.

Specifically, in the same hole carrier layer 120, the height H21 of the center of the hole carrier layer 120 relative to the plane 110s of the control substrate 110 is smaller than the height H22 of the edge of the hole carrier layer 120 relative to the plane 110s, as shown in FIG. 1B. Similarly, the quantum dot light emitting layer 130 and the electron transport layer 140 also have the characteristic that the center is lower than the surroundings. Each quantum dot light-emitting layer 130 has a first central region 131 and a first edge region 132 surrounding the first central region 131, wherein the height H31 of the first central region 131 relative to the plane 110s is smaller than the first edge region 132 relative to the plane 110s Height H32. Each electron transport layer 140 has a second central region 141 and a second edge region 142 surrounding the second central region 141, wherein the height H41 of the second central region 141 relative to the plane 110s is smaller than the height of the second edge region 142 relative to the plane 110s H42.

In particular, the mesh partition wall 180 can be formed of a photoresist material, so the mesh partition wall 180 can be subjected to photoresist after exposure and development, in which the mesh 181 is formed after exposure and development, and each mesh The width of the grid 181 is not uniform. Taking FIG. 1B as an example, the minimum width W1 of the grid 181 is located near the bottom of the anode 111, and the maximum width W2 of the grid 181 is located at the cathode 150, where the grid 181 gradually narrows from the cathode 150 toward the anode 111. Therefore, from the perspective of FIG. 1B, the mesh 181 has a structure with a lower width and a lower width.

In addition, each electron transport layer 140 may include a plurality of metal oxide nanoparticles 143, wherein the metal oxide nanoparticles 143 are stacked on each other. The particle size of each metal oxide nanoparticle 143 is less than or equal to 10 nanometers, for example, 5 nanometers, so these metal oxide nanoparticles 143 have a quantum confinement effect. Therefore, the metal oxide nanoparticles 143 have characteristics significantly different from the general metal oxide thin film. For example, when the material of the electron transport layer 140 is zinc oxide, the electron transport layer 140 may be formed of a plurality of zinc oxide nanoparticles stacked on top of each other, so the electron transport layer 140 and the general physical vapor deposition or chemical vapor deposition (Chemical The physical and chemical characteristics of the zinc oxide film formed by Vapor Deposition (CVD) are obviously different. In other words, even if the materials are the same, the electron transport layer 140 formed by the plurality of metal oxide nanoparticles 143 is not substantially equivalent to the metal oxide thin film formed by general physical vapor deposition or chemical vapor deposition.

In this embodiment, the hole carrier layer 120 may include an organic material layer, and may be a multilayer film, that is, the hole carrier layer 120 may include multiple film layers stacked on top of each other. Taking FIG. 1B as an example, each hole carrier layer 120 includes a first hole transmission layer 121, a second hole transmission layer 122, and a hole injection layer 123, and in the same layer of hole carrier layer 120, the first hole The transmission layer 121, the second hole transmission layer 122 and the hole injection layer 123 are stacked on top of each other, wherein the first hole transmission layer 121, the second hole transmission layer 122 and the hole injection layer 123 can all be formed by a solution process. In addition, in the embodiment shown in FIG. 1B, the first hole transport layer 121 and the second hole transport layer 122 may both be organic material layers, so the hole carrier layer 120 may include at least two organic material layers, but In other embodiments, the hole carrier layer 120 may include three or more organic material layers. Therefore, the hole carrier layer 120 shown in FIG. 1B is for illustration only and is not intended to limit the number of organic material layers included in the hole carrier layer 120.

It is worth mentioning that the fluorine-containing modified material 160 can generate a positive aging effect (positvie aging), so that the fluorine-containing modified material 160 can enhance the quantum without substantially changing the emission wavelength of the quantum dot display panel 100 The performance of the dot display panel 100, such as improving the brightness, current density, and current efficiency, as shown in FIGS. 2A to 2D, wherein FIGS. 2A to 2D are all quantum dots made with the same material composition and the same manufacturing method The display panel 100 performs measurement.

2A is a schematic diagram of the relationship between the voltage and current density of the quantum dot display panel and the control quantum dot display panel in FIG. 1A. Please refer to FIGS. 1B and 2A. In FIG. 2A, curve A10 represents the quantum dot display panel 100, and curve A11 represents the control quantum dot display panel, where the difference between the quantum dot display panel 100 and the control quantum dot display panel It is only the presence or absence of fluorine-containing modified material 160. In other words, the curve A10 represents the quantum dot display panel 100 including the fluorine-containing modified material 160, and the curve A11 represents the quantum dot display panel 100 that does not include the fluorine-containing modified material 160.

From FIG. 2A, under the condition of inputting the same voltage, the quantum dot display panel 100 can achieve a larger current density, while the control quantum dot display panel achieves a smaller current density. In other words, under the condition that the same current density is reached, the voltage required by the quantum dot display panel 100 will be lower than the voltage required by the control quantum dot display panel. Taking FIG. 2A as an example, the quantum dot display panel 100 (curve A10) requires a voltage of about 5.8 volts under the condition that the current density is also 10 milliamperes per square centimeter (mA/cm ² ), but in contrast to the quantum dot display panel ( Curve A11) requires 7.3 volts.

It can be seen that the quantum dot display panel 100 including the fluorine-containing modified material 160 obviously has better current density characteristics, that is, the fluorine-containing modified material 160 can improve the current density. In addition, the curve A10 shown in FIG. 2A is measured at least 3 minutes after the fluorine-containing modified material 160 is completed. That is to say, after forming the fluorine-containing modified material 160, there is no need to wait for a long time (for example, 1 hour, or even more than 1 day), the quantum dot display panel 100 has a good performance in terms of current density.

FIG. 2B is a schematic diagram of the relationship between the voltage and brightness of the quantum dot display panel and the control quantum dot display panel in FIG. 1A. Please refer to FIGS. 1B and 2B. Curves B10 and B11 shown in FIG. 2B respectively represent the quantum dot display panel 100 and the control quantum dot display panel. The quantum dot display panel 100 represented by the curve B10 includes a fluorine-containing modified material 160. And the curve B10 is also measured after at least 3 minutes after the fluorine-containing modified material 160 is completed. The control quantum dot display panel represented by the curve B11 does not include the fluorine-containing modified material 160, and the control quantum dot display panels measured in FIGS. 2A and 2B use the same material composition and the same manufacturing method. From FIG. 2B, under the condition of inputting the same voltage, the quantum dot display panel 100 can achieve higher brightness, while the control quantum dot display panel achieves lower brightness. Therefore, the fluorine-containing modified material 160 can improve the brightness of the quantum dot display panel 100 in a short time (at least 3 minutes), thereby improving the luminous efficacy of the quantum dot display panel 100.

2C is a schematic diagram of the relationship between the current density and current efficiency of the quantum dot display panel and the control quantum dot display panel in FIG. 1A, wherein the curves C10 and C11 shown in FIG. 2C represent the quantum dot display panel 100 and the control, respectively. Quantum dot display panel. 2A, the quantum dot display panel 100 represented by the curve C10 includes the fluorine-containing modified material 160, while the control quantum dot display panel represented by the curve C11 does not include the fluorine-containing modified material 160. In addition, the curve C10 shown in FIG. 2C is also measured after at least 3 minutes after the fluorine-containing modified material 160 is completed, and the control quantum dot display panels shown in FIGS. 2A and 2C also use the same material composition and the same Manufacturing method.

From FIG. 2C, under the same current density, the quantum dot display panel 100 has higher current efficiency than the control quantum dot display panel. Taking FIG. 2C as an example, the maximum current efficiency of the quantum dot display panel 100 (curve C10) is 2.21cd/A, while the maximum current efficiency of the control quantum dot display panel (curve C11) is 1.62cd/A. It can be seen that the fluorine-containing modified material 160 can also improve the current efficiency of the quantum dot display panel 100 in a short time (at least 3 minutes).

2D is a schematic diagram of the spectrum of both the quantum dot display panel and the control quantum dot display panel in FIG. 1A. Please refer to FIGS. 1B and 2D. The spectra D10 and D11 shown in FIG. 2D respectively represent the quantum dot display panel 100 and the comparative quantum dot display panel. The material composition and manufacturing method used in the comparative quantum dot display panel shown in FIG. 2D Both are the same as the control quantum dot display panel shown in FIG. 2A. In addition, the spectrum D10 is also measured after at least 3 minutes after the fluorine-containing modified material 160 is completed.

From FIG. 2D, the spectra D10 and D11 of the quantum dot display panel 100 and the control quantum dot display panel are similar. Even if the spectrum at the peak is enlarged into the spectrum D30, it can still be found that the difference between the spectra D10 and D11 is very small. This means that the fluorine-containing modified material 160 does not substantially affect the recombination between electrons and holes. Therefore, the wavelength of the light emitted by the quantum dot display panel 100 is substantially unaffected by the fluorine-containing modified material 160. In addition, in particular, the quantum dot display panel 100 represented by the curves A10, B10, C10 and the spectrum D10 in FIGS. 2A to 2D above, the fluorine-containing modified material 160 contains a concentration of about 37% by weight Fluorine, as in sample A in table (1).

3A is a schematic diagram of transient electrical excitation light analysis of the quantum dot display panel in FIG. 1A, and FIG. 3B is a schematic diagram of transient electrical excitation light analysis of the quantum dot display panel. Please refer to FIGS. 3A and 3B. The transient electrical excitation light analysis of FIG. 3A is for a quantum dot display panel 100 including a fluorine-containing modified material 160, wherein the fluorine-containing modified material 160 may contain about 37% by weight. 3A is measured after at least 3 minutes after the fluorine-containing modified material 160 is completed. The transient electrical excitation light analysis of FIG. 3B is for a quantum dot display panel 100 that does not include the fluorine-containing modified material 160, and both the quantum dot display panel 100 shown in FIG. 3A and the control quantum dot display panel shown in FIG. 3B The difference is only the presence or absence of fluorine-containing modified material 160. In addition, the material composition and manufacturing method of the quantum dot display panel 100 shown in FIG. 3A are the same as those of the quantum dot display panel 100 shown in FIG. 2A.

In FIG. 3A, curves V070, V075, and V080 respectively represent different voltages input to enable the quantum dot display panel 100 to emit light, where curve V070 means inputting 7 volts to the quantum dot display panel 100, and curve V075 means input 7.5 volts The voltage is to the quantum dot display panel 100, and the curve V080 means to input a voltage of 8 volts to the quantum dot display panel 100. Similarly, in FIG. 3B, curve V170 means inputting 7 volts to the control quantum dot display panel, curve V175 means inputting 7.5 volts to the control quantum dot display panel, and curve V180 means inputting 8 volts to the control quantum dot. Click the display panel.

Comparing FIG. 3A and FIG. 3B, under the condition of the same input voltage, whether the input voltage is 7 volts, 7.5 volts, or 8 volts, the time from the beginning of the quantum dot display panel 100 to the emission of saturated intensity light is significantly less than that of the control quantum dots The time from the start of the display panel to the emission of saturated intensity light, where the saturation intensity refers to the maximum intensity light, that is, the saturation intensity refers to the normalized intensity equal to 1 in FIGS. 3A and 3B. Taking FIG. 3A as an example, when the quantum dot display panel 100 is activated with a voltage of 7 to 8 volts, the intensity of the light emitted by the quantum dot display panel 100 within 5 microseconds after activation may be greater than 50% of the saturation intensity, of which 50 The saturation intensity of% refers to the normalized light intensity equal to 0.5 in FIG. 3A.

In contrast, in FIG. 3B, when the control quantum dot display panel is activated with a voltage of 7 to 8 volts, the intensity of the light emitted by the control quantum dot display panel within 5 microseconds after activation is still less than 50% of the saturation intensity. That is, compared to the control quantum dot display panel that does not include the fluorine-containing modified material 160, the quantum dot display panel 100 that includes the fluorine-containing modified material 160 can emit light of saturated intensity more quickly. It can be seen from this that the fluorine-containing modified material 160 can indeed shorten the time for the quantum dot display panel 100 to emit light of saturation intensity, so as to accelerate the light of the quantum dot display panel 100 to reach saturation intensity.

According to the above FIG. 2A to FIG. 2D, FIG. 3A and FIG. 3B, the fluorine-containing modified material 160 can indeed improve the current density, luminous power and current efficiency without substantially changing the spectrum of the quantum dot display panel 100, and can shorten The time to reach saturation intensity. Therefore, it is reasonable to speculate that the fluorine-containing modified material 160 has the effect of improving the interface of the electron carrier layer (ie, the cathode 150 and the electron transport layer 140). For example, ions or atoms diffused from the semi-fluoropolymer of the fluorine-modified material 160 can repair defects in at least one interface between the cathode 150 and the electron transport layer 140 and between the electron transport layer 140 and the quantum dot light emitting layer 130 (Defect) to reduce confined electronics. FIGS. 4A and 5A propose two types of multilayer film structures 400 and 500 to form the interface between the above two locations, respectively, to study the influence of the fluorine-containing modified material 160 on the above two interfaces.

4A is a schematic cross-sectional view of a multilayer film structure used to study the interface between a cathode and an electron transport layer, and FIG. 4B is a schematic diagram of an energy gap of the multilayer film structure in FIG. 4A. 4A and 4B, the multilayer film structure 400 is a pure electron carrier device (electron only device), that is, the main carriers in the multilayer film structure 400 are electrons. The multilayer film structure 400 includes a substrate 410, an electron transport layer 140, a cathode 150, and a fluorine-containing modified material 160. Similar to the quantum dot display panel 100 shown in FIG. 1B, in the multilayer film structure 400 shown in FIG. 4A, the electron transport layer 140, the cathode 150, and the fluorine-containing modified material 160 are also sequentially stacked on the substrate 410, and the electrons The transmission layer 140 is located between the substrate 410 and the cathode 150.

In the embodiment shown in FIG. 4A, the electron transport layer 140 is formed of a plurality of zinc oxide nanoparticles stacked on top of each other, and the cathode 150 is an aluminum metal layer, wherein the electron transport layer 140 (zinc oxide) has a higher Energy level, and the cathode 150 (aluminum) has a lower energy level, as shown in FIG. 4B. Since the multilayer film structure 400 is a pure electron carrier device, FIG. 4B only shows the energy gap of the electron transition in the upper half, and omitting the energy gap of the transition of the power hole in the lower half. The substrate 410 is a metal oxide substrate with a layer of metal oxide film, and the substrate 410 shown in FIG. 4A is an indium tin oxide substrate with a layer of indium tin oxide film (not shown), which can communicate with electrons Layer 140 is in contact. 4B, the energy level of the substrate 410 (that is, the energy level of indium tin oxide) is lower than that of the cathode 150. In addition, the energy level of indium tin oxide (substrate 410) is approximately -5.2 eV, and the energy level of the aluminum metal layer (cathode 150) is approximately -4.3 eV.

4C is a schematic diagram showing the relationship between the voltage and current density of the multilayer film structure of FIG. 4A and the comparative multilayer film structure. Please refer to FIGS. 4A and 4C, the curve 40c in FIG. 4C represents the multilayer film structure 400 in FIG. 4A, and the curve 41c represents the comparative multilayer film structure. The control multilayer film structure is similar to the multilayer film structure 400, but the only difference is the presence or absence of the fluorine-containing modified material 160, that is, the multilayer film structure 400 includes the fluorine-containing modified material 160, but the control multilayer film structure does not include the fluorine-containing modified material Material 160. From FIG. 4C, the changes between the voltage and current density of the control multilayer film structure and the multilayer film structure 400 are similar, that is, the performance of the two in terms of current density is not very different, so it is speculated that the fluorine-containing modified material 160 has no significant effect on the interface between the electron transport layer 140 and the cathode 150.

4D is a schematic diagram of the light excitation spectrum of both the multilayer film structure of FIG. 4A and the comparative multilayer film structure, wherein FIG. 4D is the multilayer laser film structure 400 of FIG. 4A irradiated with an ultraviolet laser beam and the aforementioned comparative multilayer film structure To achieve the phenomenon of light excitation light, the wavelength of the above-mentioned ultraviolet laser beam can be between 380 nm and 400 nm. Please refer to FIG. 4A and FIG. 4D, the spectrum 40d in FIG. 4D represents the multilayer film structure 400 in FIG. 4A, and the spectrum 41d represents the control multilayer film structure described above. From FIG. 4D, the spectrum 40d is similar to the spectrum 41d, and even most of the two sections overlap each other. This means that the fluorine-containing modified material 160 does not substantially affect the energy level of the interface between the cathode 150 and the electron transport layer 140.

FIG. 5A is a schematic cross-sectional view of a multilayer film structure used to study an interface between an electron transport layer and a quantum dot light-emitting layer, and FIG. 5B is a schematic diagram of an energy gap of the multilayer film structure in FIG. 5A. 5A and 5B, the multi-layer film structure 500 is also a pure electron carrier device, and includes a substrate 410, two electron transport layers 140, quantum dot light emitting layer 130, cathode 150 and fluorine-containing modified material 160, of which two layers The electron transport layer 140, the quantum dot light emitting layer 130, and the cathode 150 are all disposed on the substrate 410. The quantum dot light emitting layer 130 is formed between the two electron transport layers 140, one of the electron transport layers 140 is formed on the substrate 410, and the cathode 150 is formed on the other electron transport layer 140. In addition, except for the quantum dot light emitting layer 130, the multi-layer film structure 500 in FIG. 5A and the multi-layer film structure 400 in FIG. 4A are both made of the same material.

5C is a schematic diagram showing the relationship between the voltage and current density of the multilayer film structure of FIG. 5A and the comparative multilayer film structure. Please refer to FIG. 5A and FIG. 5C, the curve 50c in FIG. 5C represents the multilayer film structure 500 in FIG. 5A, and the curve 51c represents the comparative multilayer film structure, wherein the multilayer film structure 500 includes fluorine-containing modified material 160, and the comparative multilayer film The structure does not include the fluorine-containing modified material 160, that is, the difference between the multilayer film structure 500 and the control multilayer film structure is only the presence or absence of the fluorine-containing modified material 160.

From FIG. 5C, when the same voltage is input to the multilayer film structure 500 and the control multilayer film structure, the current density achieved by the multilayer film structure 500 is significantly greater than that achieved by the control multilayer film structure. It can be seen that the fluorine-containing modified material 160 can indeed improve the interface between the electron transport layer 140 and the quantum dot light-emitting layer 130. For example, the fluorine-containing modified material 160 may repair defects present at the interface between the electron transport layer 140 and the quantum dot light emitting layer 130 to reduce confined electrons, thereby increasing current density.

FIG. 5D is a schematic diagram of the light excitation spectrum of both the multilayer film structure of FIG. 5A and the comparative multilayer film structure, where FIG. 5D is the ultraviolet laser beam irradiating the multilayer film structure 500 of FIG. 5A with the aforementioned comparative multilayer film structure To achieve the photo-excitation light, the ultraviolet laser beam used in FIG. 5D is the same as the ultraviolet laser beam used in FIG. 4D. Please refer to FIG. 5A and FIG. 5D, the spectrum 50d in FIG. 5D represents the multilayer film structure 500 in FIG. 5A, and the spectrum 51d represents the control multilayer film structure described above. From FIG. 5D, the peak wavelength of the spectrum 50d and the peak wavelength of the spectrum 51d are substantially the same, and in the section other than the peak, the spectrum 50d and the spectrum 51d are quite similar, or even overlap. In other words, the fluorine-containing modified material 160 does not substantially affect the energy level of the interface between the electron transport layer 140 and the quantum dot light emitting layer 130.

However, the peak intensity of spectrum 50d is significantly higher than that of spectrum 51d. This means that in the multilayer film structure 500, the energy gap corresponding to the peak intensity can be excited by the ultraviolet laser beam to generate more photons. Compared with the control multilayer film structure, in the multilayer film structure 500, the interface between the electron transport layer 140 and the quantum dot light emitting layer 130 contains more unrestricted electrons, so the ultraviolet laser beam can excite more Electrons to generate more photons, thereby increasing the peak intensity of the spectrum 50d. It can be seen that the fluorine-modified material 160 can improve the interface between the electron transport layer 140 and the quantum dot light-emitting layer 130, for example, to repair defects in the above interface, so as to reduce the confined electrons, thereby improving current density and other performance.

According to the results shown in FIG. 4C, FIG. 4D, FIG. 5C, and FIG. 5D above, the fluorine-containing modified material 160 does improve the interface between the electron transport layer 140 and the quantum dot light emitting layer 130, but for the electron transport layer 140 and the cathode The interface between 150 has no significant effect. However, it must be emphasized that the results shown in FIGS. 4C, 4D, 5C and 5D are based on the premise that the electron transport layer 140 is formed of a plurality of zinc oxide nanoparticles stacked on top of each other and the cathode 150 is an aluminum metal layer under.

If other materials are used for both the electron transport layer 140 and the cathode 150, the fluorine-containing modified material 160 can also affect and improve the interface between the electron transport layer 140 and the cathode 150. Therefore, in the embodiments of FIGS. 4A to 5D, the fluorine-containing modified material 160 can improve the interface between the electron transport layer 140 and the quantum dot light-emitting layer 130, but in other embodiments, the fluorine-containing modified material 160 also The interface between the electron transport layer 140 and the cathode 150 can be improved, or both interfaces can be improved together. Therefore, the fluorine-containing modified material 160 is not limited to only improve the interface between the electron transport layer 140 and the quantum dot light emitting layer 130.

In summary, the use of the fluorine-containing modified material can produce a positive aging effect to improve the interface between the electron transport layer and the adjacent film layer, such as repairing the existing between the electron transport layer and the quantum dot light-emitting layer Interface defects to reduce trapped electrons. In this way, the above-mentioned fluorine-containing modified material can improve the performance of the quantum dot display panel.

Although the present invention has been disclosed as above with examples, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention belongs can make some modifications and retouching without departing from the spirit and scope of the present invention. The scope of protection of invention shall be subject to the scope defined in the appended patent application.

40c, 41c, 50c, 51c, A10, A11, B10, B11, C10, C11, V070, V075, V080, V170, V175, V180: curve 40d, 41d, 50d, 51d: spectrum 100: quantum dot display panel 101: First side 102: Second side 110: Control substrate 110s: Plane 111: Anode 120: Hole carrier layer 121: First hole transport layer 122: Second hole transport layer 123: Hole injection layer 130: Quantum dots Light emitting layer 131: first central region 132: first edge region 140: electron transport layer 141: second central region 142: second edge region 143: metal oxide nanoparticles 150: cathode 160: fluorine-containing modified material 170 : Transparent substrate 180: Mesh partition 181: Grid 190: Retaining wall 400, 500: Multi-layer film structure 410: Substrate D1, U1: Direction D10, D11: Spectrum D30: Spectrogram H21, H22, H31, H32, H41 , H42: height W1: minimum width W2: maximum width

FIG. 1A is a schematic cross-sectional view of a quantum dot display panel according to at least one embodiment of the present invention. FIG. 1B is an enlarged schematic diagram of the quantum dot display panel in FIG. 1A. FIG. 2A is a schematic diagram of the relationship between the voltage and current density of the quantum dot display panel and the control quantum dot display panel in FIG. 1A. FIG. 2B is a schematic diagram of the relationship between the voltage and the luminance of the quantum dot display panel and the control quantum dot display panel in FIG. 1A. FIG. 2C is a schematic diagram of the relationship between the current density and the current efficiency of the quantum dot display panel and the control quantum dot display panel in FIG. 1A. 2D is a schematic diagram of the spectrum of both the quantum dot display panel and the control quantum dot display panel in FIG. 1A. FIG. 3A is a schematic diagram of transient electroluminescence analysis (TrEL Analysis) of the quantum dot display panel in FIG. 1A. FIG. 3B is a schematic diagram of the transient electrical excitation light analysis of the display panel compared with the quantum dot. 4A is a schematic cross-sectional view of a multilayer film structure used to study the interface between a cathode and an electron transport layer. 4B is a schematic diagram of the energy gap of the multilayer film structure in FIG. 4A. 4C is a schematic diagram showing the relationship between the voltage and current density of the multilayer film structure of FIG. 4A and the comparative multilayer film structure. FIG. 4D is a schematic diagram of the photoluminescence (PL) spectrum of both the multilayer film structure of FIG. 4A and the control multilayer film structure. 5A is a schematic cross-sectional view of a multilayer film structure used to study the interface between an electron transport layer and a quantum dot light-emitting layer. 5B is a schematic diagram of the energy gap of the multilayer film structure in FIG. 5A. 5C is a schematic diagram showing the relationship between the voltage and current density of the multilayer film structure of FIG. 5A and the comparative multilayer film structure. FIG. 5D is a schematic diagram of the light excitation spectrum of both the multilayer film structure of FIG. 5A and the comparative multilayer film structure.

100: Quantum dot display panel

101: first side

102: second side

110: control board

110s: flat

111: anode

120: hole carrier layer

130: Quantum dot light emitting layer

140: electron transport layer

150: cathode

160: Fluorine modified materials

170: Transparent substrate

180: mesh partition

181: Grid

190: Retaining wall

D1, U1: direction

Claims (10)

A quantum dot display panel includes: a control substrate having a plane and a plurality of anodes formed on the plane; a plurality of hole carrier layers covering the anodes respectively; a plurality of quantum dot light-emitting layers formed on the planes On the hole carrier layer; a plurality of electron transport layers are formed on the quantum dot light-emitting layers, wherein each of the quantum dot light-emitting layers is located between the electron transport layer and the hole carrier layer, and each of the electron transport layers It is a metal oxide layer; a cathode covering the electron transport layers; and a fluorine-containing modified material covering the cathode, wherein the fluorine-containing modified material contains half of the fluoropolymer. The quantum dot display panel according to claim 1, wherein the fluorine-containing modified material contains 30% to 50% fluorine by weight.

The quantum dot display panel of claim 1, wherein the semi-fluoropolymer includes the following chemical structure: wherein R ¹ is a semi-perfluoroalkyl group, and R ² is hydrogen or t-butoxycarbonyl. The quantum dot display panel of claim 1, wherein each of the quantum dot light-emitting layers has a first central region and a first edge region surrounding the first central region, the first central region relative to the control substrate The height of the plane is smaller than the height of the first edge region relative to the plane. The quantum dot display panel of claim 4, wherein each of the electron transport layers has a second central region and a second edge region surrounding the second central region, the height of the second central region relative to the plane is less than The height of the second edge region relative to the plane. The quantum dot display panel of claim 1, wherein the material of each electron transport layer is selected from the group consisting of zinc oxide, indium tin oxide, and indium zinc oxide. The quantum dot display panel of claim 1, wherein each of the electron transport layers includes a plurality of metal oxide nanoparticles, the metal oxide nanoparticles are stacked on each other, and each of the metal oxide nanoparticle particles The diameter is less than or equal to 10 nm. The quantum dot display panel of claim 1, wherein the cathode is a metal layer, and the material of the cathode includes aluminum, magnesium, or silver. The quantum dot display panel according to claim 1, wherein the material of each quantum dot light emitting layer is selected from the group consisting of perovskite, cadmium sulfide, cadmium selenide, cadmium telluride, and indium phosphide. The quantum dot display panel according to claim 1, further comprising: a mesh partition wall formed on the plane of the control substrate and having a plurality of grids, wherein the hole carrier layers and the quantum dots The light-emitting layer and the electron transport layers are respectively located in the grids, and the cathode further covers the mesh partition wall; and a transparent substrate is disposed on the fluorine-containing modified material, wherein the fluorine-containing modified material is located Between the transparent substrate and the cathode.

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