CN112103406B - Quantum dot light-emitting device and preparation method thereof - Google Patents
Quantum dot light-emitting device and preparation method thereof Download PDFInfo
- Publication number
- CN112103406B CN112103406B CN202011130005.8A CN202011130005A CN112103406B CN 112103406 B CN112103406 B CN 112103406B CN 202011130005 A CN202011130005 A CN 202011130005A CN 112103406 B CN112103406 B CN 112103406B
- Authority
- CN
- China
- Prior art keywords
- quantum dot
- dot light
- polyether compound
- emitting device
- metal oxide
- 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.)
- Active
Links
Classifications
-
- 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
- H10K50/00—Organic light-emitting devices
- H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
- H10K50/14—Carrier transporting layers
- H10K50/16—Electron transporting layers
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K50/00—Organic light-emitting devices
- H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
- H10K50/11—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers
- H10K50/115—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers comprising active inorganic nanostructures, e.g. luminescent quantum dots
Abstract
The application relates to the field of quantum dot devices, in particular to a quantum dot light-emitting device and a preparation method thereof. A preparation method of a quantum dot light-emitting device mainly comprises the following steps: mixing polyether compounds and metal oxide nanoparticles to obtain a mixed solution, and forming a film on the quantum dot light-emitting layer by using the mixed solution; the polyether compound is an insulating compound. In the application, a film is formed on the quantum dot light-emitting layer, and the material of the film comprises polyether compound and metal oxide nano-particles, wherein the polyether compound is an insulating compound. The surface of the metal oxide nanoparticles has a plurality of functional groups, such as hydroxyl, carboxyl, amino, sulfydryl and the like. Hydrogen bonds are formed between the functional groups to prevent further electron transport. In addition, under the influence of external factors such as heat, electricity, light and the like, dehydration condensation between partial functional groups to form-O-bonds can occur to enhance the electron transport performance.
Description
Technical Field
The application relates to the field of quantum dot devices, in particular to a quantum dot light-emitting device and a preparation method thereof.
Background
The lifetime of a quantum dot light emitting device is related to a number of factors, such as stability issues of the light emitting material, conductivity issues of the charge transport layer of the device, device packaging issues, interface charge accumulation, etc.
At present, the hole transport rate is generally much lower than the electron transport rate, and too high electron transport rate may cause non-radiative recombination and form charge accumulation on one side of the device, resulting in deterioration of device performance and lifetime. The application aims to improve the service life of a quantum dot light-emitting device by improving the conductivity of a charge transport layer.
Disclosure of Invention
The embodiment of the application aims to provide a quantum dot light-emitting device and a preparation method thereof. Which aims to improve the lifetime of quantum dot light emitting devices.
The first aspect of the present application provides a method for manufacturing a quantum dot light emitting device, including:
mixing a polyether compound and metal oxide nanoparticles to obtain a mixed solution, and forming a film on the quantum dot light-emitting layer by using the mixed solution; the polyether compound is an insulating compound.
The polyether compound can increase the distance between metal oxide nano-particles, and can prevent dehydration condensation between functional groups on the surfaces of the metal oxide nano-particles to improve the transmission performance of electrons; the polyether compound can reduce the dehydration rate among functional groups, and meanwhile, oxygen atoms in the ether polymer can also form hydrogen bonds with hydroxyl (-OH) of the functional group on the surface of the metal oxide nano-particle, so that the electron mobility is integrally reduced due to the electron-withdrawing capacity of the hydrogen bonds; the mixed liquid is formed into a film to form an electron transmission layer which is arranged on the quantum dot light emitting layer to improve the transmission performance of electrons.
Accordingly, the improvement of the electron transport property is advantageous to the improvement of the lifetime of the quantum dot light emitting device.
In some embodiments of the first aspect of the present application, the polyether compound has a molecular weight of 1000 to 100000.
Optionally, the molecular weight of the polyether compound is 8000 to 30000.
In some embodiments of the first aspect of the present disclosure, the polyether compound has a functionality of 30 to 120.
In some embodiments of the first aspect of the present application, the polyether compound is selected from at least one of polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polybutylene glycol diglycidyl ether, polypentylene glycol diglycidyl ether, and polyhexamethylene glycol diglycidyl ether.
In some embodiments of the first aspect of the present disclosure, the concentration of the metal oxide nanoparticles in the mixed liquor is 16 to 51mg/ml.
In some embodiments of the first aspect of the present application, mixing the polyether compound with the metal oxide nanoparticles further comprises:
firstly, the polyether compound is mixed with a nonpolar solvent.
In some embodiments of the first aspect of the present application, the non-polar solvent comprises at least one of methanol, ethanol, acetonitrile, butanol, and isopropanol.
In some embodiments of the first aspect of the present application, the metal oxide nanoparticles comprise ZnO, niO, W 2 O 3 、Mo 2 O 3 、TiO 2 、SnO、ZrO 2 And Ta 2 O 3 At least one of (1).
In some embodiments of the first aspect of the present disclosure, the mixed solution is formed into a film at 30-50 ℃.
The second aspect of the present application provides a quantum dot light-emitting device, which is manufactured by the above method for manufacturing a quantum dot light-emitting device.
The embodiment of the application improves the electron transmission performance of the electron transmission layer of the quantum dot light-emitting device, so that the service life of the quantum dot light-emitting device is prolonged.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
The quantum dot light emitting device and the method of manufacturing the same according to the embodiments of the present application will be described in detail below.
A method for preparing a quantum dot light-emitting device mainly comprises the following steps:
mixing polyether compounds and metal oxide nanoparticles to obtain a mixed solution, and forming a film on the quantum dot light-emitting layer by using the mixed solution; the polyether compound is an insulating compound.
In the application, a film is formed on the quantum dot light-emitting layer, and the material of the film comprises polyether compound and metal oxide nano-particles, wherein the polyether compound is an insulating compound.
The surface of the metal oxide nanoparticles has a plurality of functional groups, such as hydroxyl, carboxyl, amino, sulfydryl and the like. Hydrogen bonds are formed between the functional groups to prevent further electron transport. In addition, under the influence of external factors such as heat, electricity, light and the like, dehydration condensation between partial functional groups to form-O-bonds can occur to enhance the electron transport performance. Meanwhile, oxygen atoms in the ether polymer and hydroxyl (-OH) which is a functional group on the surface of the metal oxide nano-particle form hydrogen bonds, and the electron mobility is integrally reduced due to the electron withdrawing capacity of the hydrogen bonds.
In the embodiment of the application, the polyether compound can increase the distance between the metal oxide nanoparticles, and prevent the formation of hydrogen bonds between functional groups on the surfaces of the metal oxide nanoparticles so as to improve the electron transport performance; the polyether compound can reduce the dehydration rate among functional groups and improve the transmission performance of electrons. Accordingly, the improvement of the electron transport property is advantageous for the improvement of the lifetime of the quantum dot light emitting device.
In the examples of the present application, the molecular weight of the polyether compound is 1000 to 100000. Illustratively, the polyether compound has a molecular weight of 1000 to 2000; or 2000-3500, 4500-6500, 7000-8000, 9000-15000, 15000-3000, 90000-100000, etc.
The polyether compound with a relatively high molecular weight is beneficial to blocking hydrogen bonds formed between functional groups on the surface of the metal oxide nanoparticles, but the polyether compound with a relatively high molecular weight can cause non-uniformity of a film obtained after film formation, so that, in some embodiments of the present application, the molecular weight of the polyether compound is 1000 to 100000.
Further, in some embodiments herein, the functionality of the polyether compound is from 30 to 120.
Illustratively, the polyether compound is at least one selected from the group consisting of polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, polypentylene glycol diglycidyl ether, and polyhexamethylene glycol diglycidyl ether.
In this embodiment, the polyether compound is polyethylene glycol diglycidyl ether.
The molecular structural formula of the polyethylene glycol diglycidyl ether is as follows:
in other embodiments of the present application, the polyether compound may be other polyethylene glycol diglycidyl ethers.
In embodiments of the present application, the metal oxide nanoparticles comprise ZnO, niO, W 2 O 3 、Mo 2 O 3 、TiO 2 、SnO、ZrO 2 And Ta 2 O 3 At least one of (1). For example, in the present embodiment, the metal oxide nanoparticles are ZnO or ZrO 2 。
In the examples of the present application, the concentration of the metal oxide nanoparticles in the mixed solution is 16 to 51mg/ml. In other words, the mixed solution contains 16 to 51mg of the metal oxide nanoparticles per 1ml of the mixed solution. For example, the concentration of the metal oxide nanoparticles in the mixed solution is 16mg/ml, 18mg/ml, 23mg/ml, 30mg/ml, 34mg/ml, 40mg/ml, 43mg/ml, 50mg/ml, 51mg/ml.
In some embodiments of the present application, the mixed solution further comprises a nonpolar solvent.
Further, the method for mixing the polyether compound with the metal oxide nanoparticles comprises the following steps: firstly, the polyether compound is mixed with a nonpolar solvent.
The polyether compound is mixed with the nonpolar solvent and then mixed with the metal oxide nanoparticles, so that the metal oxide nanoparticles and the polyether compound can be fully dispersed. The metal oxide nano-particles after being fully dispersed can reduce the number of hydrogen bonds formed by surface groups of the metal oxide nano-particles.
Illustratively, the nonpolar solvent may include at least one of methanol, ethanol, acetonitrile, butanol, and isopropanol.
The volume ratio of the nonpolar solvent to the polyether compound can be 1; for example, 1.
In other embodiments of the present application, the non-polar solvent may be other solvents, or in other embodiments, the non-polar solvent may not be included in the mixed solution.
In the embodiments of the present application, the film formation method may be spin coating or coating.
In this embodiment, a method for manufacturing a quantum dot light-emitting device includes:
mixing 3-10ml of polyethylene glycol diglycidyl ether with 10ml of ethanol, then adding 100mg of metal oxide nano-particles, and stirring for 20-40 minutes to uniformly disperse the metal oxide nano-particles in the solution to obtain a mixed solution.
And forming a film on the mixed solution on the quantum dot light-emitting layer by adopting a spin coating or coating mode, and baking the film at 30-60 ℃ until the film is dried.
The preparation method of the quantum dot light-emitting device provided by the embodiment of the application has the main advantages that:
the polyether compound increases the distance between metal oxide nano particles, and prevents hydrogen bonds formed between functional groups, thereby improving the transmission performance of electrons; the polyether compound can reduce the dehydration rate among functional groups and improve the transmission performance of electrons. Accordingly, the improvement of the electron transport property is advantageous to the improvement of the lifetime of the quantum dot light emitting device.
The embodiment of the application also provides a quantum dot light-emitting device which is mainly prepared by the preparation method of the quantum dot light-emitting device.
The electron transmission performance of the electron transmission layer of the quantum dot light-emitting device is improved, so that the service life of the quantum dot light-emitting device is prolonged.
The features and properties of the present application are described in further detail below with reference to examples.
Example 1
The embodiment provides a quantum dot light-emitting device which is mainly prepared by the following steps:
sequentially preparing a hole transport layer, a quantum dot light emitting layer, an electron transport layer and a cathode on a clean ITO glass substrate; the preparation steps of the electron transport layer are as follows:
3ml of polyethylene glycol diglycidyl ether is mixed with 10ml of ethanol, wherein the molecular weight of the polyethylene glycol diglycidyl ether is about 1000. Then 100mgZnO nanoparticles are added, and the mixture is stirred for 20 minutes to uniformly disperse the metal oxide nanoparticles in the solution to obtain a mixed solution. And forming a film on the quantum dot light-emitting layer by adopting a spin coating mode, and baking the film at 30 ℃ until the film is dried.
Example 2
The embodiment provides a quantum dot light-emitting device which is mainly prepared by the following steps:
sequentially preparing a hole transport layer, a quantum dot light emitting layer, an electron transport layer and a cathode on a clean ITO glass substrate; the preparation steps of the electron transport layer are as follows:
5ml of polyethylene glycol diglycidyl ether is mixed with 10ml of ethanol, wherein the molecular weight of the polyethylene glycol diglycidyl ether is about 10000. Then 100mgZnO nanoparticles are added, and stirring is carried out for 40 minutes to ensure that the metal oxide nanoparticles are uniformly dispersed in the solution to obtain a mixed solution. And forming a film on the quantum dot light-emitting layer by adopting a coating mode, and baking the film at 40 ℃ until the film is dried.
Example 3
The embodiment provides a quantum dot light-emitting device which is mainly prepared by the following steps:
sequentially preparing a hole transport layer, a quantum dot light emitting layer, an electron transport layer and a cathode on a clean ITO glass substrate; the preparation steps of the electron transport layer are as follows:
mixing 7ml of polyethylene glycol diglycidyl ether with 10ml of ethanol, wherein the molecular weight of the polyethylene glycol diglycidyl ether is about 10000. Then 100mg TiO was added 2 And stirring the nano particles for 50 minutes to uniformly disperse the metal oxide nano particles in the solution to obtain a mixed solution. And forming a film on the quantum dot light-emitting layer by adopting a coating mode, and baking the film at 50 ℃ until the film is dried.
Example 4
The embodiment provides a quantum dot light-emitting device which is mainly prepared by the following steps:
preparing a hole transport layer, a quantum dot light emitting layer, an electron transport layer and a cathode on a clean ITO glass substrate in sequence; the preparation steps of the electron transport layer are as follows:
mixing 7ml of polyethylene glycol diglycidyl ether with 10ml of ethanol, wherein the molecular weight of the polyethylene glycol diglycidyl ether is about 10000. Then 100mg TiO was added 2 Stirring the nanoparticles for 50 minutes to obtain metal oxide nanoparticlesThe particles are uniformly dispersed in the solution to obtain a mixed solution. And forming a film on the mixed solution on the quantum dot light-emitting layer by adopting a spin coating or coating mode, and baking the film at 70 ℃ until the film is dried.
Comparative example 1
The present comparative example provides a quantum dot light-emitting device, which is mainly produced by the steps of:
sequentially preparing a hole transport layer, a quantum dot light emitting layer, an electron transport layer and a cathode on a clean ITO glass substrate; the preparation steps of the electron transport layer are as follows:
taking 13ml of ethanol, adding 100mgZnO nanoparticles, and stirring for 20 minutes to uniformly disperse the metal oxide nanoparticles in the solution to obtain a mixed solution. And forming a film on the mixed solution on the quantum dot light-emitting layer by adopting a spin coating mode, and baking the film at 30 ℃ until the film is dried.
Test examples
The quantum dot light-emitting devices provided in examples 1 to 4 and comparative example 1 were tested for luminous efficiency and service life; the lifetime T95 means that the luminance of the device is 5000cd/m 2 Time at 95% decay at current density. The test results are shown in Table 1.
TABLE 1 test results of examples 1 to 4 and comparative example 1
| Examples | Luminous efficiency | Life T95 |
| Example 1 | 12 | 150 |
| Example 2 | 13 | 160 |
| Example 3 | 11 | 180 |
| Example 4 | 12.5 | 168 |
| Comparative example 1 | 10 | 100 |
As can be seen from table 1, the efficiency and the service life of the quantum dot light emitting devices provided in examples 1 to 4 of the present application are significantly higher than those of comparative example 1, and it can be seen that the electron transport layer obtained by the preparation method of the quantum dot light emitting device provided in the present application can improve the electron transport performance. Further improving the efficiency and the service life of the quantum dot light-emitting device.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. A method for manufacturing a quantum dot light-emitting device, comprising:
mixing a polyether compound and metal oxide nanoparticles to obtain a mixed solution, and forming a film on the quantum dot light-emitting layer by using the mixed solution; the polyether compound is an insulating compound;
the polyether compound is at least one selected from polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, polypentylene glycol diglycidyl ether and polyhexamethylene glycol diglycidyl ether.
2. The method of claim 1, wherein the polyether compound has a molecular weight of 1000 to 100000.
3. The method of claim 2, wherein the polyether compound has a molecular weight of 8000 to 30000.
4. The method of claim 2, wherein the polyether compound has a functionality of 30 to 120.
5. The method of claim 1, wherein the concentration of the metal oxide nanoparticles in the mixed solution is 16 to 51mg/ml.
6. The method for preparing a quantum dot light-emitting device according to any one of claims 1 to 5, wherein the step of mixing the polyether compound with the metal oxide nanoparticles further comprises:
firstly, the polyether compound is mixed with a nonpolar solvent.
7. The method of claim 6, wherein the non-polar solvent comprises at least one of methanol, ethanol, acetonitrile, butanol, and isopropanol.
8. The method of any one of claims 1 to 5, wherein the metal oxide nanoparticles comprise at least one of ZnO, niO, W2O3, mo2O3, tiO2, snO, zrO2, and Ta2O 3.
9. The method of manufacturing a quantum dot light-emitting device according to any one of claims 1 to 5, wherein the mixed solution is formed into a film at 30 to 50 ℃.
10. A quantum dot light-emitting device, characterized in that it is produced by the method of producing a quantum dot light-emitting device according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011130005.8A CN112103406B (en) | 2020-10-20 | 2020-10-20 | Quantum dot light-emitting device and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011130005.8A CN112103406B (en) | 2020-10-20 | 2020-10-20 | Quantum dot light-emitting device and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112103406A CN112103406A (en) | 2020-12-18 |
| CN112103406B true CN112103406B (en) | 2023-04-18 |
Family
ID=73784491
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011130005.8A Active CN112103406B (en) | 2020-10-20 | 2020-10-20 | Quantum dot light-emitting device and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112103406B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113838974A (en) * | 2021-09-24 | 2021-12-24 | 长江先进存储产业创新中心有限责任公司 | Phase change memory and preparation method thereof |
| CN117858531A (en) * | 2022-09-29 | 2024-04-09 | Tcl科技集团股份有限公司 | Composite material, photoelectric device and preparation method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110964371A (en) * | 2019-12-18 | 2020-04-07 | 苏州星烁纳米科技有限公司 | Ink composition and preparation method of quantum dot light-emitting diode |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104388089B (en) * | 2014-11-04 | 2017-06-06 | 深圳Tcl新技术有限公司 | A kind of preparation method of hydridization perovskite quanta point material |
| CN106601923A (en) * | 2016-12-19 | 2017-04-26 | 华南理工大学 | Full-color display component for organic and inorganic quantum dot hybridization and preparing method thereof |
| CN107359248B (en) * | 2017-07-03 | 2019-08-02 | 武汉理工大学 | A kind of stabilization is without efficient organic solar batteries device of light bath and preparation method thereof |
| CN108550697A (en) * | 2017-10-30 | 2018-09-18 | 上海幂方电子科技有限公司 | Flexible organic solar batteries and its all print preparation method |
| CN109935714B (en) * | 2017-12-15 | 2021-04-23 | Tcl科技集团股份有限公司 | Electron transport material, preparation method thereof and light emitting diode |
| CN111725440B (en) * | 2020-07-01 | 2022-12-09 | 合肥福纳科技有限公司 | Metal oxide nanoparticle, processing method thereof and QLED device |
-
2020
- 2020-10-20 CN CN202011130005.8A patent/CN112103406B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110964371A (en) * | 2019-12-18 | 2020-04-07 | 苏州星烁纳米科技有限公司 | Ink composition and preparation method of quantum dot light-emitting diode |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112103406A (en) | 2020-12-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112103406B (en) | Quantum dot light-emitting device and preparation method thereof | |
| TW595029B (en) | Electroluminescent arrangements | |
| KR101739517B1 (en) | Method for manufacturing thin film including nickel oxide nanoparticle and solar cell having the same | |
| TW200539195A (en) | Electrically conducting organic polymer/nanoparticle composites and methods for use thereof | |
| CN107603339A (en) | Quantum dot ink and electroluminescent device | |
| JP2007007648A (en) | Dispersant, paste composition including it and inorganic element manufactured using it, and display device including it | |
| CN111584731B (en) | Electron transport material, thin film, quantum dot light-emitting diode and preparation method thereof | |
| CN107474632A (en) | Inkjet printing perovskite ink and preparation method thereof | |
| KR20160026973A (en) | Nanoparticle-based ink formulations | |
| CN110957436B (en) | Solvent-resistant mixed type hole transport material composition and quantum dot light-emitting diode | |
| CN111725440A (en) | Metal oxide nanoparticle, processing method thereof and QLED device | |
| US20200325586A1 (en) | Electrode for Gas Generation, Method of Preparing the Electrode and Device Including the Electrode for Gas Generation | |
| WO2021248877A1 (en) | Composite material, preparation method therefor and light-emitting diode | |
| CN112103407B (en) | Preparation method of electron transport layer and quantum dot light-emitting device | |
| US11139433B2 (en) | Tungstate ion solution and hybrid photovoltaic device | |
| CN112103405B (en) | Preparation method of solid film, quantum dot light-emitting device and preparation method | |
| CN110729406A (en) | Mixed hole injection layer QLED device and preparation method thereof | |
| CN113054117B (en) | Light emitting diode and method for manufacturing the same | |
| US20240076197A1 (en) | Composite electron transport material and preparation method therefor, and light-emitting diode | |
| CN114039002B (en) | Electron transport ink, electron transport film, electroluminescent diode, and display device | |
| WO2021129710A1 (en) | Preparation method for quantum dot light emitting diode | |
| CN1149606C (en) | Application of electrically conductive polymers and their blend system in field-emission cathode | |
| CN113130826B (en) | Composition, preparation method thereof and light-emitting diode | |
| CN115491194B (en) | Precursor solution of zinc oxide, preparation method thereof and light-emitting device | |
| US11929249B2 (en) | Methods for forming a field emission cathode |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |