CN102201549B - Substrate for flexible light emitting device and fabrication method thereof - Google Patents

Abstract

The invention discloses a substrate for a flexible light-emitting device, which includes a flexible substrate and a conductive layer, and is characterized in that the flexible substrate and the conductive layer are composed of one of the following two methods: ①The flexible substrate is Transparent dielectric polymer material, the conductive layer is a silver nanowire film, and the gaps of the silver nanowire film are filled with inorganic light-emitting nanoparticles; ②The flexible substrate is a transparent medium doped with inorganic light-emitting nanoparticles An electrical polymer material, the conductive layer is a silver nanowire film, and the gaps of the silver nanowire film are filled with a transparent dielectric polymer material doped with inorganic light-emitting nanoparticles. The substrate solves the problems of large roughness of the silver nanowire film and poor bonding force between the silver nanowire film and the flexible substrate, improves the electrical conductivity and the flatness of the surface of the silver nanowire film, and increases the compatibility between the silver nanowire film and the flexible substrate. Bonding force between flexible substrates.

Description

A substrate for a flexible light-emitting device and its preparation method

technical field

The invention relates to the technical field of organic optoelectronics, in particular to a substrate for a flexible light-emitting device and a preparation method thereof.

Background technique

Optoelectronics technology is a rapidly developing industry with high technological content after microelectronics technology. With the rapid development of optoelectronic technology, optoelectronic products such as solar cells, optical image sensors, flat panel displays, and thin film transistors have gradually matured, and they have greatly improved people's lives. At the same time, the wide application of optoelectronic information technology in various fields of social life has also created a huge growing market. Developed countries regard the optoelectronic information industry as one of the key development areas, and the competition in the optoelectronic information field is unfolding worldwide.

At present, organic optoelectronic devices are mostly prepared on rigid substrates (such as glass or silicon wafers). Although they have excellent device performance, they are weak in anti-vibration and impact resistance, relatively heavy in weight, and inconvenient to carry. The application in some occasions is greatly restricted. Attempts have been made to deposit organic optoelectronic devices on flexible substrates instead of rigid substrates.

The benefits of using a flexible substrate instead of a rigid one are that the product is lighter, less breakable, takes up less space and is more portable. However, despite these advantages, there are still many limitations in replacing rigid substrates with flexible substrates, and the fabrication of flexible devices still has many fundamental issues to be solved. For flexible substrates, since the surface smoothness of flexible substrates is far less than that of rigid substrates, special equipment and difficult processes are required for surface smoothing of flexible substrates, which increases the production cost of substrates; flexible substrates The water and oxygen transmission rate of the substrate is much higher than that of the rigid substrate, which causes the optoelectronic device to be affected by the water and oxygen passing through the substrate, which reduces the performance of the device.

For the electrode layer, the conventional electrode layer material In ₂ O ₃ :SnO ₂ (ITO) used as the electrode of the flexible substrate has the following disadvantages: (1) Indium in ITO is highly toxic and harmful to the human body during preparation and application ; (2) In ₂ O ₃ in ITO is expensive and the cost is high; (3) ITO thin film is susceptible to the reduction effect of hydrogen plasma, and the efficacy is reduced, and this phenomenon will also occur at low temperature and low plasma density; (4) The ITO film on the flexible substrate will have a decrease in conductivity due to the bending of the flexible substrate; (5) the use of a thick ITO layer will reduce the light transmittance, and 50-80% of the light will be on the glass, ITO And the organic layer is absorbed, and it is difficult to adopt a thin ITO layer process. In recent years, due to the high electrical conductivity and visible light transmittance of silver nanowire film, it has become a potential electrode material that can replace ITO, but the silver nanowire film has large surface roughness and the gap between silver nanowire film and flexible substrate The disadvantage of poor inter-bonding force reduces the performance of optoelectronic devices based on silver nanowire thin film electrodes.

Therefore, if the above-mentioned problems can be solved, optoelectronic devices will be more widely used and developed more rapidly.

Contents of the invention

The problem to be solved by the present invention is: how to provide a substrate for a flexible light-emitting device and its preparation method, the substrate solves the problems of large roughness of the silver nanowire film and poor bonding force between the silver nanowire film and the flexible substrate, The flatness of the surface of the silver nanowire film and the binding force between the silver nanowire film and the flexible substrate are improved.

The technical problem proposed by the present invention is solved by providing a substrate for a flexible light-emitting device, including a flexible substrate and a conductive layer, characterized in that the flexible substrate and the conductive layer are formed in one of the following two ways: Composition: ① The flexible substrate is a transparent dielectric polymer material, the conductive layer is a silver nanowire film, and the gaps of the silver nanowire film are filled with inorganic light-emitting nanoparticles; ② The flexible substrate is A transparent dielectric polymer material doped with inorganic luminescent nanoparticles, the conductive layer is a silver nanowire film, and gaps in the silver nanowire film are filled with a transparent dielectric polymer material doped with inorganic luminescent nanoparticles .

According to the substrate for flexible light-emitting devices provided by the present invention, it is characterized in that the size of the inorganic luminescent nanoparticles is 1-100 nm, and in the second method, the doping mass ratio of the inorganic luminescent nanoparticles is less than or equal to 40%.

According to the substrate for flexible light-emitting devices provided by the present invention, it is characterized in that the inorganic light-emitting nanoparticles are made of sulfide, oxide, fluoride, phosphate, vanadate, niobate, aluminate or molybdic acid Salt, etc. are used as luminescent substrates, and luminescent particles with rare earth lanthanides as activators and co-activators.

According to the substrate for flexible light-emitting devices provided by the present invention, it is characterized in that the sulfide includes zinc sulfide, lanthanum sulfide, calcium sulfide, cerium sulfide, praseodymium sulfide, neodymium sulfide, samarium sulfide and gadolinium sulfide; the oxide includes Zinc oxide, yttrium oxide, titanium oxide, gadolinium oxide, and lutetium oxide; the fluorides include yttrium fluoride, gadolinium fluoride, lanthanum fluoride, and cerium fluoride; the phosphates include lanthanum phosphate, gadolinium phosphate, strontium phosphate, Yttrium phosphate and barium phosphate; Described vanadate comprises gadolinium vanadate, yttrium vanadate, lanthanum vanadate, cerium vanadate, calcium vanadate, lead vanadate and strontium vanadate; Described niobate comprises calcium niobate, Yttrium niobate, gadolinium niobate and lutetium niobate; said aluminates include yttrium aluminate, barium aluminate, gadolinium aluminate, calcium aluminate and strontium aluminate; said molybdates include lanthanum molybdate, molybdate strontium and barium molybdate; the rare earth lanthanides include europium, samarium, erbium, neodymium, terbium, dysprosium, samarium, cerium, ytterbium and praseodymium.

According to the substrate for flexible light-emitting devices provided by the present invention, it is characterized in that the transparent dielectric polymer material includes polyethylene, polymethyl methacrylate, polycarbonate, polyurethane, polyimide , PVC resin polyacrylic acid, polyaryletherketone, polyvinylidene fluoride, polyester, polyethylene naphthalate, polyacrylate, polyhexamethylene terephthalamide, polybutylene and polyvinyl alcohol.

A method for preparing a substrate for a flexible light-emitting device, comprising the following steps:

① Clean the rigid substrate (such as glass or silicon wafer) with surface roughness less than 1nm, and dry it with dry nitrogen after cleaning;

② Preparation of silver nanowire film on a clean substrate by spin coating or spray coating or self-assembly or inkjet printing or screen printing;

③ Spin-coat or spray-coat a transparent dielectric polymer material layer doped with inorganic luminescent nanoparticles on the silver nanowire film, or first spin-coat or drop-coat or spray-coat a solution containing inorganic luminescent nanoparticles, and then spin-coat or spray-coat a transparent Dielectric polymer material layer, the transparent dielectric polymer material includes polyethylene, polymethyl methacrylate, polycarbonate, polyurethane, polyimide, vinyl acetate polyacrylic acid, poly Aryl ether ketones, polyvinylidene fluoride, polyesters, polyethylene naphthalate, polyacrylates, polyhexamethylene terephthalamide, polybutylene, and polyvinyl alcohol;

④ heat curing treatment on the surface of the rigid substrate;

⑤Peel off the surface of the rigid substrate by peeling off the silver nanowire film and the cured transparent dielectric polymer material layer or the transparent dielectric polymer material layer doped with inorganic luminescent nanoparticles to form a flexible conductive substrate;

⑥ Test the parameters of the transmittance, conductivity and surface morphology of the flexible conductive substrate.

Beneficial effects of the present invention: there are inorganic light-emitting nanoparticles in the conductive layer of the present invention, so that the conductive layer emits light under excitation light irradiation, which not only enhances the luminous intensity of the light-emitting device based on the substrate, but also simplifies the light-emitting device based on the substrate structure and required materials, and at the same time, the silver nanowires used in the conductive layer can improve the luminous intensity of the inorganic luminescent nanoparticles, further increasing the luminous intensity of the light-emitting device based on the substrate; the conductive layer of the present invention has a small roughness Prepared on a rigid substrate, the voids of the conductive layer are filled with inorganic luminescent nanoparticles or transparent dielectric polymer materials doped with inorganic luminescent nanoparticles, and the conductive layer of the flexible substrate is formed by peeling off, which improves the smoothness of the surface of the conductive layer ; The transparent dielectric polymer material in the flexible substrate of the present invention has the characteristics of high visible light transmittance, which improves the visible light transmittance of the flexible substrate; the flexible substrate is formed by first preparing the conductive layer and then preparing the flexible substrate. The substrate increases the bonding force between the conductive layer and the flexible substrate.

Description of drawings

Fig. 1 is a schematic structural view of a substrate for a flexible light-emitting device according to Embodiment 1-10 of the present invention;

FIG. 2 is the visible light transmittance of the substrate in Example 1 of the present invention.

Wherein, 1. a flexible substrate, and 2. a conductive layer.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the present invention will be further described:

The technical solution of the present invention is to provide a substrate for a flexible light-emitting device. As shown in FIG. 1 , the structure of the device includes a flexible substrate 1 and a conductive layer 2 .

In the present invention, the flexible substrate 1 is the support of the conductive layer. It has good bending performance, certain ability to prevent water vapor and oxygen penetration, and has good chemical stability and thermal stability. The conductive layer 2 requires good The conductive ability, the flexible substrate and the conductive layer are composed of the following two methods: ① The flexible substrate is a transparent dielectric polymer material, the conductive layer is a silver nanowire film, and the gaps in the silver nanowire film filled with inorganic luminescent nanoparticles; ② the flexible substrate is a transparent dielectric polymer material doped with inorganic luminescent nanoparticles, the conductive layer is a silver nanowire film, and the gaps in the silver nanowire film are filled with Transparent dielectric polymer materials doped with phosphorescent nanoparticles including polyethylene, polymethyl methacrylate, polycarbonate, polyurethane, polyimide , PVC resin polyacrylic acid, polyaryletherketone, polyvinylidene fluoride, polyester, polyethylene naphthalate, polyacrylate, polyhexamethylene terephthalamide, polybutylene and polyvinyl alcohol.

The following are specific embodiments of the present invention:

Example 1

As the substrate structure shown in Figure 1, the flexible substrate 1 is made of polyethylene, and the conductive layer 2 is made of silver nanowire film, and the gaps of the silver nanowire film are filled with inorganic luminescent nanoparticles, and the size of the inorganic luminescent nanoparticles is 1nm.

The preparation method is as follows:

① Clean the silicon substrate whose surface roughness is less than 1nm, and dry it with dry nitrogen after cleaning;

② Disperse the silver nanowires evenly in the solvent, and prepare the silver nanowire film on the clean silicon substrate by spin coating. The rotation speed of the spin coating is 4000 rpm, the duration is 60 seconds, and the film thickness is about 80 nanometers;

③ Spray a solution containing phosphorescent nanoparticles on the silver nanowire film, place the silicon substrate in an environment of 80°C for 30 minutes, remove the remaining solvent in the silver nanowire film, and then spray polyethylene on the silver nanowire film;

④ Thermal curing treatment on the surface of the silicon substrate;

⑤Peel the silver nanowire film and the cured polyethylene layer off the surface of the silicon substrate to form a flexible conductive substrate;

⑥ Test the parameters of the transmittance, conductivity and surface morphology of the flexible conductive substrate.

Example 2

The substrate structure shown in Figure 1, the flexible substrate 1 adopts polymethyl methacrylate, the conductive layer 2 adopts a silver nanowire film, and the gaps of the silver nanowire film are filled with inorganic luminescent nanoparticles, and the inorganic luminescent nanoparticles The size is 5nm.

The preparation method is as follows:

① Clean the silicon substrate whose surface roughness is less than 1nm, and dry it with dry nitrogen after cleaning;

② Disperse the silver nanowires evenly in the solvent, and prepare the silver nanowire film on the clean silicon substrate by spraying;

③Spray a solution containing inorganic luminescent nanoparticles on the silver nanowire film, place the silicon substrate in an environment of 80°C for 30 minutes, remove the remaining solvent in the silver nanowire film, and then spray polymethyl ether on the silver nanowire film. Methyl acrylate;

④ Thermal curing treatment on the surface of the silicon substrate;

⑤Peel the silver nanowire film and the cured polymethyl methacrylate layer off the surface of the silicon substrate to form a flexible conductive substrate;

⑥ Test the parameters of the transmittance, conductivity and surface morphology of the flexible conductive substrate.

Example 3

The substrate structure shown in Figure 1, the flexible substrate 1 is made of polycarbonate, the conductive layer 2 is made of silver nanowire film, and the gaps of the silver nanowire film are filled with inorganic luminescent nanoparticles, and the size of the inorganic luminescent nanoparticles is 10nm .

The preparation method is as follows:

① Clean the silicon substrate whose surface roughness is less than 1nm, and dry it with dry nitrogen after cleaning;

② Disperse silver nanowires evenly in a solvent, and prepare silver nanowire films on a clean silicon substrate by screen printing;

③Spray a solution containing inorganic luminescent nanoparticles on the silver nanowire film, place the silicon substrate in an environment of 80°C for 30 minutes, remove the remaining solvent in the silver nanowire film, and then spray polycarbonate on the silver nanowire film ;

④ Thermal curing treatment on the surface of the silicon substrate;

⑤Peel the silver nanowire film and the cured polycarbonate layer off the surface of the silicon substrate to form a flexible conductive substrate;

⑥ Test the parameters of the transmittance, conductivity and surface morphology of the flexible conductive substrate.

Example 4

Substrate structure as shown in Figure 1, flexible substrate 1 adopts polyimide, and conductive layer 2 adopts silver nanowire thin film, and the gap of described silver nanowire thin film is filled with inorganic light-emitting nanoparticles, and the size of said inorganic light-emitting nanoparticles is 20nm.

The preparation method is as follows:

① Clean the silicon substrate whose surface roughness is less than 1nm, and dry it with dry nitrogen after cleaning;

② Disperse silver nanowires evenly in a solvent, and prepare silver nanowire films on a clean silicon substrate by inkjet printing;

③Spray a solution containing inorganic luminescent nanoparticles on the silver nanowire film, place the silicon substrate in an environment of 80°C for 30 minutes, remove the remaining solvent in the silver nanowire film, and then spray polyimide on the silver nanowire film. amine;

④ Thermal curing treatment on the surface of the silicon substrate;

⑤Peel the silver nanowire film and the cured polyimide layer off the surface of the silicon substrate to form a flexible conductive substrate;

⑥ Test the parameters of the transmittance, conductivity and surface morphology of the flexible conductive substrate.

Example 5

The substrate structure shown in Figure 1, the flexible substrate 1 adopts polyaryletherketone doped with phosphorescent nanoparticles, and the conductive layer 2 is a silver nanowire film, and the gaps of the silver nanowire film are filled with doped phosphorescent nanoparticles. For polyaryletherketone, the size of the inorganic luminescent nanoparticles is 30nm, and the doping mass ratio of the inorganic luminescent nanoparticles is 5%.

The preparation method is similar to Example 1.

Example 6

The substrate structure shown in Figure 1, the flexible substrate 1 adopts polyvinylidene fluoride doped with inorganic luminescent nanoparticles, the conductive layer 2 adopts a silver nanowire film, and the gaps of the silver nanowire film are filled with doped inorganic luminescent nanoparticles polyvinylidene fluoride, the size of the inorganic luminescent nanoparticles is 50nm, and the doping mass ratio of the inorganic luminescent nanoparticles is 10%.

The preparation method is similar to Example 1.

Example 7

The substrate structure shown in Figure 1, the flexible substrate 1 is made of polyester doped with phosphorescent nanoparticles, the conductive layer 2 is made of silver nanowire film, and the gaps of the silver nanowire film are filled with polymer doped with phosphorescent nanoparticles. ester, the size of the inorganic luminescent nanoparticles is 60nm, and the doping mass ratio of the inorganic luminescent nanoparticles is 15%.

The preparation method is similar to Example 1.

Example 8

The substrate structure shown in Figure 1, the flexible substrate 1 adopts polyethylene naphthalate doped with inorganic light-emitting nanoparticles, and the conductive layer 2 adopts a silver nanowire film, and the gaps of the silver nanowire film are filled with doped Polyethylene naphthalate of inorganic luminescent nanoparticles, the size of the inorganic luminescent nanoparticles is 70nm, and the doping mass ratio of the inorganic luminescent nanoparticles is 20%.

The preparation method is similar to Example 1.

Example 9

The substrate structure shown in Figure 1, the flexible substrate 1 adopts polyacrylate doped with phosphorescent nanoparticles, and the conductive layer 2 adopts a silver nanowire film, and the gaps of the silver nanowire film are filled with polyacrylate doped with phosphorescent nanoparticles. Polyacrylate, the size of the inorganic luminescent nanoparticles is 80nm, and the doping mass ratio of the inorganic luminescent nanoparticles is 30%.

The preparation method is similar to Example 1.

Example 10

The substrate structure shown in Figure 1, the flexible substrate 1 adopts polybutene doped with phosphorescent nanoparticles, and the conductive layer 2 adopts a silver nanowire film, and the gaps of the silver nanowire film are filled with polybutene doped with phosphorescent nanoparticles. Polybutene, the size of the inorganic luminescent nanoparticles is 100nm, and the doping mass ratio of the inorganic luminescent nanoparticles is 40%.

The preparation method is similar to Example 1.

Claims (1)

1. A method for preparing a substrate for a flexible light-emitting device, comprising a flexible substrate and a conductive layer, characterized in that the flexible substrate and the conductive layer are composed of one of the following two methods: ① the flexible substrate It is a transparent dielectric polymer material, the conductive layer is a silver nanowire film, and the gaps of the silver nanowire film are filled with inorganic luminescent nanoparticles; ②The flexible substrate is a transparent substrate doped with inorganic luminescent nanoparticles. The dielectric polymer material, the conductive layer is a silver nanowire film, and the gaps of the silver nanowire film are filled with a transparent dielectric polymer material doped with inorganic light-emitting nanoparticles, which is characterized in that it includes the following step: ① Clean the rigid substrate with surface roughness less than 1nm, and dry it with dry nitrogen after cleaning; ② Preparation of silver nanowire film on a clean substrate by spin coating or spray coating or self-assembly or inkjet printing or screen printing; ③ Spin-coat or spray-coat a transparent dielectric polymer material layer doped with inorganic luminescent nanoparticles on the silver nanowire film, or first spin-coat or drop-coat or spray-coat a solution containing inorganic luminescent nanoparticles, and then spin-coat or spray-coat a transparent Dielectric polymer material layer, the transparent dielectric polymer material includes polyethylene, polymethyl methacrylate, polycarbonate, polyurethane, polyimide, vinyl acetate polyacrylic acid, poly Aryl ether ketone, polyvinylidene fluoride, polyethylene naphthalate, polyacrylate, polyhexamethylene terephthalamide, polybutylene or polyvinyl alcohol; ④ heat curing treatment on the surface of the rigid substrate; ⑤Peel the silver nanowire film and the cured transparent dielectric polymer material layer or the transparent dielectric polymer material layer doped with inorganic luminescent nanoparticles off the surface of the rigid substrate to form a flexible conductive substrate; ⑥ Test the parameters of the transmittance, conductivity and surface morphology of the flexible conductive substrate.

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