TWM482859U - Organic light emitting diode - Google Patents

Description

Organic light-emitting diode

The present invention is an organic light-emitting diode, in particular, an organic light-emitting diode that is coated with an organic material by spin coating or doctor blade and reduces the pressure of the environment in which the substrate is placed.

Organic Light Emitting Diode (OLED) is considered to be another important type of flat panel display because of its self-illumination, thinness and wide operating temperature range.

The structure of the organic light-emitting diode is mainly composed of an indium tin oxide (ITO) substrate, an organic material layer, and a cathode layer. The organic material layer usually includes an organic light emitting layer (EML), an electron injection layer (Electron Inject Layer (EIL), an electron transport layer (ETL), and a hole transport layer (HTL). And a structure such as a Hole Inject Layer (HIL).

In the production of the above various structures, the first is to use a semiconductor coating technology to deposit various organic materials on the ITO substrate, and then pre-bake the substrate, volatilize the solvent content of the organic material on the substrate, and then solid-bake the cured organic material. The organic layer is fabricated and the electrode is completed, and finally the encapsulation process is performed to complete the fabrication of the organic light-emitting diode. When the organic light emitting diode is fabricated on the substrate, a mask having a plurality of openings may be disposed on the surface of the ITO substrate, and then the organic material is coated on the surface of the mask. The organic material is filled into the opening of the mask to make the surface of the substrate After forming a plurality of organic display units, the process of pre-baking, solid baking and packaging can be performed.

However, when the organic material is filled in the opening of the mask, the organic material penetrates between the mask and the substrate due to its own fluidity, and the organic material overflows to the outside of the opening, so that the organic material adheres to the mask and Between the substrates. In addition, if the substrate collides and vibrates due to movement during the manufacturing process, or the mask is removed from the surface of the substrate, the organic material is damaged by adhesion to the mask and the substrate, thereby affecting the light quality. In addition, after the organic material is deposited on the substrate, it must be pre-baked and solid-baked for a certain period of time to complete the entire production process, which makes the production time longer and the cost higher.

Therefore, the main purpose of the present invention is to provide an organic light-emitting diode which can reduce the overflow phenomenon of organic materials in the manufacturing process and improve the process quality.

Another object of the present invention is to provide an organic material layer of an organic light-emitting diode which can shorten manufacturing time and reduce manufacturing cost.

In order to achieve the above object, the present invention provides an organic light emitting diode comprising at least a substrate and an organic material layer formed on a substrate, the organic material layer being composed of an organic material having a solvent. The organic material is formed on the substrate by spin coating or blade coating while reducing the solvent content of the organic material by reducing the pressure of the environment in which the substrate is placed. The organic light emitting diode is completed by the following steps: 1. coating the organic material with the solvent on the substrate by spin coating or knife coating; second, reducing the pressure of the environment in which the substrate is placed, to reduce the organic The solvent content of the material. By the above-mentioned method of reducing the pressure, the creation can reduce the overflow phenomenon of the organic material layer in the manufacturing process, and at the same time achieve the improvement of the process quality, shorten the manufacturing time, and reduce the manufacturing cost. purpose.

In the following, regarding the characteristics, implementation and efficacy of the present creation, the best embodiment is implemented in conjunction with the drawings.

10‧‧‧Substrate

20‧‧‧Organic/organic layer

21‧‧‧Organic Materials Unit

30‧‧‧bearing abutments

40‧‧‧ nozzle

50‧‧‧ hot plate

60‧‧‧ scraper

70‧‧‧ mask

71‧‧‧Opening

The first figure is a flow chart of the manufacturing method of the first embodiment of the organic light-emitting diode of the present invention.

The second figure is a schematic diagram of the spin coating of the organic light-emitting diode of the present invention.

The third figure is a schematic diagram of the organic light-emitting diode blade coating of the present invention.

The fourth figure is a schematic view of the second embodiment of the organic light-emitting diode of the present invention, mainly showing the state in which the organic material is filled in the mask.

The fifth figure is a schematic view of the second embodiment of the present invention, mainly showing the state in which the substrate is provided with a plurality of organic material units.

The sixth drawing is a flow chart of the manufacturing method of the third embodiment of the present invention.

In the following, a number of preferred embodiments are listed in conjunction with the drawings for a detailed description of the organic light-emitting diode of the present invention. The brief description of each of the drawings is as follows: The first figure is the first organic light-emitting diode of the present invention. Flow chart of the process method of the embodiment. The second figure is a schematic diagram of the spin coating of the organic light-emitting diode of the present invention. The third figure is a schematic diagram of the organic light-emitting diode blade coating of the present invention. The fourth figure is a schematic view of the second embodiment of the organic light-emitting diode of the present invention, mainly showing the state in which the organic material is filled in the mask. The fifth figure is a schematic view of the second embodiment of the present invention, mainly showing the state in which the substrate is provided with a plurality of organic material units. The sixth figure is a flow chart of the process method of the third embodiment of the present creation.

Please refer to the first figure, which is a flow chart of a process method for the first embodiment of the organic light-emitting diode of the present invention, which is mainly used for manufacturing a monolithic organic light emitting diode (OLED). The method comprises the following steps: Step 1: Coating. First, a cleaned indium tin oxide (ITO) substrate is placed in a chamber, and an organic material is coated on the surface of the substrate to form an organic material layer on the surface of the substrate. The organic material layer can be an electron injection layer or an electron. The transport layer, the light-emitting layer, the hole transport layer, or the hole injection layer. The substrate can serve as an anode layer of an organic light emitting diode.

Step 2: Decompression. When the pressure in the chamber is lowered and the pressure in the chamber is lowered, the evaporation rate of the solvent contained in the organic material is also accelerated. In this embodiment, the pressure in the chamber is reduced to below 1 atmosphere. When the vapor pressure of the solvent contained in the organic material is large, the organic material is dried in a reduced state, and another organic material layer may be further coated. If the organic material cannot be cured after decompression, the following steps can be performed: Step 3: Drying and pre-baking. The solvent content in the organic material layer can be further reduced by moving the decompressed substrate into another chamber and raising the temperature of the substrate in the environment to about 100 degrees Celsius. Dry pre-baking can also make the surface of the organic material layer relatively flat.

Step 4: Solid roast. The substrate and the organic material layer are dried at a temperature higher than the drying pre-bake stage to minimize the solvent content while curing the organic material layer. After the organic material layer is cured, as shown in the first figure, another layer of the organic material layer may be coated by repeating steps 1 through 4, etc. until the desired composition is coated and stacked.

Step 5: Make a cathode layer. A metal layer is disposed on the surface of the organic material layer by a coating technique, and the metal layer can serve as a cathode layer of the organic light emitting diode.

Step six: Encapsulation. Cover the solidified organic with a glass cover and UV glue The material layer completes the fabrication of a single-piece organic light-emitting diode.

Please refer to the second and third figures. The second figure is a schematic diagram of the spin coating of the organic light-emitting diode of the present invention. The third figure is a schematic diagram of the organic light-emitting diode blade coating of the present invention. As shown in the second figure, the organic light emitting diode can be spin-coated, and includes a carrier base 30 and a nozzle 40. The carrier base 30 is used to carry the substrate 10, and the nozzle 40 is used for output. The organic material 20 is disposed on the substrate 10, and when the nozzle 40 outputs the organic material 20 to the substrate 10, the carrier base 30 carries the substrate 10 and drives the substrate 10 to rotate at a fixed point to enable the organic material 20 to be A spin coating method is uniformly formed on the substrate 10. As shown in the third figure, the organic light-emitting diode can be blade-coated, and includes a hot plate 50 and a scraper 60 for carrying the substrate 10 and uniformly heating the substrate 10. The doctor blade 60 is used to output the organic material 20 to the substrate 10 while homogenizing the organic material 20 to form the organic material layer 20.

Please refer to the fourth embodiment and the fifth figure again, which are respectively schematic diagrams of the second embodiment of the organic light-emitting diode of the present invention, mainly showing the state in which the organic material is filled in the mask and the second embodiment of the present creation. The schematic diagram mainly shows the state in which the substrate is provided with a plurality of organic material units. It is mainly used for batch production of a plurality of organic light-emitting diodes, and the method comprises the following steps: Step 1: First, a cleaned ITO substrate 10 is placed in a chamber, and a mask having a plurality of openings 71 is further disposed. 70 is disposed on the surface of the substrate 10.

Step 2: The organic material 20 is coated on the mask 70, and the organic material 20 is filled into each of the openings 71, and a plurality of organic material units 21 can be formed on the surface of the substrate 10.

Step 3: reduce the pressure in the chamber. When the pressure in the chamber decreases, the evaporation rate of the solvent contained in the organic material unit 21 on the surface of the substrate 10 is also accelerated, so that the solvent content can be relatively high. Reduce quickly. In the present embodiment, when the pressure in the chamber drops below about 0.5 atm, the solvent content can be reduced from about 90% to about 10% or less.

Step 4: The substrate 10 after the pressure reduction treatment is placed in another chamber, and the pre-baked substrate 10 and each organic material unit 21 are dried, so that the solvent content of each organic material unit 21 is continuously lowered. The pre-baking temperature in this embodiment is about 150 degrees Celsius, and the pre-baking time is about 30 seconds. After pre-baking, the solvent content can be reduced to less than 1%.

Step 5: Baking the substrate 10 at a higher temperature to cure the organic material layer 20. After the organic material layer 20 is cured, another layer of the organic material layer 20 may be applied by repeating steps 2 through 5 until the desired composition is coated and the stack is completed. Step 6: forming a cathode layer on the surface of the organic material layer 20. Step 7: The mask 70 is removed and the substrate 10 is packaged, and then the organic material units 21 are separated to form a plurality of organic light-emitting diodes.

According to the manufacturing method of the above preferred embodiment, whether only a single organic light emitting diode or a plurality of organic light emitting diodes are formed at a time, when the organic material is disposed on the ITO substrate and then subjected to a decompression process, the organic material is contained. The solvent content can be reduced relatively quickly. When the solvent content is rapidly decreased, as in the second step of the second embodiment, the flow rate of the organic material can be relatively slow, so that the overflow phenomenon of the material is greatly reduced. If there is a slight collision or vibration during the movement of the substrate to another chamber, or if the mask is removed from the surface of the substrate, the organic material layer is not damaged by adhesion to the mask and the substrate.

Furthermore, when the organic material is subjected to a decompression process, the solvent contained in the material evaporates faster, not only can be directly dried and solidified, but the temperature of subsequent pre-baking can be lowered, and the time of pre-baking or solid-baking is also reduced. Can be shortened. Thereby, by using the above-mentioned decompression process, the creation can reduce the overflow phenomenon of the organic material layer in the manufacturing process and improve the process quality. And to achieve the purpose of shortening the manufacturing time and reducing the manufacturing cost. Further, as shown in the sixth embodiment, the method for manufacturing the organic material layer provided in the third embodiment of the present invention is characterized in that the surface of the substrate is coated with an organic material, and the substrate and the organic material are simultaneously heated under reduced pressure to make the organic After the solvent in the material is volatilized, the organic material can be solidified or cured by a pre-bake or solid-bake step, which can also achieve the above-mentioned creation.

Although the embodiments of the present invention are disclosed as described above, it is not intended to limit the present invention, and any person skilled in the art may, without departing from the spirit and scope of the present invention, the shapes, structures, and features described in the scope of the present application. And the quantity can be changed in a small amount, and therefore the scope of patent protection of this creation is subject to the definition of the scope of the patent application attached to this specification.

10‧‧‧Substrate

20‧‧‧Organic/organic layer

30‧‧‧bearing abutments

40‧‧‧ nozzle

Claims (9)

An organic light emitting diode comprising: at least: a substrate; and an organic material layer formed on the substrate, the organic material layer being composed of an organic material having a solvent; wherein the organic material is rotated A coating or doctor blade coating is formed on the substrate while reducing the solvent content of the organic material by reducing the pressure of the environment in which the substrate is placed. The organic light-emitting diode according to claim 1, wherein the pressure of the environment in which the substrate is placed is lowered to 0.5 or less than atmospheric pressure. The organic light-emitting diode according to claim 1, wherein the substrate and the organic material layer are dried after reducing the pressure of the environment in which the substrate is placed. The organic light-emitting diode according to claim 3, wherein the substrate and the organic material layer are dried at a temperature of 100 or 150 degrees Celsius. The organic light-emitting diode according to claim 1, wherein the substrate and the organic material layer are heated while reducing the pressure of the environment in which the substrate is placed. The organic light-emitting diode according to claim 1, wherein the organic material can form an electron injection layer, an electron transport layer, a light-emitting layer, a hole transport layer, or a hole injection layer. The organic light-emitting diode according to claim 1, further comprising a mask having at least one opening, coating the organic material having the solvent on the mask, and filling the organic material into the opening And removing the mask such that the surface of the substrate forms the organic material layer having at least one organic material unit. The organic light-emitting diode according to claim 1, further comprising a carrier base and a nozzle, wherein the carrier base is configured to carry the substrate, and the nozzle is configured to output the organic material On the substrate, when the nozzle outputs the organic material on the substrate, the bearing base carries the substrate and drives the substrate to rotate at a fixed point, so that the organic material is uniformly formed on the substrate by spin coating. The organic light emitting diode according to claim 1, further comprising a hot plate for carrying the substrate and uniformly heating the substrate, the scraping blade for outputting the organic material The substrate is simultaneously homogenized to form the organic material layer.