TW201316583A - White organic light emitting diode (WOLED) structure - Google Patents

Abstract

A WOLED structure includes a hole-transporting layer, a host emission layer and a hole-blocking and electron-transporting layer. The host emission layer is doped with at least one blue guest material and at least one red guest material which can emit white light. In a preferred embodiment, the host emission layer is a blue host material layer or a Spiro-Pye host material layer.

Description

White light organic light emitting diode structure

The present invention relates to a white organic light emitting diode [WOLED] structure; in particular, to a white light organic light emitting diode structure having a single light-emission layer.

In general, an organic light emitting diode (OLED) can be widely applied to a flat panel display (FPD) having an emission electroluminescence layer. The luminescent layer has an organic compound material which is available for illuminating when a suitable current is applied.

In application, the organic light-emitting diode has the advantages of high luminance efficiency and low power consumption, and thus has the advantages of high brightness and power saving; in addition, the organic light-emitting diode With a light color, full color [full color], wide viewing angle and high response speed, its display speed only takes a few microseconds. Furthermore, the advantages of the organic light-emitting diode itself include flexibility and ease of manufacture. The most important advantage is that the organic light-emitting diode does not require a backlight member. Therefore, organic light-emitting diodes have a high potential use, and in particular, white light organic light-emitting diodes have a high potential use.

The basic structure of the organic light-emitting diode mainly includes a hole-transporting layer (HTL), an emissive layer (EL), and an electron-transporting layer (ETL). In an organic light-emitting diode, a hole is injected from the anode and electrons are injected from the cathode. When a hole is combined with electrons in the luminescent layer, the released energy produces excitation light in the desired area. In fact, organic light-emitting diodes need to balance the conduction of holes and electrons in order to generate excited photons in the desired area.

The carrier transport characteristics of the organic light-emitting diode affect its positional exciton formation zone, recombination process, and electroluminescence (EL) characteristics. Therefore, the energy level of the organic light-emitting diode material and the carrier mobility are the main considerations for fabricating the organic light-emitting diode. In addition, the structure of the organic light-emitting diode and the guest dopant (guest doping) are mainly used to modify the photophysical properties and electronic properties of the host light emitter [host].

The white light organic light emitting diode technology is only disclosed in some patents. For example, the new patent of "Two-wavelength light type white light organic light-emitting diode" of the Republic of China Patent Publication No. 556968 discloses a white light organic light-emitting diode comprising an electron transport layer, a hole barrier layer, and a a red/blue light emitting layer [light emitting layer], a hole transmitting layer, and a light enhancing layer or a light attenuating layer, the light enhancing layer or the light attenuating layer being located on one side of the red/blue light emitting layer [light emitting layer] The luminescence intensity of red light and blue light is equivalent to emit white light with better color purity. The light enhancement layer or light attenuating layer has a quantum well structure that forms a Bragg reflector in the organic light emitting diode to enhance or attenuate the red/blue light emitting layer.

Another conventional white light organic light emitting diode technology, such as the "White Light Organic Light Emitting Dielectric Structure" patent application of the Republic of China Patent Publication No. 201115805, discloses a white light organic light emitting diode structure comprising a hole transport layer, At least one blue light emitting layer, a plurality of hole blocking layers, at least one red light emitting layer, and an electron transport layer. The hole transport layer, the blue light emitting layer, the hole blocking layer, the red light emitting layer and the electron transport layer form an energy band, and the energy band has at least one type of quantum well structure, and the quantum well structure can gain the organic light emitting The luminescent properties of the polar body structure.

Another conventional white light organic light emitting diode technology, such as the patent application of "White light organic light emitting diode with red light doping layer and its manufacturing method" of the Republic of China Patent Publication No. 201018306, which discloses a red light blending The method for manufacturing a white light organic light-emitting diode of a hetero layer comprises the steps of preparing and patterning transparent conductive glass, surface treatment of plasma, forming a hole transport layer, forming a blue light emitting layer, forming a red light doped layer, and forming an electron injection The layer and the formation of the cathode electrode can be completed by a thermal evaporation machine, and the red-doped layer is doped with a red-light doping material in an electron-transporting material by co-evaporation.

Another conventional white light organic light-emitting diode technology, such as the patent application of "TANDEM WHITE OLED WITH EFFICIENT ELECTRON TRANSFER", US Patent No. US20100253209, discloses A white light emitting tandem organic light emitting diode device having spaced anodes and cathodes, comprising: first and second light emitting units disposed between a cathode and an anode; and an intermediate connector including first and second light emitting portions The n-type layer and the p-type layer between the units; and the onion-containing electron transport layer of the n-type layer adjacent to the intermediate connector, comprising at least 25% of a 7,10-diaryl-substituted fluoranthene compound, The onion compound does not have an aromatic ring bonded to the onion core in a cyclic form.

Another application of the white light organic light-emitting diode technology, such as the "WHITE OLED WITH BLUE LIGHT-EMITTING LAYERS" patent application of US Patent No. US20090146552, which discloses an organic The white light emitting device includes: a substrate; an anode and a cathode spaced apart from each other; a light emitting layer including a yellow dopant for emitting yellow light; and first and second blue light emitting layers, each of the blue light emitting layers having at least one different from the other A material of a blue light emitting layer.

Another conventional white light organic light-emitting diode technology, such as the "HIGH-PERFORMANCE TANDEM WHITE OLED" patent application of US Pat. No. US20080278066, which discloses that it has two intervals. The stacked OLED device of the electrode includes: first and second light emitting units disposed between the electrodes to generate different emission spectra, the first light emitting unit having a plurality of peaks at a wavelength greater than 500 nm and less than a wavelength There is substantially no emitted light at 480 nm, and the second illuminating unit generates substantially emitted light at a wavelength of less than 500 nm; and an intermediate connector disposed between the illuminating units.

Another application of the white light organic light-emitting diode technology, such as the patent application of "WHITE OLEDS HAVING COLOR-COMPENSATED ELECTROLUMINESCENT UNIT" with a color-compensated electroluminescent unit, is disclosed in US Pat. Disclosed is a tandem white light organic light emitting diode comprising an anode; a cathode; at least one broadband electrical excitation light unit disposed between the anode and the cathode, wherein the broadband electrical excitation light unit comprises at least one light emitting layer and is generated Having at least one color component that is less than the desired intensity; at least one color compensated electroluminescent light unit disposed between the anode and the cathode, wherein the color compensated electroluminescent light unit is selected to produce the at least one color component and Color component intensity; and an intermediate connector disposed between each adjacent electroluminescent light unit, wherein the intermediate connector is not directly connected to an external power source.

Another conventional white light organic light emitting diode technology, such as the white light organic light emitting diode formed by the combined monomer and the aggregated radiation, is disclosed in US Patent No. US20030124381 [WHITE LIGHT EMITTING OLEDS FROM COMBINED MONOMER AND AGGREGATE EMISSION] Patent application, which discloses an efficient organic light emitting diode [OLED], white light OLED [or WOLED]. The device utilizes two radiations within a single emission zone to adequately cover the visible spectrum. White light is achieved by the formation of agglomeration of two of the radiation in a single radiation zone at one of the radiation centers. It can constitute a simple, bright and efficient WOLED that exhibits a high color rendering index.

Another conventional white light organic light-emitting diode technology, such as the PCT Patent Publication No. WO2007141702, the "WHITE OLED WITH HIGH LUMEN EFFICACY" patent application, which discloses that the inclusion contains less than One of the 0.15 y color coordinates emits a white light emitting organic light emitting diode (100) of the blue light component (10). The organic light emitting diode may further comprise a yellow, red, and/or green light component (20, 30) and have a color temperature ranging between 2000 and 6000 K. A specific design of the blue light emitting component (10) comprises a glass substrate (40), an ITO anode (11), an Ag layer (12), an HTL (13), a blue light layer (14) and a cathode ( 15) A layered structure. The blue light-emitting layer (14) is preferably implemented as a microcavity capable of tuning wavelengths.

The aforementioned Republic of China Patent Publication No. 556968, Publication No. 201115805, Publication No. 201018306, US Patent Publication No. US20100253209, Publication No. US20090146552, Publication No. US20080278066, Publication No. US20060087225, Publication No. US20030124381, and PCT Patent Publication No. The WO2007141702 is only for reference to the technical background of the present invention and the state of the art is not limited to the scope of the present invention.

However, conventional white light organic light-emitting diodes still have a need to further improve their light-emitting characteristics to enhance their light-emitting brightness or light-emitting stability. Therefore, in addition to the appropriate activation of the dopant mode dopant fluorescent material, the white organic light-emitting diode can also use other technical means to improve its luminescent properties to meet the aforementioned potential needs.

In view of the above, the present invention provides a white light organic light emitting diode structure in which a blue light guest material and a red light guest material are doped in a body [host] light emitting layer in order to satisfy the above requirements. The main body light-emitting layer emits white light to improve the light-emitting luminance and light-emission stability of the conventional white light-emitting organic light-emitting diode.

The main object of the present invention is to provide a white light organic light emitting diode structure in which a blue guest material and a red light guest material are doped in a host light emitting layer, so that the main light emitting layer emits white light. In order to achieve the purpose of gain luminescence characteristics.

In order to achieve the above object, the white light organic light emitting diode structure of the present invention comprises: a hole transport layer; a body light emitting layer, which is doped with at least one blue light guest material and at least one red light guest material; and a hole blocking and An electron transport layer; wherein the dopant of the blue guest material and the red light guest material causes the main light emitting layer to emit white light.

In the preferred embodiment of the invention, the body light-emitting layer is a blue body light-emitting layer or a Spiro-Pye body light-emitting layer.

The blue guest material of the preferred embodiment of the invention is selected from the group consisting of: BCzVB

[1,4-bis[2-(3-N-ethylcarbazoryl)vinyl]benzene] material.

The red light guest material of the preferred embodiment of the invention is selected from the group consisting of: DCJTB

[4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethylju lolidin-4-ylvinyl)-4H-pyran] material.

The preferred embodiment of the present invention further includes an electron injecting layer disposed between the hole blocking and the electron transport layer and the aluminum metal layer.

The electron injecting layer of the preferred embodiment of the invention is made of a lithium fluoride [LiF] material.

A white light organic light emitting diode structure according to another embodiment of the present invention includes: a hole transport layer; a hole blocking layer; a body light emitting layer, which is doped with at least one blue light guest material and at least one red light guest material; a hole blocking and electron transport layer; wherein the dopant of the blue guest material and the red light guest material causes the main light emitting layer to emit white light.

In the preferred embodiment of the invention, the body light-emitting layer is a blue body light-emitting layer or a Spiro-Pye body light-emitting layer.

The blue guest material of the preferred embodiment of the invention is selected from the group consisting of: BCzVB

[1,4-bis[2-(3-N-ethylcarbazoryl)vinyl]benzene] material.

The red light guest material of the preferred embodiment of the invention is selected from the group consisting of: DCJTB

[4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethylju lolidin-4-ylvinyl)-4H-pyran] material.

The preferred embodiment of the present invention further includes an electron injecting layer disposed between the hole blocking and the electron transport layer and the aluminum metal layer.

In order to fully understand the present invention, the preferred embodiments of the present invention are described in detail below and are not intended to limit the invention.

The white light organic light-emitting diode structure of the preferred embodiment of the present invention can be widely applied to a flat panel display or a related art field thereof, and the related art is within the scope of the spirit and technical field of the present invention.

FIG. 1 is a schematic view showing the structure of a white organic light emitting diode according to a first preferred embodiment of the present invention. Referring to FIG. 1, the white organic light-emitting diode structure 1 of the first preferred embodiment of the present invention is disposed on a glass substrate 10, but it is not intended to limit the present invention. In addition, the glass substrate 10 has an indium tin oxide (ITO) coating material to form an ITO substrate layer 11 or have other transparent conductive oxide (TCO) materials. However, it is not intended to limit the invention. The ITO substrate layer 11 of the first preferred embodiment of the present invention is used as an anode of an organic light emitting diode, but it is not intended to limit the present invention. In addition, the white organic light-emitting diode structure 1 of the first preferred embodiment of the present invention has an aluminum metal layer 17 as a cathode of the organic light-emitting diode, but it is not intended to limit the present invention.

Referring to FIG. 1 again, the white light organic light emitting diode structure 1 of the first preferred embodiment of the present invention comprises a hole transport layer 12, a body light emitting layer 14, and a hole blocking and electron transport layer 15. It is sequentially arranged between the ITO substrate layer 11 [anode] and the aluminum metal layer 17 [cathode].

Referring to FIG. 1 again, the ITO substrate layer 11, the hole transport layer 12, the main body light-emitting layer 14, and the hole blocking and electron transport layer 15 of the first preferred embodiment of the present invention preferably use raw materials as physical gas. Formed by phase deposition [PVD, physic vapor deposition], for example: thermal evaporation, co-evaporation.

Referring again to FIG. 1, the ITO substrate layer 11 is bonded to one side of the hole transport layer 12. In addition, the main body light emitting layer 14 is located between the hole transport layer 12 and the hole blocking and electron transport layer 15 to sequentially form the hole transport layer 12, the main body light emitting layer 14, and the hole blocking and electron transport layer 15. Light-emitting diode structure.

Referring to FIG. 1 again, the hole transport layer 12 of the first preferred embodiment of the present invention is: NPB[N,N'-di(naphthalene-1-yl)-N, N'-diphenyl- The benzidine material is made to have a thickness of about 50 nm, but it is not intended to limit the invention.

Referring to FIG. 1 again, the main [host] light-emitting layer 14 of the first preferred embodiment of the present invention belongs to a blue body light-emitting layer or a Spiro-Pye body light-emitting layer, and the Spiro-Pye body light-emitting layer has Spiro-Pye main luminescent material, namely [2,7-di-pyrenyl-9,9-spirobifluorene] material. The bulk light-emitting layer 14 has a thickness of about 40 nm, but it is not intended to limit the invention.

Referring to FIG. 1 again, the body light-emitting layer 14 of the first preferred embodiment of the present invention is doped with at least one blue guest material [eg, 9 wt%] and at least one red light guest material. The blue guest material is selected from the group consisting of: BCzVB

[1,4-bis[2-(3-N-ethylcarbazoryl)vinyl]benzene] material.

In addition, the red light guest material is selected from: DCJTB

[4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethylju lolidin-4-ylvinyl)-4H-pyran] material.

Referring to FIG. 1 again, the hole blocking and electron transport layer 15 of the first preferred embodiment of the present invention has a thickness of about 30 nm, but it is not intended to limit the present invention. The hole blocking and electron transport layer 15 material is selected from the group consisting of: Bphen

Made of [4,7-diphenyl-1,10-phenanthroline] material.

Fig. 2 is a view showing the distribution of the energy band of the white organic light-emitting diode structure of the first preferred embodiment of the present invention. Referring to FIGS. 1 and 2, the ITO substrate layer 11, the hole transport layer 12, the main body light-emitting layer 14, the hole blocking and electron transport layer 15 and the aluminum metal layer 17 form an energy band, as shown in FIG. Show.

FIG. 3 is a graph showing the relationship between the luminous intensity and the voltage of the main light-emitting layer of the white organic light-emitting diode structure according to the first preferred embodiment of the present invention at various DCJTB concentrations. Referring to FIG. 3, the main body light-emitting layer 14 generates electroluminescence intensity at a concentration of 0.08%, 0.15%, 0.20%, and 0.30% of the DCJTB concentration, respectively, wherein 0.15% DCJTB dopant concentration and 9V drive are used. The maximum luminous intensity at a voltage was 5690 cd/m ² .

Fig. 4 is a graph showing the relationship between the current density and the voltage of the main light-emitting layer of the white organic light-emitting diode structure according to the first preferred embodiment of the present invention at various DCJTB concentrations. Referring to FIG. 4, the main body light-emitting layer 14 generates a current density at a concentration of 0.08%, 0.15%, 0.20%, and 0.30% of the DCJTB concentration, respectively, wherein a maximum current density is generated at a 0.15% DCJTB dopant concentration.

Fig. 5 is a graph showing the relationship between the efficiency and the current density of the main light-emitting layer of the white organic light-emitting diode structure according to the first preferred embodiment of the present invention at various DCJTB concentrations. Referring to FIG. 5, the main body light-emitting layer 14 has a relationship between efficiency and current density at a concentration of 0.08%, 0.15%, 0.20%, and 0.30% of DCJTB concentration, respectively, wherein the maximum density is generated at a concentration of 0.15% DCJTB dopant. Efficiency, and when the current density exceeds 200 mA/cm ² , its efficiency decreases.

Fig. 6 is a graph showing the relationship between the electroluminescence normalized intensity and the wavelength of the main light-emitting layer of the white organic light-emitting diode structure according to the first preferred embodiment of the present invention at various DCJTB concentrations. Referring to FIG. 6, the main body light-emitting layer 14 generates a normal light intensity at a concentration of 0.08%, 0.15%, 0.20%, 0.30% of the DCJTB concentration and a driving voltage of 9 V, wherein the concentration of the dopant in the 0.15% DCJTB is increased. At this time, the normal intensity of light emission at a wavelength of 450 nm to 550 nm also increases.

Attachment 1 discloses a C.I.E. color coordinate map of a white organic light-emitting diode constructed in accordance with a first preferred embodiment of the present invention at various DCJTB dopant concentrations. Referring to FIG. 1 , the main body light-emitting layer 14 is respectively made up of 0.08%, 0.15%, 0.20%, and 0.30% of DCJTB concentration, and is labeled as Device D-1 and Device D-2. Device D-3, Device D-4.

The color coordinates of Device D-1 at 6V, 7V, 8V, and 9V are (0.28, 0.30), (0.29, 0.31), (0.29, 0.31), (0.30, 0.31), respectively, as indicated by black dots. . Next, the color coordinates of Device D-2 at 6V, 7V, 8V, and 9V are respectively (0.33, 0.33), (0.33, 0.33), (0.33, 0.34), (0.33, 0.34), such as black dots. As shown, it emits pure white light. Next, the color coordinates of Device D-3 at 6V, 7V, 8V, and 9V are respectively (0.42, 0.36), (0.40, 0.35), (0.40, 0.35), (0.40, 0.36), such as black dots. Shown. Next, the color coordinates of Device D-4 at 6V, 7V, 8V, and 9V are respectively (0.50, 0.41), (0.49, 0.40), (0.48, 0.40), (0.47, 0.39), such as black dots. Shown.

FIG. 7 is a schematic view showing the structure of a white organic light emitting diode according to a second preferred embodiment of the present invention. Referring to FIG. 7, the white light organic light emitting diode structure 1 of the second preferred embodiment of the present invention comprises a hole transport layer 12, a body light emitting layer 14, a hole blocking and electron transport layer 15 and a The electron injection layer 16 is sequentially arranged between the ITO substrate layer 11 [anode] and the aluminum metal layer 17 [cathode]. With respect to the first embodiment, the second preferred embodiment adds the electron injecting layer 16 , and the rest is in reference to the first embodiment, which is incorporated herein by reference.

Referring to FIG. 7 again, the electron injecting layer 16 is disposed between the hole blocking layer and the electron transport layer 15 and the aluminum metal layer 17. The electron injecting layer 16 is made of a lithium fluoride [LiF] material having a suitable thickness, for example, 0.5 nm, 1.0 nm, 2.0 nm, 3.0 nm.

Figure 8 is a view showing the distribution of the energy band of the white organic light-emitting diode structure of the second preferred embodiment of the present invention. Referring to FIGS. 7 and 8, the ITO substrate layer 11, the hole transport layer 12, the main body light-emitting layer 14, the hole barrier and electron transport layer 15, the electron injection layer 16, and the aluminum metal layer 17 form an energy band. As shown in Figure 8.

Fig. 9 is a graph showing the relationship between the luminous intensity and the voltage at various thicknesses of the electron injecting layer [LiF] in the white organic light emitting diode structure of the second preferred embodiment of the present invention. Referring to FIG. 9, the thickness of the electron injecting layer 16 is 0.5 nm, 1.0 nm, 2.0 nm, and 3.0 nm, respectively. When the electron injecting layer 16 was selected to have a thickness of 1.0 nm at a driving voltage of 8 V, it produced a maximum luminous intensity of 2,1800 cd/m ² .

Fig. 10 is a graph showing the relationship between current density and voltage at various thicknesses of the electron injecting layer [LiF] of the white organic light emitting diode structure of the second preferred embodiment of the present invention. Referring to FIG. 10, the thickness of the electron injecting layer 16 is 0.5 nm, 1.0 nm, 2.0 nm, and 3.0 nm, respectively. When the electron injecting layer 16 is selected to have a thickness of 1.0 nm, it produces a maximum current density. Once the thickness of the electron injecting layer 16 exceeds 1.0 nm, the current density decreases.

Figure 11 is a graph showing the relationship between the normal intensity of electroluminescence and the wavelength at various driving voltages [bias] of the electron injecting layer [LiF] in the white organic light emitting diode structure of the second preferred embodiment of the present invention. Referring to FIG. 11, when the thickness of the electron injecting layer 16 is 1.0 nm, various electroluminescence normal intensities are generated at driving voltages of 5 V, 6 V, 7 V, and 8 V, respectively.

Fig. 12 is a graph showing the relationship between the normal intensity of electroluminescence and the wavelength at various thicknesses of the electron injecting layer [LiF] in the white light organic light emitting diode structure of the second preferred embodiment of the present invention. Referring to FIG. 12, the electron injecting layer 16 generates various electroluminescence normal intensities at a driving voltage of 8 V at 0.5 nm, 1.0 nm, 2.0 nm, and 3.0 nm, respectively. When the electron injecting layer 16 is increased in thickness, its blue light intensity is lowered. On the contrary, when the electron injecting layer 16 is increased in thickness, its red light intensity is increased.

Attachment 2 discloses a C.I.E. color coordinate map of a thickness of various electron injecting layer structures of a white light organic light emitting diode according to a second preferred embodiment of the present invention. Referring to FIG. 2, the electron injection layer 16 is made of four devices at 0.5 nm, 1.0 nm, 2.0 nm, and 3.0 nm thickness, and is labeled as Device E-1, Device E-2, and Device E-3. , Device E-4.

The color coordinates of Device E-1 at 5V, 6V, 7V, and 8V are (0.29, 0.35), (0.25, 0.31), (0.23, 0.30), (0.22, 0.28), respectively, as indicated by black dots. . Next, the color coordinates of Device E-2 at 5V, 6V, 7V, and 8V are respectively (0.29, 0.34), (0.27, 0.33), (0.27, 0.32), (0.27, 0.32), such as black dots. Shown. Next, the color coordinates of Device E-3 at 5V, 6V, 7V, and 8V are respectively (0.35, 0.39), (0.33, 0.37), (0.31, 0.36), (0.30, 0.34), such as black dots. Shown. In addition, the color coordinates of Device E-4 at 5V, 6V, 7V, and 8V are respectively (0.34, 0.37), (0.32, 0.36), (0.31, 0.36), (0.31, 0.35), such as black spots. Shown.

Figure 13 is a block diagram showing the construction of a white organic light-emitting diode according to a third preferred embodiment of the present invention. Referring to FIG. 13, the white light organic light emitting diode structure 1 of the third preferred embodiment of the present invention comprises a hole transport layer 12, a hole blocking layer 13, a body light emitting layer 14, and a hole blocking. And an electron transport layer 15 and an electron injection layer 16 which are sequentially arranged between the ITO substrate layer 11 [anode] and the aluminum metal layer 17 [cathode]. With respect to the second embodiment, the third preferred embodiment adds the arrangement of the hole blocking layer 13, and the rest is in reference to the second embodiment, which is hereby incorporated by reference.

Referring to FIG. 13 again, the hole blocking layer 13 is disposed between the hole transport layer 12 and the main body light-emitting layer 14. The material of the hole blocking layer 13 is selected from the group consisting of CBP [4, 4'-bis (carbazol-9-yl) biphenyl] having a suitable thickness, for example, 0.5 nm, 1.0 nm, 2.0 nm, 3.0 nm.

Fig. 14 is a view showing the distribution of the energy band of the white organic light-emitting diode structure of the third preferred embodiment of the present invention. Referring to FIGS. 13 and 14, the ITO substrate layer 11, the hole transport layer 12, the hole blocking layer 13, the main body light-emitting layer 14, the hole blocking and electron transporting layer 15, the electron injecting layer 16, and the aluminum metal layer. 17 forms an energy band as shown in Fig. 14.

Fig. 15 is a graph showing the relationship between the luminous intensity and the voltage at various thicknesses of the hole blocking layer [CBP] in the white organic light-emitting diode structure of the third preferred embodiment of the present invention. Referring to FIG. 15, the thickness of the hole blocking layer 13 is 0.5 nm, 1.0 nm, 2.0 nm, and 3.0 nm, respectively. At a driving voltage of 8 V, when the hole blocking layer 13 was selected to have a thickness of 1.0 nm, it produced a maximum luminous intensity of 17100 cd/m ² . Once the thickness of the hole blocking layer 13 exceeds 1.0 nm, the luminous intensity decreases.

Figure 16 is a graph showing the relationship between current density and voltage at various thicknesses of the hole blocking layer [CBP] of the white organic light-emitting diode structure of the third preferred embodiment of the present invention. Referring to FIG. 16, the thickness of the hole blocking layer 13 is 0.5 nm, 1.0 nm, 2.0 nm, and 3.0 nm, respectively. When the hole barrier layer 13 is selected to be 0.5 nm thick [thinthmost], it produces a maximum current density.

Figure 17 is a graph showing the relationship between the normal intensity of electroluminescence and the wavelength at various driving voltages [bias] of the hole blocking layer [CBP] in the white organic light-emitting diode structure of the third preferred embodiment of the present invention. Referring to FIG. 17, the thickness of the hole blocking layer 13 is 1.0 nm, and various electroluminescence normal intensities are generated at driving voltages of 5 V, 6 V, 7 V, 8 V, and 9 V, respectively. When the hole blocking layer 13 is increased in thickness, its blue light intensity is increased.

Attachment 3 discloses a C.I.E. color coordinate map of the thickness of various hole blocking layers of the white light organic light emitting diode constructed in the third preferred embodiment of the present invention. Referring to the attached picture 3, the hole blocking layer 13 is made of four devices at 0.5 nm, 1.0 nm, 2.0 nm, and 3.0 nm thickness, and is labeled as Device F-1, Device F-2, Device F-. 3. Device F-4.

The color coordinates of Device F-1 at 5V, 6V, 7V, and 8V are (0.41, 0.38), (0.38, 0.36), (0.35, 0.34), (0.34, 0.33), respectively, as indicated by black dots. . Next, the color coordinates of Device F-2 at 5V, 6V, 7V, and 8V are respectively (0.36, 0.37), (0.35, 0.37), (0.33, 0.36), (0.33, 0.35), such as black dots. Shown. Next, the color coordinates of Device F-3 at 5V, 6V, 7V, and 8V are respectively (0.50, 0.42), (0.47, 0.41), (0.43, 0.39), (0.41, 0.38), such as black dots. Shown. Next, the color coordinates of Device F-4 at 5V, 6V, 7V, and 8V are respectively (0.52, 0.43), (0.48, 0.42), (0.44, 0.40), (0.41, 0.39), such as black dots. Shown.

The above experimental data is preliminary experimental results obtained under specific conditions, which are only used to easily understand or refer to the technical content of the present invention, and other experiments are still required. The experimental data and its results are not intended to limit the scope of the invention.

The foregoing preferred embodiments are merely illustrative of the invention and the technical features thereof, and the techniques of the embodiments can be carried out with various substantial equivalent modifications and/or alternatives; therefore, the scope of the invention is subject to the appended claims. The scope defined by the scope shall prevail.

1. . . White light organic light emitting diode structure

10. . . glass substrate

11. . . ITO substrate layer

12. . . Hole transport layer

13. . . Hole blocking layer

14. . . Main body light emitting layer

15. . . Hole blocking and electron transport layer

16. . . Electron injection layer

17. . . Aluminum metal layer

FIG. 1 is a schematic view showing the structure of a white organic light emitting diode according to a first preferred embodiment of the present invention.

Fig. 2 is a schematic view showing the distribution of the energy band of the white organic light-emitting diode structure of the first preferred embodiment of the present invention.

Fig. 3 is a graph showing the relationship between the luminous intensity and the voltage of the main light-emitting layer of the white organic light-emitting diode structure according to the first preferred embodiment of the present invention, which is mixed with various DCJTB concentrations.

Fig. 4 is a graph showing the relationship between the current density and the voltage of the main light-emitting layer of the white organic light-emitting diode structure according to the first preferred embodiment of the present invention at various DCJTB concentrations.

Fig. 5 is a graph showing the relationship between the efficiency of the main light-emitting layer of the white organic light-emitting diode structure of the first preferred embodiment of the present invention and the current density at various DCJTB concentrations.

Fig. 6 is a graph showing the relationship between the normal intensity of electroluminescence and the wavelength of a main light-emitting layer of a white organic light-emitting diode structure according to a first preferred embodiment of the present invention, which is doped with various DCJTB concentrations.

Figure 7 is a schematic view showing the structure of a white light organic light emitting diode according to a second preferred embodiment of the present invention.

Figure 8 is a schematic view showing the distribution of the energy band of the white organic light-emitting diode structure of the second preferred embodiment of the present invention.

Fig. 9 is a graph showing the relationship between the luminous intensity and the voltage at various thicknesses of the electron injecting layer in the white organic light emitting diode structure of the second preferred embodiment of the present invention.

Fig. 10 is a graph showing the relationship between current density and voltage at various thicknesses of the electron injecting layer in the white light organic light emitting diode structure of the second preferred embodiment of the present invention.

Figure 11 is a graph showing the relationship between the normal intensity of electroluminescence and the wavelength at various voltages of the electron injecting layer in the white light organic light emitting diode structure of the second preferred embodiment of the present invention.

Fig. 12 is a graph showing the relationship between the normal intensity of electroluminescence and the wavelength at various thicknesses of the electron injecting layer in the white light organic light emitting diode structure of the second preferred embodiment of the present invention.

Figure 13 is a schematic view showing the structure of a white light organic light emitting diode according to a third preferred embodiment of the present invention.

Figure 14 is a schematic view showing the distribution of the energy band of the white organic light-emitting diode structure of the third preferred embodiment of the present invention.

Fig. 15 is a graph showing the relationship between the luminous intensity and the voltage at various thicknesses of the hole barrier layer in the white organic light-emitting diode structure of the third preferred embodiment of the present invention.

Figure 16 is a graph showing the relationship between current density and voltage at various thicknesses of the hole barrier layer of the white organic light-emitting diode structure of the third preferred embodiment of the present invention.

Figure 17 is a graph showing the relationship between the normal intensity of electroluminescence and the wavelength at various voltages of the hole blocking layer of the white organic light-emitting diode structure of the third preferred embodiment of the present invention.

Attachment 1: The white light organic light-emitting diode of the first preferred embodiment of the present invention is constructed in C.I.E. color coordinates of various DCJTB dopant concentrations.

Attachment 2: The white light organic light-emitting diode of the second preferred embodiment of the present invention is constructed in a C.I.E. color coordinate map of various electron injection layer thicknesses.

Attachment 3: The white light organic light-emitting diode of the third preferred embodiment of the present invention is constructed in a C.I.E. color coordinate map of various hole barrier layer thicknesses.

1. . . White light organic light emitting diode structure

10. . . glass substrate

11. . . ITO substrate layer

12. . . Hole transport layer

14. . . Main body light emitting layer

15. . . Hole blocking and electron transport layer

17. . . Aluminum metal layer

Claims (10)

A white organic light emitting diode structure comprising: a hole transport layer; a host light emitting layer, which is doped with at least one blue light guest material and at least one red light guest material; and a hole blocking and electron transport layer; The dopant of the blue guest material and the red light guest material causes the bulk light emitting layer to emit white light. The white light organic light emitting diode structure according to claim 1, wherein the main light emitting layer is a blue light emitting layer or a Spiro-Pye main emitting layer. The white light organic light emitting diode structure of claim 1, wherein the blue light guest material is selected from the group consisting of BCzVB materials. The white light organic light emitting diode structure of claim 1, wherein the red light guest material is selected from the group consisting of DCJTB materials. The white light organic light emitting diode structure according to claim 1, further comprising an electron injecting layer disposed between the hole blocking layer and the electron transporting layer and the aluminum metal layer. A white light organic light emitting diode structure comprising: a hole transport layer; a hole blocking layer; a body light emitting layer, which is doped with at least one blue light guest material and at least one red light guest material; and a hole blocking And an electron transport layer; wherein the dopant of the blue guest material and the red light guest material causes the main light emitting layer to emit white light. The white light organic light emitting diode structure according to claim 6, wherein the main light emitting layer is a blue light emitting layer or a Spiro-Pye main emitting layer. The white light organic light emitting diode structure of claim 6, wherein the blue light guest material is selected from the group consisting of BCzVB materials. The white light organic light emitting diode structure of claim 6, wherein the red light guest material is selected from the group consisting of DCJTB materials. The white light organic light emitting diode structure according to claim 6 of the patent application, further comprising an electron injecting layer disposed between the hole blocking layer and the electron transport layer and the aluminum metal layer.