Red-green OLED device and white-light OLED device

Abstract

The invention belongs to the technical field of organic light-emitting devices, and particularly relates to a red-green OLED device and a white-light OLED device. In the OLED device provided by the invention, a red light emitting unit uses bipolar double-host materials: an n-type red light host material and a p-type red light host material; and meanwhile, the green light emitting unit also uses bipolar double-main-body materials: an n-type green light main-body material and a p-type green light main-body material. According to the invention, the mass ratio of the n-type main body material to the p-type main body material in the red light emitting unit and the green light emitting unit can be adjusted to regulate and control the recombination area of current carriers, so that the requirements of high efficiency and low color cast of the device are met. According to the invention, the red light emitting unit and the green light emitting unit, namely the red-green single-layer structure, are adjusted, and the structure is suitable for the red-green light emitting layer in the laminated white light structure.

Description

Technical Field

[0001] The invention belongs to the technical field of organic electroluminescent devices, and in particular relates to a red-green OLED device and a white-light OLED device. Background Art

[0002] Silicon-based organic light-emitting diode (OLED) microdisplay is a new display technology that uses active light-emitting devices OLED to be fabricated on a silicon-based CMOS drive circuit substrate. It has been widely used in military markets such as machine-worn helmets, gun sights, and night vision goggles, and has extremely broad application prospects in the AR / VR market.

[0003] In the stacked white light structure used in the current silicon-based OLED microdisplay, the structure of the organic functional layer is basically as follows: Figure 1 As shown, Figure 1 The red-green light-emitting layer (RG-EML) shown in the figure is formed by using red and green light guest materials, that is, red light guest material (RD) and green light guest material (GD) are co-doped into the same host material (Host). The energy transfer process in the red and green light-emitting layers of this structure is as follows: Figure 2 As shown in the figure, there are three energy processes: ① Energy is transferred from the Host to the green light guest material (GD); ② Energy is transferred from the Host to the red light guest material (RD); ③ Energy is transferred from the green light guest material (GD) to the red light guest material (RD). Among the above three energy transfer processes, process ① has the most complete energy transfer, while there is energy loss in process ② and process ③, which leads to reduced device performance. In addition, since there is also energy transfer between the red light guest material and the green light guest material (process ③), the doping ratio of red light will be very low. Generally, the doping concentration of the red light guest is <0.5%, which will cause the process window to be too small during the production process, resulting in a low product yield.

[0004] In order to improve the efficiency of silicon-based OLED microdisplay devices, Figure 2 The energy transfer loss of process ② and process ③ in the above process is reduced or eliminated, and the structure of the red and green light-emitting layers is changed to use two main materials: red light main material (RH) and green light main material (GH), corresponding to two guest materials: red light guest material (RD) and green light guest material (GD). At this time, the structure of the red and green light-emitting layers is as follows: Figure 3 As shown, Figure 1 The red and green light-emitting layer structure in the embodiment is set as a red light-emitting unit and a green light-emitting unit. At this time, the energy transfer process is as follows: Figure 4 The advantages of this device in which the red light emitting unit and the green light emitting unit are separately arranged are: the efficiency of the device can be improved; and the process window of the product can be expanded at the same time.

[0005] However, the device with separate red and green light emitting units also has obvious disadvantages: the chromaticity drift of the device is large, and the red and green light emitting units of the device have high requirements for the selection of materials. The carrier recombination area (luminous area) must meet the requirements of the green and red light emitting units at the same time to ensure that the chromaticity remains unchanged under different brightness conditions, and the red and green light emitting units need to emit light at the same time. These disadvantages make the device with separate red and green light emitting units extremely difficult to produce in the actual production process, and it is not suitable for industrial expansion and application. Summary of the invention

[0006] The purpose of the present invention is to provide a red-green OLED device and a white light OLED device. The device provided by the present invention can reduce the color deviation of the red and green light-emitting layers in a silicon-based OLED display and can increase the guest concentration doping ratio. The device provided by the present invention has high external quantum efficiency and small chromaticity drift. At the same time, the recombination area of ​​carriers can be flexibly controlled by adjusting the mass ratio of n-type host materials and p-type host materials in red light-emitting units and green light-emitting units, and is suitable for industrial applications.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] The present invention provides a red and green OLED device, comprising: a substrate, an anode, an organic functional layer, and a cathode which are stacked in sequence from bottom to top;

[0009] The organic functional layers are stacked in order from bottom to top: a hole injection layer, a hole transport layer, a red and green light emitting layer, an electron transport layer and an electron injection layer;

[0010] The red and green light-emitting layers are stacked in sequence from bottom to top: a red light-emitting unit and a green light-emitting unit;

[0011] The red light emitting unit comprises an n-type red light host material, a p-type red light host material and a red light guest material;

[0012] The green light emitting unit comprises an n-type green light host material, a p-type green light host material and a green light guest material;

[0013] The n-type red light host material and the n-type green light host material independently include carbazole derivatives and / or dibenzofuran derivatives;

[0014] The p-type red light host material and the p-type green light host material are independently triazine derivatives.

[0015] Preferably, the structural formulas of the n-type red light host material and the p-type red light host material are respectively as follows:

[0016] As shown in formula 1 and formula 2:

[0017]

[0018] Preferably, the structural formulas of the n-type green light host material and the p-type green light host material are respectively as follows:

[0019] As shown in formula 3 and formula 4:

[0020]

[0021] Preferably, in the red light emitting unit, the mass ratio of the n-type red light host material to the p-type red light host material is (1-9):(9-1).

[0022] Preferably, in the green light emitting unit, the mass ratio of the n-type green light host material to the p-type green light host material is (1-9):(9-1).

[0023] Preferably, in the red light emitting unit: the red light guest material includes Ir(piq)3; the mass of the red light guest material accounts for 0.1-6% of the total mass of the red light emitting unit.

[0024] Preferably, in the green light emitting unit: the green light guest material includes Ir(ppy)2(acac); the mass of the green light guest material accounts for 1-10% of the total mass of the green light emitting unit.

[0025] Preferably, the thickness of the red light emitting unit is 2 to 20 nm.

[0026] Preferably, the green light emitting unit has a thickness of 2 to 40 nm.

[0027] The present invention provides a white light OLED device, comprising: a substrate, an anode, an organic functional layer, and a cathode which are stacked in sequence from bottom to top;

[0028] The organic functional layers are stacked in order from bottom to top: a first hole injection layer, a first hole transport layer, a red and green light emitting layer, a first electron transport layer, a first electron injection layer, a second hole injection layer, a second hole transport layer, a blue light emitting layer, a second electron transport layer and a second electron injection layer;

[0029] The red and green light-emitting layers are stacked in sequence from bottom to top: a red light-emitting unit and a green light-emitting unit;

[0030] The red light emitting unit comprises an n-type red light host material, a p-type red light host material and a red light guest material;

[0031] The green light emitting unit comprises an n-type green light host material, a p-type green light host material and a green light guest material;

[0032] The n-type red light host material and the n-type green light host material independently include carbazole derivatives and / or dibenzofuran derivatives;

[0033] The p-type red light host material and the p-type green light host material are independently triazine derivatives.

[0034] Preferably, the thickness of the first hole injection layer and the second hole injection layer is 10 nm, the thickness of the first hole transport layer and the second hole transport layer is 40 nm and 45 nm respectively, the thickness of the first electron transport layer and the second electron transport layer is 10 nm and 30 nm respectively; the thickness of the first electron injection layer and the second electron injection layer is 20 nm and 15 nm respectively;

[0035] The anode is indium tin oxide;

[0036] The cathode is indium zinc oxide (IZO).

[0037] The present invention provides a red-green OLED device, comprising: a substrate, an anode, an organic functional layer, and a cathode which are stacked in sequence from bottom to top; the organic functional layers are stacked in sequence from bottom to top: a hole injection layer, a hole transport layer, a red and green light-emitting layer, an electron transport layer, and an electron injection layer; the red and green light-emitting layers are stacked in sequence from bottom to top: a red light-emitting unit and a green light-emitting unit; the red light-emitting unit comprises an n-type red light host material, a p-type red light host material, and a red light guest material; the green light-emitting unit comprises an n-type green light host material, a p-type green light host material, and a green light guest material; the n-type red light host material and the n-type green light host material independently comprise carbazole derivatives and / or dibenzofuran derivatives; the p-type red light host material and the p-type green light host material are triazine derivatives. The red-green OLED device provided by the present invention: the red light emitting unit uses a bipolar dual host material: an n-type red light host material (RH-n) and a p-type red light host material (RH-p); at the same time, the green light emitting unit also uses a bipolar dual host material: an n-type green light host material (GH-n) and a p-type green light host material (GH-p), so that the present invention can adjust the recombination area of ​​the carriers by adjusting the mass ratio of the n-type host material and the p-type host material in the red light emitting unit and the green light emitting unit, so as to achieve the requirements of high efficiency and low color deviation of the device. The present invention is adjusted based on the red light emitting unit and the green light emitting unit, that is, the red and green single-layer structure, and its structure is suitable for the red and green light emitting layers in the white light OLED device. The structure of the embodiment shows that the silicon-based OLED micro display provided by the present invention has high external quantum efficiency and small chromaticity drift, and can flexibly adjust the recombination area of ​​the carriers by adjusting the mass ratio of the n-type host material and the p-type host material in the red light emitting unit and the green light emitting unit, which is suitable for industrial application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the structure of a silicon-based OLED microdisplay white light device;

[0039] Figure 1 Middle: 1 is the first hole injection layer, 2 is the first hole transport layer, 3 is the red-green light-emitting layer (RG-EML), 4 is the first electron transport layer, 5 is the first electron injection layer, 6 is the second hole injection layer, 7 is the second hole transport layer, 8 is the blue light-emitting layer, 9 is the second electron transport layer, and 10 is the second electron injection layer;

[0040] Figure 2 for Figure 1 The energy transfer process of the silicon-based OLED microdisplay of the structure shown;

[0041] Figure 3 A schematic diagram of the structure and materials of the red light emitting unit and the green light emitting unit of the device in which the red light emitting unit and the green light emitting unit are separately arranged;

[0042] Figure 4 for Figure 3 The energy transfer process of the device shown;

[0043] Figure 5 A schematic diagram of the structure and materials of the red light emitting unit and the green light emitting unit of the device provided by the present invention;

[0044] Figure 6 It is the spectrum diagram of the product of comparative example 1 under different voltage conditions;

[0045] Figure 7 It is the spectrum diagram of the product of comparative example 2 under different voltage conditions;

[0046] Figure 8 The spectra of the product of Example 1 under different voltage conditions;

[0047] Fig. 9 This is the spectrum diagram of the product of Example 2 under different voltage conditions. DETAILED DESCRIPTION

[0048] The present invention provides a red and green OLED device, comprising: a substrate, an anode, an organic functional layer, and a cathode which are stacked in sequence from bottom to top;

[0049] The organic functional layers are stacked in order from bottom to top: a hole injection layer, a hole transport layer, a red and green light emitting layer, an electron transport layer and an electron injection layer;

[0050] The red and green light-emitting layers are stacked in sequence from bottom to top: a red light-emitting unit and a green light-emitting unit;

[0051] The red light emitting unit comprises an n-type red light host material, a p-type red light host material and a red light guest material;

[0052] The green light emitting unit comprises an n-type green light host material, a p-type green light host material and a green light guest material;

[0053] The n-type red light host material and the n-type green light host material independently include carbazole derivatives and / or dibenzofuran derivatives;

[0054] The p-type red light host material and the p-type green light host material are independently triazine derivatives.

[0055] In the present invention, unless otherwise specified, all preparation raw materials / components are commercially available products well known to those skilled in the art.

[0056] The red and green OLED device provided by the present invention comprises a substrate. In the present invention, the substrate is preferably a silicon substrate.

[0057] The red and green OLED device provided by the present invention comprises an anode arranged on the substrate. In the present invention, the anode is preferably indium tin oxide (ITO).

[0058] The red and green OLED device provided by the present invention includes an organic functional layer arranged on the anode. In the present invention, the organic functional layer of the red and green OLED device includes: a hole injection layer (HIL), a hole transport layer (HTL), a light-emitting layer, an electron transport layer (ETL), and an electron injection layer (EIL); the organic functional layers are stacked from bottom to top: a hole injection layer, a hole transport layer, a red and green light-emitting layer, an electron transport layer, and an electron injection layer. The red and green light-emitting layers are stacked from bottom to top: a red light-emitting unit and a green light-emitting unit.

[0059] In the present invention, in the organic functional layer of the red and green OLED device: the thickness of the hole injection layer is 10 nm. The material of the hole injection layer is preferably TCTA-doped NDP-9. The thickness of the hole transport layer is preferably 40 nm. The material of the hole transport layer is preferably TCTA. The thickness of the electron transport layer is preferably 30 nm. The material of the electron transport layer is preferably Be(pp)2. The thickness of the electron injection layer is preferably 10 nm. The material of the electron injection layer is preferably Be(pp)2-doped Li single substance.

[0060] In the present invention, in the red and green light-emitting layers of the red and green OLED device: the red light-emitting unit includes an n-type red light host material, a p-type red light host material and a red light guest material. The green light-emitting unit includes an n-type green light host material, a p-type green light host material and a green light guest material. The n-type red light host material and the n-type green light host material independently include carbazole derivatives and / or dibenzofuran derivatives; the p-type red light host material and the p-type green light host material are independently triazine derivatives.

[0061] In a specific embodiment of the present invention, the structural formulas of the n-type red light host material and the p-type red light host material are shown in Formula 1 and Formula 2, respectively:

[0062]

[0063] In a specific embodiment of the present invention, the structural formulas of the n-type green light host material and the p-type green light host material are shown in Formula 3 and Formula 4 respectively:

[0064]

[0065] In a specific embodiment of the present invention, in the red light emitting unit: the mass ratio of the n-type red light host material to the p-type red light host material is preferably (1-9):(9-1), and more preferably 7:3.

[0066] In a specific embodiment of the present invention, in the green light emitting unit, the mass ratio of the n-type green light host material to the p-type green light host material is preferably (1-9):(9-1), and more preferably (3-5):(5-7).

[0067] In a specific embodiment of the present invention, in the red light emitting unit: the red light guest material preferably includes Ir(piq) 3. The mass of the red light guest material preferably accounts for 0.1-6% of the total mass of the red light emitting unit, specifically 2%.

[0068] In a specific embodiment of the present invention, in the green light emitting unit: the green light guest material preferably includes Ir(ppy)2(acac). The mass of the green light guest material preferably accounts for 1-10% of the total mass of the green light emitting unit, specifically 2%.

[0069] In a specific embodiment of the present invention, the thickness of the red light emitting unit is preferably 2-20 nm, specifically 3 nm.

[0070] In a specific embodiment of the present invention, the thickness of the green light emitting unit is preferably 2-40 nm, specifically 20 nm.

[0071] The red and green OLED device provided by the present invention comprises a cathode arranged on the organic functional layer, and the cathode is indium zinc oxide (IZO).

[0072] The present invention provides a method for preparing a red and green OLED device according to the above technical solution, comprising the following steps:

[0073] An anode, an organic functional layer and a cathode are sequentially prepared on the substrate to obtain the red and green OLED device. In the present invention, the anode is preferably prepared by magnetron sputtering. The organic functional layer is preferably prepared by vacuum evaporation. The cathode is preferably prepared by magnetron sputtering.

[0074] The present invention provides a white light OLED device, comprising: a substrate, an anode, an organic functional layer, and a cathode which are stacked in sequence from bottom to top;

[0075] The organic functional layers are stacked in order from bottom to top: a first hole injection layer, a first hole transport layer, a red and green light emitting layer, a first electron transport layer, a first electron injection layer, a second hole injection layer, a second hole transport layer, a blue light emitting layer, a second electron transport layer and a second electron injection layer;

[0076] The red and green light-emitting layers are stacked in sequence from bottom to top: a red light-emitting unit and a green light-emitting unit;

[0077] The red light emitting unit comprises an n-type red light host material, a p-type red light host material and a red light guest material;

[0078] The green light emitting unit comprises an n-type green light host material, a p-type green light host material and a green light guest material;

[0079] The n-type red light host material and the n-type green light host material independently include carbazole derivatives and / or dibenzofuran derivatives;

[0080] The p-type red light host material and the p-type green light host material are independently triazine derivatives.

[0081] The white light OLED device provided by the present invention comprises a substrate. In the present invention, the substrate is preferably a silicon substrate.

[0082] The white light OLED device provided by the present invention comprises an anode arranged on the substrate. In the present invention, the anode is preferably indium tin oxide (ITO).

[0083] The white light OLED device provided by the present invention comprises an organic functional layer arranged on the anode. In the present invention, the organic functional layers of the white light OLED device are stacked in sequence from bottom to top: a first hole injection layer, a first hole transport layer, a red and green light emitting layer, a first electron transport layer, a first electron injection layer, a second hole injection layer, a second hole transport layer, a blue light emitting layer, a second electron transport layer and a second electron injection layer. The red and green light emitting layers are stacked in sequence from bottom to top: a red light emitting unit and a green light emitting unit.

[0084] In the present invention, in the organic functional layer of the white light OLED device: the thickness of the first hole injection layer and the second hole injection layer is 10nm. The material of the first hole injection layer and the second hole injection layer is preferably TCTA-doped NDP-9. The thickness of the first hole transport layer and the second hole transport layer is preferably 40nm and 45nm, respectively. The material of the first hole transport layer and the second hole transport layer is preferably TCTA. The thickness of the first electron transport layer and the second electron transport layer is preferably 10nm and 30nm, respectively. The material of the first electron transport layer and the second electron transport layer is preferably Be(pp)2. The thickness of the first electron injection layer and the second electron injection layer is preferably 20nm and 15nm, respectively. The material of the first electron injection layer and the second electron injection layer is preferably Be(pp)2-doped Li element.

[0085] In the present invention, the blue light emitting layer preferably includes a blue light host material (B-host, BH) and a blue light guest material (B-dopant, BD).

[0086] In a specific embodiment of the present invention, the chemical structural formula of the blue light host material is as follows:

[0087]

[0088] In a specific embodiment of the present invention, the chemical structure of the blue light guest material is as follows:

[0089]

[0090] In a specific embodiment of the present invention, the thickness of the blue light emitting layer is preferably 15 to 30 nm, and more preferably 20 nm, and the doping ratio of the blue light guest material in the blue light emitting layer is preferably 1 to 10%, and more preferably 2%. The doping ratio of the blue light guest material in the blue light emitting layer is the percentage of the blue light guest material in the total mass of the blue light emitting layer.

[0091] In the present invention, in the red and green light-emitting layers in the organic functional layer of the white light OLED device: the red light-emitting unit includes an n-type red light host material, a p-type red light host material and a red light guest material. The green light-emitting unit includes an n-type green light host material, a p-type green light host material and a green light guest material. The n-type red light host material and the n-type green light host material independently include carbazole derivatives and / or dibenzofuran derivatives; the p-type red light host material and the p-type green light host material are triazine derivatives.

[0092] In a specific embodiment of the present invention, the structural formulas of the n-type red light host material and the p-type red light host material are shown in Formula 1 and Formula 2, respectively:

[0093]

[0094] In a specific embodiment of the present invention, the structural formulas of the n-type green light host material and the p-type green light host material are shown in Formula 3 and Formula 4 respectively:

[0095]

[0096] In a specific embodiment of the present invention, in the red light emitting unit: the mass ratio of the n-type red light host material to the p-type red light host material is preferably (1-9):(9-1), and more preferably 7:3.

[0097] In a specific embodiment of the present invention, in the green light emitting unit, the mass ratio of the n-type green light host material to the p-type green light host material is preferably (1-9):(9-1), and more preferably (3-5):(5-7).

[0098] In a specific embodiment of the present invention, in the red light emitting unit: the red light guest material preferably includes Ir(piq) 3. The mass of the red light guest material preferably accounts for 0.1-6% of the total mass of the red light emitting unit, specifically 2%.

[0099] In a specific embodiment of the present invention, in the green light emitting unit: the green light guest material preferably includes Ir(ppy)2(acac). The mass of the green light guest material preferably accounts for 1-10% of the total mass of the green light emitting unit, specifically 2%.

[0100] In a specific embodiment of the present invention, the thickness of the red light emitting unit is preferably 2-20 nm, specifically 3 nm.

[0101] In a specific embodiment of the present invention, the thickness of the green light emitting unit is preferably 2-40 nm, specifically 20 nm.

[0102] The white light OLED device provided by the present invention comprises a cathode arranged on the organic functional layer, and the cathode is indium zinc oxide (IZO).

[0103] The present invention provides a method for preparing the white light OLED device described in the above technical solution, comprising the following steps:

[0104] An anode, an organic functional layer and a cathode are sequentially prepared on the substrate to obtain the white light OLED device. In the present invention, the anode is preferably prepared by magnetron sputtering. The organic functional layer is preferably prepared by vacuum evaporation. The cathode is preferably prepared by magnetron sputtering.

[0105] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0106] Example 1

[0107] The red and green OLED device provided in this embodiment includes: a silicon substrate, an anode, an organic functional layer, and a cathode which are stacked in sequence from bottom to top.

[0108] The anode is formed by magnetron sputtering, the material used is selected from ITO, and the thickness is 10nm.

[0109] The cathode is made of IZO with a thickness of 130 nm.

[0110] The organic functional layer includes a hole injection layer (HIL), a hole transport layer (HTL), a red light emitting unit, a green light emitting unit, an electron transport layer (ETL) and an electron injection layer (EIL), which are deposited in sequence on the anode by thermal evaporation. The material of the hole injection layer is selected from TCTA-doped NDP-9, the doping concentration of TCTA-doped NDP-9 is 0.5%-10%, specifically 2% in this embodiment, and the thickness is 10nm; the hole transport layer is selected from TCTA, with a thickness of 40nm; the electron transport layer is selected from Be(pp)2, with a thickness of 30nm; the electron injection layer material is selected from Be(pp)2-doped Li single substance, with a doping concentration of 0.5%-10%, specifically 1% in this embodiment, and a thickness of 10nm.

[0111] The thickness of the red light emitting unit is 3nm, and the red light emitting unit is composed of an n-type red light host material (RH1), a p-type red light host material (RH2) and a red light guest material; the structural formula of the n-type red light host material is shown in Formula 1, the structural formula of the p-type red light host material is shown in Formula 2, and the red light guest material is Ir(piq)3. The mass of the n-type red light host material accounts for 70% of the total mass of the n-type red light host material and the p-type red light host material. The mass of the p-type red light host material accounts for 30% of the total mass of the n-type red light host material and the p-type red light host material. The mass of the red light guest material accounts for 2% of the total mass of the n-type red light host material, the p-type red light host material and the red light guest material.

[0112] The thickness of the green light emitting unit is 20nm, and the green light emitting unit is composed of an n-type green light host material (GH1), a p-type green light host material (GH2) and a green light guest material; the structural formula of the n-type green light host material is shown in Formula 3, the structural formula of the p-type green light host material is shown in Formula 4, and the green light guest material is Ir(ppy)2(acac). The mass of the n-type green light host material accounts for 50% of the total mass of the n-type green light host material and the p-green-red light host material. The mass of the p-type green light host material accounts for 50% of the total mass of the n-type green light host material and the p-green-red light host material. The mass of the green light guest material accounts for 2% of the total mass of the n-type green light host material, the p-type green light host material and the green light guest material.

[0113] The red and green OLED devices provided in this embodiment are prepared by the following method:

[0114] On the silicon substrate, an anode is formed, and the anode material is selected from ITO with a thickness of 10nm. A hole injection layer and a hole transport layer are sequentially deposited on the anode. The material of the hole injection layer is selected from TCTA-doped NDP-9 with a thickness of 10nm. The hole transport layer is selected from TCTA with a thickness of 40nm. A red light emitting unit and a green light emitting unit are prepared on the hole transport layer. An electron transport layer, an electron injection layer and a cathode are sequentially deposited on the green light emitting unit, wherein the electron transport layer material is selected from Be(pp)2 with a thickness of 30nm; the electron injection layer material is selected from Be(pp)2 doped with Li single substance, with a doping concentration of 0.5%-10%, specifically 1% in this embodiment, and a thickness of 10nm; the cathode is selected from IZO with a thickness of 130nm.

[0115] Example 2

[0116] The structure and preparation method of the red and green OLED devices provided in Example 1 are basically the same, except that:

[0117] The thickness of the green light emitting unit is 20nm, and the green light emitting unit is composed of an n-type green light host material, a p-type green light host material and a green light guest material; the structural formula of the n-type green light host material is shown in Formula 3, the structural formula of the p-type green light host material is shown in Formula 4, and the green light guest material is Ir(ppy)2(acac). The mass of the n-type green light host material accounts for 30% of the total mass of the n-type green light host material and the p-green-red light host material. The mass of the p-type green light host material accounts for 70% of the total mass of the n-type green light host material and the p-green-red light host material. The mass of the green light guest material accounts for 2% of the total mass of the n-type green light host material, the p-type green light host material and the green light guest material.

[0118] Comparative Example 1

[0119] The red and green OLED device provided in this comparative example includes: a silicon substrate, an anode, an organic functional layer, and a cathode which are stacked in sequence from bottom to top.

[0120] The anode is formed by magnetron sputtering, the material used is selected from ITO, and the thickness is 10nm.

[0121] The cathode is made of IZO and has a thickness of 130 nm.

[0122] The organic functional layer includes a hole injection layer (HIL), a hole transport layer (HTL), a red and green light-emitting layer (RG-EML), an electron transport layer (ETL) and an electron injection layer (EIL), which are deposited in sequence on the anode by thermal evaporation. The material of the hole injection layer is selected from TCTA-doped NDP-9, the doping concentration of TCTA-doped NDP-9 is 0.5%-10%, specifically 2% in this comparative example, and the thickness is 10nm; the hole transport layer is selected from TCTA, with a thickness of 40nm; the electron transport layer is selected from Be(pp)2, with a thickness of 30nm; the electron injection layer material is selected from Be(pp)2-doped Li single substance, with a doping concentration of 0.5%-10%, specifically 1% in the actual comparative example, and a thickness of 10nm.

[0123] The thickness of the red and green light emitting layers is 40nm, and the green light emitting layer is composed of a host material, a red light guest material and a green light guest material; the host material is a compound of the structure described in Formula 3; the red light guest material is Ir(piq)3, and the green light guest material is Ir(ppy)2(acac). The mass of the green light guest material accounts for 6% of the total mass of the host material, the red light guest material and the green light guest material. The mass of the red light guest material accounts for 0.3% of the total mass of the host material, the red light guest material and the green light guest material.

[0124] The red and green OLED devices provided in this comparative example are prepared by the following method:

[0125] A magnetron sputtering anode is formed on a silicon substrate, and the anode material is selected from ITO with a thickness of 10. A hole injection layer and a hole transport layer are sequentially deposited on the anode. The material of the hole injection layer is selected from TCTA-doped NDP-9 with a thickness of 10 nm. The hole transport layer is selected from TCTA with a thickness of 40 nm. A green light emitting layer is prepared on the hole transport layer. An electron transport layer, an electron injection layer and a cathode are sequentially deposited on the green light emitting layer, wherein the electron transport layer material is selected from Be(pp)2 with a thickness of 30 nm; the electron injection layer material is selected from Be(pp)2 doped with Li single substance with a thickness of 10 nm; the cathode is selected from IZO with a thickness of 130 nm.

[0126] Comparative Example 2

[0127] The red and green OLED device provided in this comparative example includes: a silicon substrate, an anode, an organic functional layer, and a cathode which are stacked in sequence from bottom to top.

[0128] The anode is formed by magnetron sputtering, the material used is selected from ITO, and the thickness is 10nm.

[0129] The cathode is made of IZO and has a thickness of 130 nm.

[0130] The organic functional layer includes a hole injection layer (HIL), a hole transport layer (HTL), a red light emitting unit, a green light emitting unit, an electron transport layer (ETL) and an electron injection layer (EIL), which are prepared by sequentially depositing on the anode by thermal evaporation. The material of the hole injection layer is selected from TCTA-doped NDP-9, the doping concentration of TCTA-doped NDP-9 is 0.5%-10%, specifically 2% in this comparative example, and the thickness is 10nm; the hole transport layer is selected from TCTA, with a thickness of 40nm; the electron transport layer is selected from Be(pp)2, with a thickness of 30nm; the electron injection layer material is selected from Be(pp)2-doped Li single substance, with a doping concentration of 0.5%-10%, specifically 1% in the actual comparative example, and a thickness of 10nm.

[0131] The thickness of the red light emitting unit is 3 nm, and the red light emitting unit is composed of a red light host material and a red light guest material; the red light host material is a compound of the structure shown in Formula 1, and the red light guest material is Ir(piq)3. The mass of the red light guest material accounts for 2% of the total mass of the red light host material and the red light guest material.

[0132] The thickness of the green light emitting unit is 20nm, and the green light emitting unit is composed of a green light host material and a green light guest material; the green light host material is a compound with a structure shown in Formula 3 and a compound with a structure shown in Formula 4, and the mass ratio of the compound with a structure shown in Formula 3 to the compound with a structure shown in Formula 4 is 1:1, and the green light guest material is Ir(ppy)2(acac). The mass of the green light guest material accounts for 2% of the total mass of the green light host material and the green light guest material.

[0133] The red and green OLED devices provided in this comparative example are prepared by the following method:

[0134] Magnetron sputtering anode on silicon substrate, anode material selected from ITO, thickness of 10nm. On the anode, hole injection layer and hole transport layer are sequentially evaporated. The hole injection layer material is selected from TCTA doped NDP-9, thickness of 10nm. The hole transport layer is selected from TCTA, thickness of 40nm. Red light emitting unit and green light emitting unit are prepared on the hole transport layer. On the green light emitting unit, electron transport layer, electron injection layer and cathode are sequentially evaporated, wherein the electron transport layer material is selected from Be(pp)2, thickness of 30nm; the electron injection layer material is selected from Be(pp)2 doped Li single substance, thickness of 10nm; the cathode is selected from IZO, thickness of 130nm. .

[0135] Test Case

[0136] The performance tests were performed on the red and green OLED devices prepared in Examples 1-2 and Comparative Examples 1-2.

[0137] Comparative Example 1:

[0138] Substrate / ITO / HIL(10) / HTL(40) / GH:GD(40,6%,0.3%) / ETL(30) / EIL(10) / IZO;

[0139] Comparative Example 2:

[0140] Substrate / ITO / HIL(10) / HTL(40) / RH:RD(3,2%) / GH1:GH2:GD(20,49%,49%,2%) / ETL(30) / EIL(10) / IZO(130);

[0141] Embodiment 1~2:

[0142] Substrate / ITO / HIL(10) / HTL(40) / RH:RD(3,2%) / GH:GD(20,2%) / ETL(30) / EIL(10) / IZO(130nm).

[0143] Figure 6 It is the spectrum diagram of the product of comparative example 1 under different voltage conditions; Figure 7 It is the spectrum diagram of the product of comparative example 2 under different voltage conditions; Figure 8 The spectra of the product of Example 1 under different voltage conditions; Fig. 9 This is the spectrum diagram of Example 2 under different voltage conditions.

[0144] From the comparison data of the spectra of comparative example 1 and embodiment 1, it can be seen that the device in embodiment 1 uses the color coordinates adjusted by the bipolar red and green light main body, and its chromaticity drift is significantly smaller than the red and green co-doped structure in comparative example 1.

[0145] From the spectral data of Example 1 and Example 2, the present invention can adjust the relative intensity of the red and green spectra by the n / p doping ratio of the host.

[0146] The VL test data results of the silicon-based OLED microdisplays prepared in Examples 1-2 and Comparative Examples 1-2 are shown in Table 1.

[0147] Table 1 VL test data results of silicon-based OLED microdisplays prepared in Examples 1-2 and Comparative Examples 1-2

[0148] NO. Comparative Example 1 Comparative Example 2 Example 1 Example 2 V(V) 2.81 3.1 2.9 3.05 <![CDATA[J(mA / cm 2 )]]> 2.02 2.81 1.86 1.7 <![CDATA[L(cd / m 2 )]]> 1000 1000 1000 1000 CE(cd / A) 49.5 35.59 53.76 58.82 PE(lm / W) 55.32 36.05 58.21 60.56 EQE(%) 20.4 9.9 22.31 23.62 CIEx 0.453 0.315 0.451 0.4739 CIE 0.527 0.64 0.534 0.512

[0149] It can be seen from the data in Table 1 that compared with the red-green co-doped structure device in Comparative Example 1, the structure device in Comparative Example 2 uses a red light host doped with a red light guest, and a green light host doped with a green light guest, under the condition of the same color coordinates, the external quantum efficiency of the device is improved by about 10%.

[0150] It can be found from Comparative Example 2 and Examples 1 and 2 that the color point of the device can be adjusted by adjusting the doping ratio of the RH & GH hosts.

[0151] It can be seen from the above embodiments that in the red and green OLED device provided by the present invention: the red light emitting unit uses a bipolar dual host material: an n-type red light host material (RH-n) and a p-type red light host material (RH-p); at the same time, the green light emitting unit also uses a bipolar dual host material: an n-type green light host material (GH-n) and a p-type green light host material (GH-p), so that the present invention can adjust the recombination area of ​​the carriers by adjusting the mass ratio of the n-type host material and the p-type host material in the red light emitting unit and the green light emitting unit to achieve the high efficiency and low color deviation requirements of the device. The present invention is based on the red light emitting unit and the green light emitting unit, that is, the red and green single-layer structure, and its structure is suitable for the red and green light emitting layers (laminated white light structure) in the laminated white light structure. The structure of the embodiment shows that the silicon-based OLED micro display provided by the present invention has high external quantum efficiency and small chromaticity drift, and can flexibly adjust the recombination area of ​​the carriers by adjusting the mass ratio of the n-type host material and the p-type host material in the red light emitting unit and the green light emitting unit, which is suitable for industrial application.

[0152] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A red and green OLED device, characterized in that: include: A substrate, an anode, an organic functional layer, and a cathode are stacked in sequence from bottom to top; The organic functional layers are stacked in order from bottom to top: a hole injection layer, a hole transport layer, a red and green light emitting layer, an electron transport layer and an electron injection layer; The red and green light-emitting layers are stacked in sequence from bottom to top: a red light-emitting unit and a green light-emitting unit; The red light emitting unit comprises an n-type red light host material, a p-type red light host material and a red light guest material; The green light emitting unit comprises an n-type green light host material, a p-type green light host material and a green light guest material; The n-type red light host material and the n-type green light host material independently include carbazole derivatives and / or dibenzofuran derivatives; The p-type red light host material and the p-type green light host material are independently triazine derivatives.

2. The red-green OLED device according to claim 1, characterized in that: The structural formulas of the n-type red light host material and the p-type red light host material are shown in Formula 1 and Formula 2, respectively:

3. The red-green OLED device according to claim 1, characterized in that: The structural formulas of the n-type green light host material and the p-type green light host material are shown in Formula 3 and Formula 4 respectively:

4. The red-green OLED device according to claim 1 or 2, characterized in that: In the red light emitting unit, the mass ratio of the n-type red light host material to the p-type red light host material is (1-9):(9-1).

5. The red-green OLED device according to claim 1 or 3, characterized in that: In the green light emitting unit, the mass ratio of the n-type green light host material to the p-type green light host material is (1-9): (9-1).

6. The red-green OLED device according to claim 1 or 2, characterized in that: In the red light emitting unit: the red light guest material is Ir(piq)3; the mass of the red light guest material accounts for 0.1-6% of the total mass of the red light emitting unit.

7. The red-green OLED device according to claim 1 or 3, characterized in that: In the green light emitting unit: the green light guest material is Ir(ppy)2(acac); the mass of the green light guest material accounts for 1-10% of the total mass of the green light emitting unit.

8. The red-green OLED device according to claim 1, characterized in that: The thickness of the red light emitting unit is 2-20 nm.

9. The red-green OLED device according to claim 1, characterized in that: The thickness of the green light emitting unit is 2-40 nm.

10. A white light OLED device, characterized in that: include: A substrate, an anode, an organic functional layer, and a cathode are stacked in sequence from bottom to top; The organic functional layers are stacked in order from bottom to top: a first hole injection layer, a first hole transport layer, a red and green light emitting layer, a first electron transport layer, a first electron injection layer, a second hole injection layer, a second hole transport layer, a blue light emitting layer, a second electron transport layer and a second electron injection layer; The red and green light-emitting layers are stacked in sequence from bottom to top: a red light-emitting unit and a green light-emitting unit; The red light emitting unit comprises an n-type red light host material, a p-type red light host material and a red light guest material; The green light emitting unit comprises an n-type green light host material, a p-type green light host material and a green light guest material; The n-type red light host material and the n-type green light host material independently include carbazole derivatives and / or dibenzofuran derivatives; The p-type red light host material and the p-type green light host material are independently triazine derivatives.

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