White light electroluminescent device

An electroluminescent device and electroluminescent technology, which are applied in electric solid devices, luminescent materials, electrical components, etc., can solve the problems of poor life and stability of blue light materials, restrict blue light emission, and reduce device life, etc. Energy transfer efficiency, the effect of improving luminous efficiency

Inactive Publication Date: 2012-10-17
OCEANS KING LIGHTING SCI&TECH CO LTD +1
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  • Abstract
  • Description
  • Claims
  • Application Information

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Problems solved by technology

[0004] Luminescent materials are the most important factor affecting luminous efficiency. Luminescent materials can be divided into fluorescent materials (ie, blue light materials) and phosphorescent materials (ie, red light phosphorescent materials and / or green light phosphorescent materials). Fluorescent materials are blocked due to triplet transitions. Therefore, it can only emit light through the radiation inactivation of the singlet state, and the ratio of the triplet excitons to the singlet excitons is about 3:1; and since only 25wt% of the excitons in the fluorescent material can be effectively used, the remaining 75wt % are all through non-radiative attenuation, the energy is released in the form of heat, which increases the temperature of the device, thereby reducing the life of the device, while the phosphorescent material is due to the strong spin coupling effect of the metal atom itself, so the original impossible three-line Therefore, the luminous efficiency is greatly improved. At present, the luminous efficiency of green phosphorescent materials and red phosphorescent materials is relatively good, and the material stability is high, while the life and stability of blue phosphorescent materials are not very good, which restricts blue light glow

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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0041] A white electroluminescent device, its layered structure is as follows:

[0042] Glass / ITO / MoO 3 / NPB / TAPC / Bepp 2 : BCzVBi / Bepp 2 / Bepp 2 : Ir(ppy) 3 : Ir(MDQ) 2 (acac) / Bepp 2 / Bepp 2 : BCzVBi / TPBi / Bphen / Bphen: CsN 3 / Al.

[0043] First, the ITO glass is subjected to photolithography treatment and cut into the required light-emitting area, and then sonicated with detergent, deionized water, acetone, ethanol, and isopropanol for 15 minutes each to remove organic contaminants on the surface of the glass. It is treated with oxygen plasma, the treatment time is 5-15min, and the power is 50W; then, each organic functional layer is sequentially vapor-deposited on the ITO conductive layer to obtain a white photoluminescence device; among them,

[0044] The material of the hole injection layer is MoO 3 , The thickness is 5nm;

[0045] The material of the hole transport layer is NPB with a thickness of 10nm;

[0046] The material of the electron blocking layer is TAPC, and the thickness ...

Embodiment 2

[0061] A white photoluminescence device, its layered structure is: glass / ITO / WO 3 / TPD / TAPC / BeqQ 2 : TBPe / BeqQ 2 / BeqQ 2 : Ir(ppy) 3 : Ir(MDQ) 2 (acac) / BeqQ 2 / BeqQ 2 : TBPe / Alq 3 / BND / Cs 2 CO 3 / Ag.

[0062] First, the ITO glass is subjected to photolithography treatment and cut into the required light-emitting area, and then sonicated with detergent, deionized water, acetone, ethanol, and isopropanol for 15 minutes each to remove organic contaminants on the surface of the glass. It is treated with oxygen plasma, the treatment time is 10min, and the power is 50W; then, each organic functional layer is sequentially vapor-deposited on the ITO conductive layer to obtain a white photoluminescence device; among them,

[0063] The material of the hole injection layer is WO 3 , The thickness is 10nm;

[0064] The material of the hole transport layer is TPD with a thickness of 5nm;

[0065] The material of the electron blocking layer is TAPC, and the thickness is 20nm;

[0066] The blue mater...

Embodiment 3

[0076] A white electroluminescent device, its layered structure is in order: glass / ITO / VO x / TCTA / NPB / BeqQ 2 : DPAVBi / BeqQ 2 / BeqQ 2 : Ir(ppy) 2 (acac)): Ir(piq) 2 (acac) / BeqQ 2 / BeqQ 2 : DPAVBi / BND / TAZ / CsN 3 / Ag-Mg.

[0077] First, the ITO glass is subjected to photolithography treatment and cut into the required light-emitting area, and then sonicated with detergent, deionized water, acetone, ethanol, and isopropanol for 15 minutes each to remove organic contaminants on the surface of the glass. It was treated with oxygen plasma, the treatment time was 15min, and the power was 50W; then, each organic functional layer was vapor-deposited on the ITO conductive layer to obtain a white photoluminescence device; among them,

[0078] The material of the hole injection layer is VO x , The thickness is 40nm;

[0079] The material of the hole transport layer is TCTA with a thickness of 80nm;

[0080] The material of the electron blocking layer is NPB, and the thickness is 60nm;

[0081] The b...

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Abstract

The invention pertains to the field of optoelectronic devices, and discloses a white light electroluminescent device. The device has a layered structure. The layered structure sequentially includes: a base/an electrical conductive layer/a hole injection layer/a hole transporting layer/an electron barrier layer/a first blue light emitting layer/a first spacer layer/a phosphor light emitting layer/a second spacer layer/a second blue light emitting layer/a hole barrier layer/an electron transporting layer/an electron injection layer/a cathode layer. The materials of the first blue light emitting layer and the second blue light emitting layer both are a beryllium complexe material doped with a blue light emitting material, and the material of the phosphor light emitting layer is a beryllium complexe material doped with a red phosphor light emitting material and a green phosphor light emitting material. The white light electroluminescent device of the invention includes a mixed light emitting layer prepared by the blue light emitting layers and the phosphor light emitting layer, and the spacer layers are inserted between the blue light emitting layers and the phosphor light emitting layer, so triplet excitons of the blue light emitting material can be diffused into the red phosphor light emitting material and the green phosphor light emitting material to undergo radiative transition so as to emit light, so that light emitting efficiency of the device is further improved.

Description

Technical field [0001] The invention relates to the field of optoelectronic devices, in particular to a white electroluminescent device. Background technique [0002] In 1987, C.W.Tang and Van Slyke of Eastman Kodak Company in the United States reported a breakthrough in organic electroluminescence research. Using ultra-thin film technology, a high-brightness, high-efficiency double-layer organic electroluminescent device (OLED) was fabricated. In this double-layer structured device, the brightness reaches 1000cd / m at 10V 2 , Its luminous efficiency is 1.51lm / W, and its lifetime is more than 100 hours. [0003] The light-emitting principle of OLED is based on the fact that electrons are injected from the cathode to the lowest unoccupied molecular orbital (LUMO) of organic matter under the action of an external electric field, and holes are injected from the anode to the highest occupied orbital (HOMO) of organic matter. Electrons and holes meet and recombine in the light-emitting...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H01L51/50H01L51/52H01L51/54C09K11/06
CPCY02B20/181Y02B20/00
Inventor 周明杰王平黄辉陈吉星
Owner OCEANS KING LIGHTING SCI&TECH CO LTD
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