Light-Emitting Element Electron-Relay Layer Low Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current light-emitting elements with multiple layers require high voltage for operation due to interface interactions between metal-doped layers and charge-generation layers, leading to increased power consumption and reduced luminance.
Innovation Solution
A light-emitting element structure with a charge production region, electron-relay layer, and electron-injecting buffer is implemented, where the electron-relay layer prevents interaction between the charge production and electron-injecting layers, allowing efficient electron injection and reducing the driving voltage, using materials with specific LUMO levels to minimize electric field and enhance electron injection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a charge production layer formed of vanadium pentoxide is provided over a metal-doped layer, then a light-emitting element with multiple light-emitting units can be constructed, but the interface between the metal-doped layer and the charge-generation layer has a high electric field requiring high voltage for driving
Solution Approach 1:
An electron-relay layer is introduced as an intermediary between the charge production layer and the electron-injecting buffer. This intermediate layer mediates electron transport, reducing the electric field intensity at the charge production layer interface while maintaining efficient electron injection into the light-emitting layer, thereby enabling low-voltage operation
Solution Approach 2:
The patent changes the LUMO level parameter of the electron-relay layer to be between that of the charge production layer and the light-emitting layer. This parameter optimization creates favorable electron transport conditions, reducing the energy barrier and enabling efficient electron injection at lower voltages
2Illumination intensity
If a large amount of current is supplied to the light-emitting layer, then emission luminance can be increased, but power consumption increases and deterioration of the light-emitting element is accelerated
Solution Approach 1:
The electron-relay layer acts as a mediator that improves electron injection efficiency into the light-emitting layer. This enables achieving high emission luminance through efficient electron transport rather than high current density, thereby reducing power consumption and preventing element deterioration
Solution Approach 2:
By optimizing the LUMO level parameter of the electron-relay layer, the patent creates favorable conditions for electron injection. This parameter change enables high luminance output at lower current densities, reducing power consumption and extending device lifetime
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enables a light-emitting element that can be driven at low voltage while maintaining high luminance and reducing power consumption, suitable for use in various electronic and lighting devices.
Implementation Method 1
an electron-relay layer which prevents interaction between the charge production region and the electron-injecting buffer, allows efficient electron injection
Implementation Method 2
Current is applied to a light-emitting layer provided between a pair of electrodes in a light-emitting element to excite a light-emitting material contained in the light-emitting layer, whereby a predetermined emission color can be obtained
Data Source
Figure 1A~1B
Figure 2A~2B
Figure 3A~3B
AI summary
An object is to provide a light-emitting element which exhibits light emission with high luminance and can be driven at low voltage. Another object is to provide a light-emitting device or an electronic device with reduced power consumption. Between an anode and a cathode, n (n is a natural number of two or more) EL layers are provided, where between a first EL layer and a second EL layer, a first layer containing any of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth metal compound, and a rare earth metal compound, a second layer containing a material having a high electron-transporting property in contact with the first layer, and a region containing a material having a high hole-transporting property and an acceptor material in contact with the second layer are provided in this order from the anode side.