OLED Electron Transport Layer Using Lithium Quinolate Composite

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional OLEDs with a single organic material electron transport layer require high driving voltage and consume large current, resulting in poor luminous efficiency and insufficient lifespan.

Innovation Solution

An improved electron transport layer (ETL) is formed using an organic metal complex containing alkali metals like lithium or sodium quinolate, co-deposited with a specific compound, which reduces driving voltage and current consumption, and enhances electron transport efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a single organic material is used for the electron transport layer (ETL), then the manufacturing process is simple, but the OLED requires high driving voltage and consumes large current, resulting in poor luminous efficiency and insufficient lifespan

Engineering Contradiction:
Improvesimplicity of ETL manufacturingVSAvoidlifespan and luminous efficiency of OLED
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent uses a composite ETL formed by co-depositing an organic metal complex (containing lithium or sodium quinolate) with a specific organic compound (Formula 1). This composite structure combines the electron transport capabilities of the organic compound with the electron injection properties of the alkali metal complex, achieving both low driving voltage and high reliability without complicating the manufacturing process.

Inventive Principle:
Principle #40Composite materials

2Device complexity

If a single organic material is used for the electron transport layer (ETL), then the device structure is simple, but the driving voltage is high and current consumption is large

Engineering Contradiction:
Improvestructure of electron transport layerVSAvoidcurrent consumption and driving voltage
Core Design Contradiction:
Device complexityVSUse of energy by moving object

Solution Approach 1:

The patent employs a composite material system where an organic metal complex (lithium or sodium quinolate) is combined with a specific organic compound (Formula 1). The alkali metal complex provides excellent electron injection properties that reduce driving voltage, while the organic compound maintains structural simplicity. This composite approach lowers energy consumption without increasing device complexity.

Inventive Principle:
Principle #40Composite materials

3Reliability

If an additional electron injection layer is added to improve electron transport, then the luminous efficiency and lifespan improve, but the device complexity and manufacturing steps increase

Engineering Contradiction:
Improvelifespan and luminous efficiencyVSAvoidnumber of layers in organic structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the functions of the electron injection layer and the electron transport layer into a single composite ETL. By incorporating an organic metal complex (lithium or sodium quinolate) directly into the ETL formulation, the layer simultaneously provides electron injection capability (typically requiring a separate layer) and electron transport function, thereby improving reliability without increasing device complexity or manufacturing steps.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The composite ETL material performs multiple functions: it acts as both an electron injection layer and an electron transport layer. The organic metal complex component provides electron injection from the cathode, while the organic compound component ensures efficient electron transport to the emission layer, eliminating the need for separate functional layers.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP2083459B1Organic light emitting diode and method of manufacturing the same
Publication Date: 2014.08.13 SAMSUNG DISPLAY CO LTD
  • EP2083459B1 patent drawingFigure 1
  • EP2083459B1 patent drawingFigure 2
  • EP2083459B1 patent drawing

AI summary

The invention is directed to organic light emitting diodes (OLEDs) and methods of manufacturing the same. According to embodiments of the invention, an improved electron transport layer (ETL) reduces the driving voltage and current consumption of the OLED, and increase luminous efficiency and lifespan. The OLED includes a first electrode 110, an organic layer 120 on the first electrode and including an emission layer (EML) 121 and an ETL 122, and a second electrode 130 on the organic layer 120.