Multi-Insulator Quantum Dot Coating for Moisture and Oxygen Resistance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Quantum dots in lighting and display devices are vulnerable to water vapor and oxygen, leading to a short lifespan due to environmental degradation, and existing coatings are insufficient in providing comprehensive protection.

Innovation Solution

A semiconductor structure is fabricated with a nanocrystalline core and shell surrounded by multiple insulating layers, particularly silica, which creates a tortuous path for environmental degradants, enhancing the stability and longevity of quantum dots by interrupting defect pathways and providing thermal and humidity resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple insulator coatings are applied to quantum dots, then environmental protection is enhanced by interrupting defect pathways, but the manufacturing process becomes more complex

Engineering Contradiction:
Improveenvironmental protectionVSAvoidmanufacturing process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies base treatment (such as plasma treatment, chemical treatment, or thermal treatment) between the formation of each insulator coating layer. This preliminary action prepares the surface of the previously formed layer to ensure proper adhesion and continuity of the next layer, preventing defects and ensuring high-quality interfaces without requiring complex post-processing steps.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The sequential coating process with base treatment in between allows each layer to self-organize and bond to the previous layer, creating a integrated multi-layer structure. The base treatment activates the surface to naturally accept the next layer, reducing the need for additional complex bonding or assembly operations.

Inventive Principle:
Principle #25Self-service

2Reliability

If thicker insulator coating is applied to quantum dots, then protection from environmental degradation improves, but quantum dot self-quenching increases due to increased distance between dots

Engineering Contradiction:
Improveprotection from environmental degradationVSAvoidquantum dot self-quenching
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The patent segments a potentially thick insulator coating (greater than 20 nm) into multiple thinner layers (each 1-10 nm). This segmentation maintains adequate spacing between quantum dots to prevent self-quenching while still providing comprehensive environmental protection, as the cumulative thickness of multiple thin layers exceeds 20 nm but is distributed in a way that minimizes energy loss.

Inventive Principle:
Principle #1Segmentation

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 multi-layer insulating structure significantly extends the operational life of quantum dots by preventing self-quenching and environmental damage, ensuring high thermal stability and reliability in LED and other applications.

Implementation Method 1

Multiple insulating layers are then formed, encapsulating the quantum dot... creates a tortuous path for environmental degradants, thereby increasing the lifetime of the quantum dot

Methodology Applied
Scientific EffectDiffusion barrier: Diffusion Barrier

Implementation Method 2

The insulator layer comprises a silica layer... providing thermal and humidity resistance

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP3294834B1Composition of, and method for forming, a semiconductor structure with multiple insulator coatings
Publication Date: 2023.11.22 OSRAM OPTO SEMICON GMBH & CO OHG
  • EP3294834B1 patent drawingFigure 1~2A
  • EP3294834B1 patent drawingFigure 2B
  • EP3294834B1 patent drawingFigure 2C

AI summary

Fabricating a semiconductor structure including forming a nanocrystalline core from a first semiconductor material, forming a nanocrystalline shell from a second, different, semiconductor material that at least partially surrounds the nanocrystalline core, wherein the nanocrystalline core and the nanocrystalline shell form a quantum dot. Fabrication further involves forming an insulator layer encapsulating the quantum dot to create a coated quantum dot, and forming an additional insulator layer on the coated quantum.