Matrix-Free Quantum Dot Output Coupling Element for Red and IR Light
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing output coupling elements for optoelectronic components face challenges in efficiently decoupling light due to large refractive index differences at semiconductor chip interfaces, particularly for red and IR wavelength ranges, and current nanocomposites like zirconium oxide or titanium dioxide have limitations such as being applicable only as thin films and degrading under blue light or temperature.
Innovation Solution
A method involving the use of quantum dots with semiconductor cores, such as gallium phosphide or indium phosphide, is employed to create a matrix-free output coupling element. These quantum dots are suspended in a medium, applied directly to the component, and the medium is removed, resulting in a transparent, high refractive index element suitable for red and IR radiation decoupling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If nanoparticles such as zirconium oxide or titanium dioxide are used as highly refractive additives for decoupling materials, then the refractive index is increased, but the material can only be applied as thin film and cannot be formed as lenses
Solution Approach 1:
The patent changes the physical state parameter of the decoupling material from a solid nanoparticle suspension to an organic liquid crystal composition. This parameter change enables the material to be applied in thick layers and formed into lens shapes while maintaining high refractive index properties, resolving the contradiction between achieving high refractive index and forming functional optical elements like lenses
Solution Approach 2:
The patent creates a composite material system by combining organic liquid crystal molecules with high refractive index nanoparticles (such as titanium dioxide or zirconium oxide). This composite approach allows the material to simultaneously achieve high refractive index from the nanoparticles and lens-forming capability from the liquid crystal matrix, resolving the technical contradiction
2Illumination intensity
If organically loaded zirconium oxide nanoparticles are used, then refractive index is enhanced, but the material turns yellow under blue light and temperature tests
Solution Approach 1:
The patent changes the chemical composition parameter by using purely inorganic liquid crystal materials instead of organic compounds. This parameter change eliminates the yellowing issue under blue light and temperature exposure while maintaining the high refractive index properties, thus resolving the contradiction between achieving high refractive index and maintaining color stability
Solution Approach 2:
The patent develops a composite material system combining inorganic liquid crystal molecules with high refractive index nanoparticles. This inorganic-inorganic composite approach provides both the high refractive index from the nanoparticles and the color stability from the inorganic liquid crystal matrix, resolving the technical contradiction
3Reliability
If matrix material such as silicone or epoxy is used to embed semiconductor chips, then environmental protection is improved, but light decoupling efficiency decreases due to refractive index differences
Solution Approach 1:
The patent replaces conventional organic matrix materials with a composite material system consisting of inorganic liquid crystal molecules and high refractive index nanoparticles. This composite material provides both environmental protection functions and superior light decoupling efficiency through its high refractive index, resolving the contradiction between reliability and illumination efficiency
Solution Approach 2:
The patent changes the refractive index parameter of the embedding material from 1.4-1.55 (conventional organics) to above 1.6 (inorganic liquid crystal with nanoparticles). This parameter change enables the material to simultaneously provide environmental protection and improved light decoupling efficiency, resolving the technical contradiction
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 method produces a highly efficient, matrix-free output coupling element that enhances light decoupling from semiconductor chips, maintaining transparency and refractive index properties, thus improving the performance of optoelectronic components like light-emitting diodes.
Implementation Method 1
providing quantum dots 2 with a core 3 having a semiconductor material
Implementation Method 2
The quantum dots are in particular transparent to radiation of the red and/or IR wavelength range
Implementation Method 3
producing a suspension 4 having the quantum dots 2 in a suspension medium 5
Implementation Method 4
removing the suspension medium 5 to produce the output coupling element 1
Implementation Method 5
Embodiments provide a significant increase in the refractive index by using, for example, gallium phosphide with a refractive index of 3.314 at 633 nm or indium phosphide with a refractive index of 3.536 at 633 nm
Data Source
AI summary
A method for producing an output coupling element and an output coupling element are disclosed. In an embodiment a method includes producing a suspension having quantum dots in a suspension medium, wherein each quantum dot comprises a core having a semiconductor material, directly applying the suspension onto a surface of an optoelectronic component and/or onto a surface of a carrier and removing the suspension medium for producing the output coupling element, wherein the output coupling element is matrix-free and transparent to radiation of a red range and/or a IR range.