Blue-Absorbing Photosensitive Resin for High-Resolution Micro-LED Patterning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for forming micro-LED displays using quantum dots for color conversion struggle with blue light transmission through cured photoresist films, leading to degraded display clarity due to insufficient blue light absorption and unnecessary blue light emission.
Innovation Solution
A photosensitive resin composition comprising an acrylic resin with a (meth)acryloyl group in a side chain, a dye with a maximum absorption wavelength between 490 to 430 nm, an oxime-based photo-radical generator, a surfactant, and a solvent, which forms a film that effectively absorbs blue LED light transmitted through cured photoresist films containing quantum dots.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If transmittance at the exposure wavelength is ensured for forming the pattern, then lithography resolution is improved, but blue light transmission increases causing degraded display clarity
Solution Approach 1:
The patent segments the photoresist film into two distinct layers: a lower photoresist layer containing quantum dots for color conversion, and an upper photoresist layer containing a blue light-absorbing dye. This segmentation allows each layer to perform its specific function independently - the lower layer enables lithography patterning while the upper layer selectively absorbs transmitted blue light, thereby resolving the contradiction between maintaining lithography resolution and preventing blue light transmission.
Solution Approach 2:
The patent applies local quality by giving different optical properties to different regions of the photoresist structure. The upper photoresist layer is specifically formulated with a blue light-absorbing dye that has maximum absorption in the blue region (430-490 nm), while the lower layer maintains high transmittance for lithography exposure. This localized functional differentiation allows the structure to simultaneously achieve good lithography resolution and selective blue light absorption.
2Object-affected harmful factors
If a blue light-absorption layer is laminated on cured photoresist films containing quantum dots, then blue light absorption is improved, but the layer cannot be selectively formed only on subpixels requiring color conversion
Solution Approach 1:
The patent merges the blue light-absorbing function with the photoresist material itself by incorporating a blue light-absorbing dye into the upper photoresist layer. This allows the blue light absorption capability to be integrated into the lithography process rather than requiring a separate post-processing step. The dye-containing photoresist can be selectively applied only to subpixels requiring color conversion, enabling both selective formation and effective blue light absorption.
Solution Approach 2:
The patent performs preliminary action by incorporating the blue light-absorbing dye into the photoresist formulation before the lithography process. This allows the blue light absorption property to be built into the material itself, so that when the photoresist is applied and cured, it already possesses both the lithography functionality and the blue light absorption capability, eliminating the need for subsequent separate layer addition.
3Use of energy by moving object
If quantum dots with high absorbance at exposure wavelength are used, then color conversion efficiency is improved, but more blue light is absorbed during lithography exposing the pattern
Solution Approach 1:
The patent segments the photoresist structure into two layers with different functional characteristics. The lower photoresist layer contains quantum dots optimized for color conversion with high absorbance at the exposure wavelength, while the upper photoresist layer contains a blue light-absorbing dye. This segmentation allows the quantum dots to efficiently absorb exposure light for color conversion without the entire structure excessively absorbing blue light, as the upper layer's dye is specifically targeted at absorbing transmitted blue light after it passes through the quantum dot layer.
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 composition enables high lithography resolution and selective absorption of blue light, allowing for efficient transmission of red or green light, thereby enhancing display clarity in micro-LED displays.
Implementation Method 1
an oxime-based photo-radical generator
Implementation Method 2
an acrylic resin having a (meth)acryloyl group in a side chain
Implementation Method 3
a dye having a maximum absorption wavelength at any wavelength of 490 to 430 nm
Data Source
AI summary
The present invention is a photosensitive resin composition for absorbing blue LED light that has been transmitted through a cured photoresist film containing quantum dots capable of emitting red or green fluorescence, the composition containing: (A) an acrylic resin having a (meth)acryloyl group in a side chain; (B) a dye having a maximum absorption wavelength at any wavelength of 490 to 430 nm; (C) an oxime-based photo-radical generator; (D) a surfactant; and (E) a solvent. This can provide: a photosensitive resin composition capable of easily forming a film having high lithography resolution and favorable blue light absorption property; a photosensitive resin film and a photosensitive dry film obtained by using the photosensitive resin composition; patterning processes using these; and displays obtained by using the photosensitive resin composition.