OLED Panel Inorganic Overhangs for Particle-Free Pixel Patterning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current OLED pixel patterning processes leave behind organic material particles that disrupt performance and limit pixel resolution and panel size, necessitating improved methods for sub-pixel circuit formation.
Innovation Solution
The use of inorganic overhang structures in sub-pixel circuits, combined with evaporation deposition, allows for the deposition of OLED material and cathode without contacting lower portions, and the encapsulation layer extends under these structures, eliminating the need for a lift-off process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If photo lithography is used to pattern pixels, then pixel resolution can be improved, but organic material particles are left behind that disrupt OLED performance
Solution Approach 1:
The patent extracts and removes the problematic organic material particles from the pixel patterning process by using a lift-off technique where a sacrificial layer is deposited, patterned, and then removed along with the organic material, leaving only the desired inorganic pixel structures without particle contamination
Solution Approach 2:
The patent introduces a sacrificial layer as an intermediary material that facilitates the patterning process. This sacrificial layer is deposited, patterned using photo lithography, and then removed to take the organic material particles with it, serving as a mediator that enables high-resolution patterning while eliminating the harmful organic residue
2Area of stationary object
If fine metal mask is used for pixel patterning, then panel size can be reduced, but pixel resolution and substrate size are restricted
Solution Approach 1:
The patent replaces the mechanical fine metal mask system with a deposition-based patterning approach using a sacrificial layer. Instead of using physical masks that limit substrate size and resolution, the invention uses vapor deposition techniques to create patterns through material deposition and selective removal, enabling larger panels with higher pixel resolution
3Object-generated harmful factors
If lift-off process is used to remove organic material, then particle issues are eliminated, but manufacturing complexity and time increase
Solution Approach 1:
The patent merges the patterning and material removal steps into a single integrated lift-off process. The sacrificial layer is patterned and then removed together with the organic material in one step, combining what would otherwise be separate operations into a unified process that reduces manufacturing complexity while eliminating particle issues
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
This method enhances pixel-per-inch density and improves OLED performance by preventing particle disruption and increasing throughput without the need for lift-off procedures.
Implementation Method 1
depositing the OLED material using evaporation deposition over a substrate
Implementation Method 2
depositing the OLED material using evaporation deposition
Data Source
AI summary
Embodiments described herein relate to sub-pixel circuits and methods of forming sub-pixel circuits that may be utilized in a display such as an organic light-emitting diode (OLED) display. The device includes a plurality of sub-pixels, each sub-pixel of the plurality of sub-pixels defined by adjacent pixel-defining layer (PDL) structures with inorganic overhang structures disposed on the PDL structures, each sub-pixel having an anode, organic light-emitting diode (OLED) material disposed on the anode, and a cathode disposed on the OLED material. The device is made by a process including the steps of: depositing the OLED material and the cathode by evaporation deposition, and depositing an encapsulation layer disposed over the cathode.