Perovskite Light-Emitting Layer Patterning Without Banks

Solution Overview

Problem

The production of full-color perovskite electroluminescent displays (PeLEDs) faces challenges in achieving high uniformity and reproducibility due to the need for containment structures that reduce the emissive area and increase costs, as current methods require large containment structures to prevent ink spreading, which negatively impact layer thickness uniformity and fabrication speed.

Innovation Solution

A method involving the formation of metal halide perovskite light-emitting layers by depositing charge injecting and conducting materials, followed by halide conversion steps using benzoyl halide solutions or gases to create patterns of different halide perovskites (bromide, iodide, and chloride) without the need for banks, allowing for precise control of emission wavelengths and maintaining crystalline structure integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If large containment structures (banks) are used to prevent ink spreading, then pattern formation reliability is improved, but emissive area is reduced and manufacturing cost increases

Engineering Contradiction:

Improvepattern formation reliabilityVSAvoidemissive area

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The patent removes the containment structure (bank) from the system entirely. Instead of using physical barriers to prevent ink spreading, the invention relies on self-aligned patterning through sequential deposition and photolithographic etching, where the pattern is defined by the mask and etching process rather than by containment walls.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent divides the patterning process into multiple sequential steps: first depositing the perovskite layer, then applying a photomask, performing photolithographic etching to define the pattern, and finally removing the mask. This segmentation allows precise pattern formation without requiring physical containment structures.

Inventive Principle:

Principle #1Segmentation

2Reliability

If large containment structures (banks) are used to prevent ink spreading, then pattern formation reliability is improved, but manufacturing cost increases

Engineering Contradiction:

Improvepattern formation reliabilityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent removes the containment structure (bank) from the system entirely. Instead of using physical barriers to prevent ink spreading, the invention relies on self-aligned patterning through sequential deposition and photolithographic etching, where the pattern is defined by the mask and etching process rather than by containment walls.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the mechanical containment structure (physical banks) with a photolithographic patterning system. The pattern is defined by optical exposure through a photomask followed by chemical etching, substituting mechanical constraints with photochemical processing.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Manufacturing precision

If containment structures are used to prevent ink spreading, then manufacturing precision is improved, but fabrication speed decreases

Engineering Contradiction:

Improvelayer thickness uniformityVSAvoidfabrication speed

Core Design Contradiction:

Manufacturing precisionVSProductivity

Solution Approach 1:

The patent enables continuous processing by eliminating the need for complex containment structure fabrication. The perovskite layer is deposited continuously, followed by photomask application and photolithographic etching, allowing streamlined production without the need to manufacture and assemble physical containment structures.

Inventive Principle:

Principle #20Continuity of useful action

Solution Approach 2:

The patent replaces the mechanical containment structure (physical banks) with a photolithographic patterning system. The pattern is defined by optical exposure through a photomask followed by chemical etching, substituting mechanical constraints with photochemical processing.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 approach enables the creation of high-resolution, full-color displays with uniform film thickness and precise patterns, improving the efficiency and cost-effectiveness of the fabrication process while maintaining the crystalline structure and emission wavelength tunability of metal halide perovskites.

Implementation Method 1

forming a first pattern comprising metal second halide perovskite in the layer of metal first halide perovskite, and forming a second pattern comprising metal third halide perovskite in the layer of metal first halide perovskite

Methodology Applied

Scientific EffectHalide exchange: Chemical Bonding

Data Source

PatentUS11404658B2Light emitting layer, manufacturing method thereof, and display apparatus

Publication Date: 2022.08.02 BOE TECHNOLOGY GROUP CO LTD

AI summary

The present disclosure is related to a method of manufacturing a light-emitting layer. The method of manufacturing a light-emitting layer may include forming a layer of metal first halide perovskite on a substrate, forming a first pattern comprising metal second halide perovskite in the layer of metal first halide perovskite, and forming a second pattern comprising metal third halide perovskite in the layer of metal first halide perovskite.