Organic Semiconductor Patterning via Donor Substrate Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for patterning low-molecular weight organic semiconductors, such as pentacene, face challenges including high costs, difficulty in handling shadow masks, and limitations in producing high-definition, large-screen displays due to sagging masks and low luminous efficiency in organic light-emitting diodes.
Innovation Solution
A donor substrate with a base substrate and a transfer layer containing an organic semiconductor precursor with a thermally decomposable substituent is used, allowing for the formation of an organic semiconductor layer pattern through a wet process without deposition, using energy sources like heat or light to transfer the precursor to a receptor substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If shadow mask method is used for patterning low-molecular weight organic semiconductor, then deposition can be performed without lithography process, but shadow mask becomes expensive and cannot be unlimitedly used due to close positioning to substrate
Solution Approach 1:
The patent uses a shadow mask pattern as a template to create a photomask, which is then used for photolithography to form the organic semiconductor pattern. This copying approach eliminates the need for direct shadow mask deposition, allowing unlimited reuse of the photomask while maintaining pattern fidelity.
Solution Approach 2:
The patent introduces a photomask as an intermediary between the shadow mask pattern and the organic semiconductor layer. The photomask serves as a durable intermediate template that can be reused indefinitely, replacing the consumable shadow mask while preserving the intended pattern geometry.
2Manufacturing precision
If shadow mask is disposed very close to substrate to form fine pattern, then fine pattern can be achieved, but shadow mask is expensive and cannot be unlimitedly used
Solution Approach 1:
The shadow mask pattern is copied onto a photomask through photolithography, creating a reusable template that maintains the fine pattern geometry. This allows the pattern design to be preserved without the physical constraints and costs of repeated shadow mask fabrication.
Solution Approach 2:
The patent replaces the mechanical shadow mask deposition system with a photolithography system using light and photomasks. This substitution eliminates the mechanical constraints of shadow mask positioning and reuse, allowing unlimited use of the photomask while maintaining fine pattern resolution.
3Temperature
If radiation heat from heating device is applied to deposited material, then material can be heated for processing, but shadow mask sags due to thermal expansion
Solution Approach 1:
The pattern geometry is copied to a photomask before the heating step, so subsequent thermal processing does not affect shadow mask shape. The photomask serves as a stable template that can withstand the heating process without deforming.
Solution Approach 2:
The photomask acts as an intermediary that separates the pattern definition step from the thermal processing step. This allows the pattern to be established before heating, eliminating the thermal expansion problem that would otherwise distort the shadow mask during heating.
4Area of stationary object
If shadow mask is used for large substrate, then large area can be covered, but sagging of center portion becomes more serious blocking high-definition display manufacture
Solution Approach 1:
The shadow mask pattern is copied to a photomask that can be manufactured with precise dimensions suitable for large substrates. This copying process allows the pattern design to be scaled to large areas without the mechanical sagging problems of physical shadow masks.
Solution Approach 2:
The patent replaces the mechanical shadow mask system with a photolithography system using photomasks. This substitution eliminates the gravitational sagging issue that plagues large-area shadow masks, enabling high-definition patterning across large substrate areas.
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 enables the cost-effective production of high-definition, large-screen displays with improved luminous efficiency and flexibility, overcoming the limitations of traditional shadow mask techniques and deposition processes.
Implementation Method 1
a transfer layer containing an organic semiconductor precursor having a thermally decomposable substituent
Implementation Method 2
applying an energy source to the donor substrate to transfer the transfer layer to the receptor substrate
Data Source
AI summary
A donor substrate and a method of forming an organic semiconductor layer pattern using the donor substrate, whereby a donor substrate is formed using an organic semiconductor precursor having a thermally decomposable substituent through a wet process, the organic semiconductor precursor substrate in the donor substrate is transferred to a receptor substrate as a pattern and heated, and thus is changed into an organic semiconductor. As a result, an organic semiconductor layer pattern is obtained. The method can be used in the manufacture of various devices such as organic light emitting diode and organic thin film transistor. A low-molecular weight organic semiconductor layer pattern can be formed through a wet process, not through deposition. Thus, using the method, a flat display device can be conveniently manufactured at low cost.