UV-Release Adhesive Laminate for Large-Area Graphene Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The transfer of large-area graphene is technically challenging due to its thin film nature, leading to decreased transfer rates and potential damage during the transfer process, which affects productivity and quality.
Innovation Solution
A method involving a laminate structure where a two-dimensional material, such as graphene, is bonded to an adhesive sheet with an adhesive layer that decreases its adhesive force upon exposure to ultraviolet rays or heat, allowing for efficient transfer to a second substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a two-dimensional material is transferred from a catalytic metal to a substrate by etching the metal, then the two-dimensional material can be transferred to the substrate, but the transfer rate decreases as the area is increased and the material may be broken or damaged
Solution Approach 1:
The patent introduces a transfer sheet as an intermediary carrier between the catalytic metal and the final substrate. The two-dimensional material is first transferred to the transfer sheet, then subsequently transferred to the target substrate. This intermediary approach enables better control over the transfer process, maintaining high transfer rates while preserving material integrity, especially for large-area transfers.
Solution Approach 2:
The patent applies preliminary actions by first forming the two-dimensional material on the catalytic metal, then transferring it to the transfer sheet before final substrate placement. The adhesive layer is prepared in advance with specific adhesive force characteristics that allow controlled bonding and subsequent release. This preliminary preparation enables high transfer rates while maintaining material quality.
2Manufacturing precision
If the catalytic metal is removed by etching during transfer, then the two-dimensional material can be transferred, but the metal is lost and etching waste liquid requires treatment, reducing productivity
Solution Approach 1:
The transfer sheet serves as a mediator that captures the two-dimensional material from the catalytic metal through adhesive bonding. This allows the material to be separated from the metal substrate without requiring aggressive etching processes, thereby maintaining production efficiency while achieving complete transfer.
Solution Approach 2:
The patent replaces the chemical etching process with a mechanical/adhesive-based transfer mechanism. Instead of using chemicals to remove the metal and release the material, the adhesive layer mechanically bonds to the two-dimensional material and lifts it off the catalytic metal surface. This substitution eliminates waste liquid treatment requirements and improves productivity.
3Reliability
If a PET film is used for temporary fixing, then adhesion can be controlled, but it is difficult to transfer graphene to another substrate after etching
Solution Approach 1:
The patent employs an adhesive layer with temperature-dependent adhesive force characteristics. At room temperature, the adhesive force is high enough to securely bond the two-dimensional material to the transfer sheet. When heated to the detachment temperature, the adhesive force decreases, enabling easy release and transfer to the target substrate. This parameter change allows both reliable temporary fixing and efficient subsequent transfer.
Solution Approach 2:
The adhesive layer's adhesive force is made dynamic rather than static. It automatically adjusts its bonding strength based on temperature conditions: strong bonding at low temperature for secure attachment, and weak bonding at high temperature for easy release. This dynamic behavior enables both reliable temporary fixing and efficient transfer to other substrates without the limitations of conventional PET films.
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 high productivity and efficient transfer of two-dimensional materials at a high transfer rate, minimizing damage and ensuring quality, by utilizing a laminate structure with a specific adhesive layer that reduces adhesive force upon activation.
Implementation Method 1
an adhesive layer whose adhesive force decreases due to ultraviolet rays or heat
Implementation Method 2
an adhesive layer whose adhesive force decreases due to ultraviolet rays or heat
Data Source
AI summary
The present invention relates to a laminate including a two-dimensional material and an adhesive sheet having a base material and an adhesive layer whose adhesive force decreases due to ultraviolet rays or heat, in which an adhesive force A at 25° C. of the adhesive layer before the ultraviolet rays or heat applies, to a silicon wafer is 1.0 N/20 mm to 20.0 N/20 mm when the adhesive layer is subjected to 180° peeling at a tensile speed of 300 mm/min, and a surface roughness of an adhesive surface of the adhesive layer after the ultraviolet rays or heat has been applied is 0.01 μm to 8.00 μm.