Anisotropic Conductive Film Thickness Control for IC Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In organic EL display devices with flexible substrates, the resin composition containing electrically conductive material used for connecting electrode arrays and terminal arrays often remains hardened, leading to unstable electrical connections.
Innovation Solution
The implementation of an anisotropic conductive film with a thinner thickness over a second organic layer, which is positioned between the first organic layer covering the electrode arrays' peripheral edges and the IC, reduces residue and ensures a stable electrical connection by varying the film's thickness in different areas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a resin composition containing electrically conductive material is used to connect the driver IC and the substrate, then electrical connection between terminal arrays and electrode arrays is achieved, but the resin composition remains hardened in the area between organic films, leading to unstable electrical connection
Solution Approach 1:
The patent applies local quality by providing a second organic layer selectively in the area between the first organic films, where resin composition residue is problematic. This creates different local environments: areas with second organic layer have reduced resin residue, while other areas maintain the original structure. The second organic layer is specifically positioned to address the harmful effect of resin residue without modifying the entire structure.
2Reliability
If the electrically conductive film has uniform thickness, then manufacturing is simplified, but residue of the conductive film remains in areas between organic films, compromising connection stability
Solution Approach 1:
The patent implements local quality by creating a non-uniform thickness profile for the electrically conductive film. The film is thinner in the area above the second organic layer compared to areas above the first organic films. This localized thickness variation reduces resin composition residue in critical areas while maintaining adequate thickness elsewhere for reliable electrical connection, balancing manufacturing feasibility with connection stability.
3Reliability
If the electrically conductive film has larger thickness above the second organic layer, then electrical connection is improved, but residue of the conductive film increases, leading to unstable connection
Solution Approach 1:
The patent applies local quality by inverting the expected thickness distribution. Instead of making the conductive film uniformly thick or thicker above the second organic layer, the invention makes it thinner above the second organic layer and maintains adequate thickness above the first organic films. This localized thinning reduces harmful residue in the critical area between organic films while preserving electrical connection functionality through the first organic films' coverage areas.
Data Source
AI summary
A display device according to an embodiment of the present invention includes: on a substrate: an IC having a first and a second terminal array; a wiring layer having a first and a second electrode array, and a first organic layer having a covering part covering at least a part of a peripheral edge part of each of the first and the second electrode array; an electrically conductive film electrically connecting the first terminal array and the first electrode array, and the second terminal array and the second electrode array; a second organic layer provided in at least a part of an area between the covering part of the first electrode array and the covering part of the second electrode array, the electrically conductive film has a smaller thickness at a position above the second organic layer than at a position of the covering part of the first organic layer.