Flexible Circuit Conformal Coating Thickness Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for manufacturing flexible electronic circuits struggle to consistently and reliably expose sensor chips to the environment while maintaining precise control over the thickness of conformal material coatings, often resulting in excessive coating thickness and potential chip damage.
Innovation Solution
The methods involve forming positive photoresist molds on the flexible substrate, applying conformal material coatings, and using a controlled blade to remove excess coating, followed by oxygen plasma treatment and insertion of anisotropic conductive paste into cavities, allowing for precise control over coating thickness and selective chip exposure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conformal material coating is applied to protect chips, then mechanical and moisture ingress protection is improved, but coating thickness becomes excessive and overall circuit thickness increases
Solution Approach 1:
Positive photoresist molds are formed on the flexible substrate before applying the conformal material coating. These molds create cavities that define the exact thickness and shape of the coating, ensuring precise thickness control while maintaining protective functionality. The molds are removed after coating, leaving the precisely controlled conformal layer.
2Adaptability or versatility
If conformal material coating is removed from sensor chip or chip is masked during coating, then sensor chip exposure to external environment is achieved, but chip damage occurs or process complexity increases
Solution Approach 1:
The positive photoresist molds are applied selectively to specific regions of the flexible substrate where coating is desired. Areas with sensor chips that need exposure remain without molds, allowing the conformal material to be naturally excluded from those regions. This selective application achieves sensor exposure without requiring post-coating removal or masking operations.
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
These methods enable precise control over the thickness of conformal material coatings and allow for the selective exposure of sensor chips, preventing damage and enabling the production of smaller, thinner flexible electronic circuits.
Implementation Method 1
oxygen plasma treatment
Data Source
Figure 1~2B
Figure 3
Figure 4~6
AI summary
A method of manufacturing a flexible electronic circuit is provided. The method may include forming a positive photoresist mold on a flexible polymer substrate having a plurality of metal traces. The method may also include applying a conformal material coating over the positive photoresist mold, the flexible polymer substrate, and the metal traces. The method may further include removing an excess of the conformal material coating by running a blade over the positive photoresist mold. The method may also include removing the positive photoresist mold to reveal a cavity defined by the conformal material coating. The method may further include dispensing an anisotropic conductive paste into the cavity and inserting a chip into the cavity and bonding the chip to the metal traces.