Detachable Flex-to-Flex Electrical Connection for Flexible Substrates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mounting connectors on flexible substrates for printed flexible hybrid electronic circuits is challenging due to low temperature requirements, and existing solutions like anisotropic conductive adhesive films create permanent connections, while zero insertion force connectors are too rigid and bulky for small form factor applications, making detachable and re-attachable connections difficult.
Innovation Solution
A detachable electrical connection assembly using a conductive material and an adhesive composition that allows non-permanent attachment, detachment, and re-attachment, with the conductive material positioned between adhesive material on flexible substrates, enabling flexible interconnections between substrates, including disposable sensors, and using conductive ink drops and non-conductive adhesive material for selective attachment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If anisotropic conductive adhesive film is used to bond flexible circuits, then electrical connection is established, but the connection becomes permanent and non-detachable
Solution Approach 1:
The adhesive film is segmented into alternating conductive regions and non-conductive adhesive regions. The conductive regions provide electrical connection while the non-conductive adhesive regions provide detachable mechanical bonding, allowing the connection to be both electrically functional and mechanically reversible.
Solution Approach 2:
Different regions of the adhesive film have different local properties: conductive regions with conductive material for electrical connection, and non-conductive adhesive regions with adhesive material for mechanical attachment and detachment. This local differentiation resolves the contradiction between permanent electrical connection and reversible mechanical bonding.
2Adaptability or versatility
If zero insertion force connector is used for detachable connection, then detachability is achieved, but the fixture becomes rigid and bulky
Solution Approach 1:
The invention extracts the essential function of detachability from the complex ZIF connector mechanism and implements it through a simple adhesive film that can be applied directly to flexible substrates. This eliminates the need for bulky mechanical fixtures while maintaining detachability.
Solution Approach 2:
The invention uses a thin film structure with alternating conductive and adhesive regions that can be applied to flexible substrates. This thin film approach maintains flexibility and small form factor while providing detachable electrical connections, contrasting with rigid ZIF connectors.
3Reliability
If conventional bonding methods are used on flexible substrates, then connection is achieved, but temperature requirements are too high for flexible substrates
Solution Approach 1:
The invention changes the bonding parameter from high-temperature curing (conventional methods) to low-temperature pressure-sensitive adhesive bonding. This allows flexible substrates to be bonded without exposing them to temperatures that could damage the flexible material or onboard electronics.
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
Enables flexible, detachable, and re-attachable connections between substrates at low temperatures, allowing for easy replacement and repair of components without damaging the substrates, suitable for small form factor applications and flexible electronic circuits.
Implementation Method 1
an adhesive material consisting of an adhesive composition configured to permit non-permanent attachment, detachment and re-attachment to the adhesive
Implementation Method 2
a conductive material; and an adhesive material consisting of an adhesive composition configured to permit non-permanent attachment, detachment and re-attachment to the adhesive, wherein at least a portion of the conductive material is positioned between the adhesive material
Data Source
AI summary
Printed flexible hybrid electronic systems may require electrical interconnection to peripheral elements. For example, a printed sensor tag with wireless communication may need to connect to a printed sensing electrode on a separated substrate. Frequently, it is desired that these interconnections be detachable in order to replace peripheral elements or to facilitate low cost and simplified assembly, test, rework, and repair. Unlike conventional printed circuit board, mounting a connector on a flexible substrate for detachable connection is challenging due to low temperature requirements. Provide is a teaching of a thin film or form of electrical connection for two circuit elements on separate flexible substrates. The connection is detachable and re-attachable for replacing different circuit elements. The detachable connection is in embodiments realized by selective deposition of fine patterns of conductive materials and non-conductive repositionable pressure-sensitive adhesive.