Touch Substrate Merging Bridge and Wiring Photoetching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current touch substrates for Multi-Layer On-Cell (MLOC) structures in touch displays have complex manufacturing processes, leading to increased costs, reduced yield, and potential corrosion issues due to the use of multiple photoetching processes and metal etching solutions, which complicates the integration of electrode connecting bridges, signal wiring, and touch electrodes.
Innovation Solution
A touch substrate design featuring electrode connecting bridges, signal wiring layers, insulating layers, and touch electrodes arranged in a specific overlapping pattern, with ITO materials and simplified manufacturing steps that reduce the number of photoetching processes and prevent corrosion, using binding pins with integrated structures and passivation layers for improved stability and conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If multiple photoetching processes and metal etching solutions are used to form electrode connecting bridges and signal wiring, then the touch substrate can be manufactured with complex structures, but the manufacturing process becomes more complex, costs increase, and corrosion issues occur
Solution Approach 1:
The patent combines the formation of electrode connecting bridges and signal wiring into a single photoetching process. The insulating layer is patterned to expose both the electrode connecting bridge areas and signal wiring areas simultaneously, allowing both structures to be formed in one etching step using the same photoresist and etching solution, thereby simplifying the manufacturing process while maintaining complex structures
Solution Approach 2:
The insulating layer serves multiple functions: it provides electrical insulation between different components, defines the patterns for both electrode connecting bridges and signal wiring through its openings, and protects underlying layers during the single photoetching process. This multi-functionality reduces the number of separate processes needed
2Manufacturing precision
If multiple photoetching processes are used to form different layers and structures, then detailed patterns can be achieved, but manufacturing yield decreases and production time increases
Solution Approach 1:
By merging the patterning of electrode connecting bridges and signal wiring into a single photoetching process, the patent reduces the total number of process steps. This decreases the cumulative impact of process variations and contamination between steps, thereby improving manufacturing yield while maintaining the required pattern precision through proper mask design
3Reliability
If metal etching solutions are used to form electrode connecting bridges, then conductive structures can be created, but corrosion of touch electrodes occurs
Solution Approach 1:
The patent extracts the metal etching step from the process sequence by using a single photoetching process that forms all conductive structures (electrode connecting bridges and signal wiring) simultaneously. This eliminates the need for separate metal etching solutions that would otherwise corrode the touch electrodes, while still achieving the required conductive structures through the photoetching of the insulating layer
Solution Approach 2:
The patent converts the potential harm of needing separate etching steps into a benefit by using a single photoetching process that avoids corrosion issues. The same photoresist and etching solution used for patterning the insulating layer simultaneously define both the electrode connecting bridges and signal wiring, eliminating the harmful effect of metal etching solutions on touch electrodes
4Shape
If ITO materials are used for electrode connecting bridges, then visibility is improved (invisible bridges), but manufacturing complexity increases due to additional processes
Solution Approach 1:
The patent merges the formation of ITO electrode connecting bridges with the single photoetching process used for signal wiring. The ITO layer is deposited over the patterned insulating layer, and the same photoresist pattern defines both the insulating layer openings and the ITO bridge structures, allowing simultaneous formation in one process step without adding manufacturing complexity
Data Source
AI summary
A touch substrate and a method of forming the same, and a touch display device are provided. The touch substrate includes: electrode connecting bridges, a signal wiring layer, an insulating layer and a touch electrode layer which are sequentially formed along a direction away from a base, where the touch electrode layer includes a plurality of first touch electrodes and a plurality of second touch electrodes, and the first touch electrodes and the second touch electrodes are arranged in a crossed manner.