Touch Panel Conductive Frame and Electrode Manufacturing

Solution Overview

Problem

Capacitive type touch panels face reduced position recognition accuracy due to variations in film thickness and resistance values of the touch electrode caused by dry etching during the manufacturing process, especially with increasing substrate sizes.

Innovation Solution

A conductive portion is provided between the insulating substrate and the transparent touch electrode, allowing the touch electrode to be formed after the conductive portion, thus avoiding etching and reducing film thickness variations, and using alloy films like silver-palladium for the frame and wiring portions to enhance conductivity and reliability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the frame portion and wiring portions are formed by dry etching after the touch electrode is formed, then the conductive structure can be created, but the touch electrode surface is partially etched causing film thickness variation and resistance value variation

Engineering Contradiction:

Improveconductivity of frame and wiring portionsVSAvoidfilm thickness uniformity of touch electrode

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The frame portion and wiring portions are formed by dry etching before the touch electrode is formed. This preliminary action ensures that the conductive structure is created first, eliminating the risk of subsequent etching damage to the touch electrode. The touch electrode is then deposited over the pre-formed conductive structures, guaranteeing both conductivity and film thickness uniformity.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The conventional manufacturing sequence is inverted: instead of forming the touch electrode first and then the frame/wiring portions (which causes etching damage), the frame/wiring portions are formed first followed by the touch electrode. This inversion of the process sequence resolves the technical contradiction by preventing the harmful etching effect while maintaining all functional requirements.

Inventive Principle:

Principle #13The other way round (Inversion)

2Ease of manufacture

If the touch electrode is formed before the frame portion by dry etching, then the manufacturing process can proceed, but position recognition accuracy is reduced due to resistance value variation

Engineering Contradiction:

Improvemanufacturing process feasibilityVSAvoidposition recognition accuracy

Core Design Contradiction:

Ease of manufactureVSMeasurement precision

Solution Approach 1:

The frame portion and wiring portions are formed by dry etching before the touch electrode is formed. This preliminary action ensures that the conductive structure is created first, eliminating the risk of subsequent etching damage to the touch electrode. The touch electrode is then deposited over the pre-formed conductive structures, guaranteeing both conductivity and film thickness uniformity.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The conventional manufacturing sequence is inverted: instead of forming the touch electrode first and then the frame/wiring portions (which causes etching damage), the frame/wiring portions are formed first followed by the touch electrode. This inversion of the process sequence resolves the technical contradiction by preventing the harmful etching effect while maintaining all functional requirements.

Inventive Principle:

Principle #13The other way round (Inversion)

Data Source

PatentUS8243032B2Touch panel, display device and touch panel manufacturing method

Publication Date: 2012.08.14 GLOBAL OLED TECHNOLOGY LLC

AI summary

A touch panel includes an insulating substrate, a transparent touch electrode provided on the insulating substrate, and a frame portion connected to a periphery of the touch electrode. The touch panel detects a touched position on the touch electrode based on an electric signal through the frame portion. The frame portion is provided between the insulating substrate and the touch electrode.